/* =========================================================
   StudyPipe · Shared lesson components (used by every lesson)
   Builds on style.css tokens.
   ========================================================= */

body.lesson-page {
  background: var(--paper);
  padding-bottom: 110px;
}

:target, .l-sec, .section, [id] {
  scroll-margin-top: 76px;
  scroll-margin-bottom: 96px;
}

/* ---------- Top bar ---------- */
.l-nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: var(--ink-950);
  background: rgba(var(--ink-950-rgb), 0.95);
  -webkit-backdrop-filter: blur(20px) saturate(160%);
  backdrop-filter: blur(20px) saturate(160%);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.4);
}
.l-nav .nav-inner { height: 56px; }
.l-back { display: inline-flex; align-items: center; gap: 8px; text-decoration: none; color: var(--fg-soft); font-weight: 700; font-size: 14px; padding: 8px 12px; border-radius: 999px; }
.l-back:hover { background: rgba(255, 255, 255, .06); color: var(--fg); }
.l-crumb { font-family: var(--font-mono); font-size: 11.5px; letter-spacing: .12em; text-transform: uppercase; color: var(--muted); }
.l-crumb b { color: var(--amber); font-weight: 500; }

/* ---------- Hero ---------- */
.l-hero { position: relative; overflow: hidden; padding: 100px 0 64px; background: var(--ink-950); color: var(--fg); isolation: isolate; }
.l-hero::before {
  content: ""; position: absolute; inset: 0; z-index: -1;
  background: radial-gradient(50% 60% at 80% 40%, rgba(var(--crimson-rgb), .28), transparent 70%), radial-gradient(40% 50% at 10% 90%, rgba(var(--teal-rgb), .1), transparent 70%);
}
.l-hero-grid { display: grid; grid-template-columns: 1.15fr .85fr; gap: clamp(28px, 5vw, 72px); align-items: center; }
.l-hero h1 { font-size: clamp(2.8rem, 6.4vw, 5.4rem); margin-top: 18px; }
.l-hero .question { margin: 22px 0 0; font-family: var(--font-display); font-style: italic; font-size: clamp(1.3rem, 2.4vw, 1.8rem); color: var(--pink-soft); font-variation-settings: "opsz" 72, "SOFT" 100; }
.l-meta { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 28px; }
.chip {
  display: inline-flex; align-items: center; gap: 8px; padding: 7px 13px; border-radius: 999px; font-size: 13px; font-weight: 700;
  background: rgba(255, 255, 255, .06); box-shadow: inset 0 0 0 1px var(--line-strong); color: var(--fg-soft); white-space: nowrap;
}
.chip i { width: 7px; height: 7px; border-radius: 50%; background: var(--c, var(--amber)); }
.l-hero .hero-cta { margin-top: 34px; }

.cups-art { position: relative; display: flex; justify-content: center; align-items: flex-end; gap: clamp(10px, 2vw, 20px); padding: 40px 0 10px; }
.cups-art .cup { width: clamp(58px, 7vw, 84px); height: clamp(90px, 11vw, 128px); position: relative; border-radius: 6px 6px 18px 18px; background: rgba(255, 255, 255, .07); box-shadow: inset 0 0 0 2px rgba(255, 255, 255, .25); overflow: hidden; animation: cup-bob 5s ease-in-out infinite; animation-delay: var(--dl, 0s); }
.cups-art .cup::before { content: ""; position: absolute; left: 0; right: 0; bottom: 0; height: 62%; background: var(--liq); box-shadow: inset 0 10px 18px rgba(255, 255, 255, .15); border-radius: 0 0 16px 16px; }
.cups-art .cup::after { content: ""; position: absolute; top: 6px; bottom: 10px; left: 8px; width: 6px; border-radius: calc(4px * var(--corner, 1)); background: rgba(255, 255, 255, .25); }
.cups-art .cup span { position: absolute; bottom: -28px; left: 50%; transform: translateX(-50%); font-family: var(--font-mono); font-size: 10.5px; color: var(--muted); white-space: nowrap; }
.cups-art .halo { position: absolute; inset: 10% 0 0; background: radial-gradient(circle at 50% 70%, rgba(var(--pink-rgb), .3), transparent 60%); filter: blur(10px); z-index: -1; }
@keyframes cup-bob { 50% { transform: translateY(-6px); } }

/* ---------- Layout with progress rail ---------- */
.l-layout { display: grid; grid-template-columns: 220px minmax(0, 1fr); gap: clamp(24px, 4vw, 56px); max-width: 1320px; margin: 0 auto; padding: 0 var(--gutter); }
.l-rail { position: sticky; top: 88px; align-self: start; padding: 40px 0; }
.l-rail ol { list-style: none; margin: 0; padding: 0; display: grid; gap: 2px; counter-reset: rail; }
.l-rail a {
  counter-increment: rail; display: grid; grid-template-columns: 26px 1fr; align-items: center; gap: 10px;
  padding: 9px 10px; border-radius: calc(12px * var(--corner, 1)); text-decoration: none; color: var(--paper-muted); font-weight: 700; font-size: 14px; transition: background .2s, color .2s;
}
.l-rail a::before {
  content: counter(rail); width: 26px; height: 26px; border-radius: 50%; display: grid; place-items: center; font-family: var(--font-mono); font-size: 11px;
  background: rgba(var(--paper-ink-rgb), .07); color: var(--paper-ink); transition: background .2s, color .2s;
}
.l-rail a:hover { background: rgba(var(--paper-ink-rgb), .05); color: var(--paper-ink); }
.l-rail a.active { background: var(--paper-ink); color: var(--paper); }
.l-rail a.active::before { background: var(--amber); color: var(--on-amber); }
.l-rail a.done::before { content: "✓"; background: var(--ok); color: #fff; }
.l-rail .rail-progress { margin-top: 18px; height: 6px; border-radius: calc(3px * var(--corner, 1)); background: rgba(var(--paper-ink-rgb), .08); overflow: hidden; }
.l-rail .rail-progress i { display: block; height: 100%; width: 0; background: linear-gradient(90deg, var(--pink), var(--amber)); transition: width .4s var(--ease); }
.l-rail small { display: block; margin-top: 8px; font-size: 12px; color: var(--paper-muted); }

.l-main { min-width: 0; color: var(--paper-ink); padding-bottom: 80px; }
.l-sec { padding: 80px 0 20px; scroll-margin-top: 80px; }
.l-sec + .l-sec { border-top: 1px solid var(--paper-line); }
.phase {
  display: inline-flex; align-items: center; gap: 10px; font-family: var(--font-mono); font-size: 12px; letter-spacing: .14em; text-transform: uppercase;
  color: var(--pc, var(--crimson));
}
.phase b { display: inline-grid; place-items: center; width: 26px; height: 26px; border-radius: 50%; background: var(--pc, var(--crimson)); color: #fff; font-weight: 500; letter-spacing: 0; }
.l-sec h2 { font-family: var(--font-display); font-weight: 600; font-size: clamp(2rem, 4vw, 3rem); line-height: 1.05; letter-spacing: -0.02em; margin: 14px 0 0; font-variation-settings: "opsz" 120, "SOFT" 30; }
.l-sec h2 em { font-style: italic; font-weight: 500; color: var(--crimson); }
.l-sec h3 { font-family: var(--font-display); font-weight: 600; font-size: 1.55rem; line-height: 1.15; margin: 44px 0 0; font-variation-settings: "opsz" 48, "SOFT" 40; }
.l-sec h4 { font-size: 1.02rem; font-weight: 800; margin: 26px 0 0; }
.l-sec p, .l-sec li { font-size: 17px; line-height: 1.7; color: #3c372e; }
.l-sec p { margin: 14px 0 0; max-width: 72ch; }
.l-sec .intro { font-size: 1.15rem; color: var(--paper-muted); max-width: 64ch; }
.l-sec strong { color: var(--paper-ink); }
.l-sec ul.clean { padding-left: 20px; margin: 12px 0 0; }
.l-sec ul.clean li { margin: 6px 0; }

/* ---------- Cards & callouts ---------- */
.grid-2 { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 16px; margin-top: 24px; }
.grid-3 { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 16px; margin-top: 24px; }
.card { background: var(--paper-card); border: 1px solid var(--paper-line); border-radius: var(--radius); padding: 22px; }
.card h4 { margin-top: 0; }
.card p { font-size: 15.5px; margin-top: 8px; }
.callout { margin-top: 24px; border-radius: var(--radius); padding: 18px 20px 18px 56px; position: relative; background: var(--paper-card); border: 1px solid var(--paper-line); }
.callout::before { position: absolute; left: 18px; top: 17px; width: 26px; height: 26px; border-radius: calc(8px * var(--corner, 1)); display: grid; place-items: center; font-weight: 800; font-size: 14px; color: #fff; }
.callout p { margin: 4px 0 0; font-size: 15.5px; }
.callout p:first-child { margin-top: 0; }
.callout.safety { background: var(--bad-tint-2); border-color: rgba(var(--crimson-rgb), .3); }
.callout.safety::before { content: "!"; background: var(--crimson); }
.callout.tip::before { content: "✦"; background: var(--warn); }
.callout.info::before { content: "i"; background: var(--info); }
.callout.big { background: var(--paper-ink); border: 0; color: var(--paper); padding: 26px 28px 26px 70px; }
.callout.big::before { content: "★"; background: var(--amber); color: var(--on-amber); width: 34px; height: 34px; left: 22px; top: 24px; }
.callout.big p { color: var(--on-ink-soft); font-size: 17px; }
.callout.big strong { color: var(--amber); }
.callout h4 { margin: 0; }

.objectives { list-style: none; padding: 0; margin: 22px 0 0; display: grid; gap: 10px; }
.objectives li { display: grid; grid-template-columns: 34px 1fr; gap: 12px; align-items: start; background: rgba(255, 255, 255, .04); border: 1px solid var(--line); border-radius: calc(14px * var(--corner, 1)); padding: 12px 14px; font-size: 15.5px; color: var(--fg-soft); line-height: 1.5; }
.objectives li b { display: grid; place-items: center; width: 34px; height: 34px; border-radius: calc(10px * var(--corner, 1)); background: rgba(var(--amber-rgb), .12); color: var(--amber); font-family: var(--font-mono); font-weight: 500; font-size: 13px; }

/* ---------- Story / case ---------- */
.story { margin-top: 26px; display: grid; grid-template-columns: 1fr 300px; gap: 24px; align-items: stretch; }
.story-text { background: var(--paper-card); border-radius: var(--radius-lg); padding: clamp(22px, 3vw, 34px); border: 1px solid var(--paper-line); position: relative; }
.story-text::before { content: "“"; position: absolute; top: -18px; left: 22px; font-family: var(--font-display); font-size: 90px; line-height: 1; color: var(--crimson); }
.story-text p { font-family: var(--font-display); font-size: 1.22rem; line-height: 1.55; color: var(--paper-ink); font-variation-settings: "opsz" 24, "SOFT" 50; }
.story-file { background: var(--paper-ink); color: var(--paper); border-radius: var(--radius-lg); padding: 24px; font-family: var(--font-mono); font-size: 13px; line-height: 1.8; }
.story-file h5 { margin: 0 0 12px; font-size: 11px; letter-spacing: .14em; color: var(--amber); font-weight: 500; }
.story-file dl { margin: 0; display: grid; grid-template-columns: auto 1fr; gap: 4px 12px; }
.story-file dt { color: var(--paper-faint); }
.story-file dd { margin: 0; }

/* ---------- Wonder wall ---------- */
.wall-form { display: flex; gap: 10px; margin-top: 18px; flex-wrap: wrap; }
.wall-form input, .l-input, .l-textarea {
  flex: 1; min-width: 220px; font: inherit; font-size: 16px; padding: 14px 16px; border-radius: calc(14px * var(--corner, 1)); border: 1.5px solid rgba(var(--paper-ink-rgb), .18); background: #fffdf8; color: var(--paper-ink);
}
.l-textarea { width: 100%; min-height: 96px; resize: vertical; display: block; margin-top: 12px; }
.wall-form input:focus, .l-input:focus, .l-textarea:focus { outline: none; border-color: var(--crimson); box-shadow: 0 0 0 4px rgba(var(--crimson-rgb), .12); }
.btn-ink { --bg: var(--paper-ink); --c: var(--paper); box-shadow: none; }
.btn-ink:hover { box-shadow: 0 12px 24px -12px rgba(var(--paper-ink-rgb), .6); }
.btn-soft { background: rgba(var(--paper-ink-rgb), .07); color: var(--paper-ink); box-shadow: none; }
.btn-soft:hover { background: rgba(var(--paper-ink-rgb), .12); box-shadow: none; }
.btn-sm { padding: 10px 16px; font-size: 14px; }
.wall { margin-top: 18px; display: flex; flex-wrap: wrap; gap: 14px; min-height: 40px; }
.note {
  width: 210px; min-height: 120px; padding: 16px 16px 30px; background: var(--nc, #ffe58a); color: #2a2311; font-family: var(--font-display); font-size: 1.05rem; line-height: 1.35;
  box-shadow: 0 12px 20px -12px rgba(60, 40, 10, .5); transform: rotate(var(--r, -1.5deg)); position: relative; animation: note-in .5s var(--ease);
  font-variation-settings: "opsz" 24, "SOFT" 100, "WONK" 1;
}
.note button { position: absolute; right: 6px; bottom: 4px; border: 0; background: none; cursor: pointer; font-size: 12px; color: rgba(42, 35, 17, .6); }
@keyframes note-in { from { opacity: 0; transform: scale(.8) rotate(-8deg); } }
.seed-qs { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 12px; }
.seed-qs button { border: 1px dashed rgba(var(--paper-ink-rgb), .3); background: transparent; border-radius: 999px; padding: 7px 12px; font-size: 13.5px; cursor: pointer; color: var(--paper-muted); }
.seed-qs button:hover { border-style: solid; color: var(--paper-ink); }

/* ---------- Sorting game ---------- */
.sort { margin-top: 26px; background: var(--ink-900); color: var(--fg); border-radius: var(--radius-lg); padding: clamp(18px, 3vw, 30px); }
.sort-tray { display: flex; flex-wrap: wrap; gap: 10px; min-height: 56px; padding: 6px; border-radius: calc(16px * var(--corner, 1)); }
.sort-item {
  display: inline-flex; align-items: center; gap: 10px; padding: 10px 14px; border-radius: calc(14px * var(--corner, 1)); cursor: grab; font-weight: 700; font-size: 14.5px;
  background: rgba(255, 255, 255, .07); border: 1px solid var(--line-strong); color: var(--fg); transition: transform .2s, background .2s, box-shadow .2s; touch-action: none;
  -webkit-user-select: none; user-select: none;
}
.sort-item .emo { width: 26px; height: 26px; border-radius: calc(8px * var(--corner, 1)); display: grid; place-items: center; background: var(--ic, rgba(255, 255, 255, .1)); font-size: 13px; }
.sort-item:hover { background: rgba(255, 255, 255, .12); }
.sort-item.picked { box-shadow: 0 0 0 2px var(--amber); background: rgba(var(--amber-rgb), .15); transform: translateY(-2px); }
.sort-item.right { box-shadow: 0 0 0 2px var(--teal); }
.sort-item.wrong { box-shadow: 0 0 0 2px var(--pink); animation: shake .4s; }
.sort-item.dragging { opacity: .4; }
@keyframes shake { 25% { transform: translateX(-4px); } 75% { transform: translateX(4px); } }
.bins { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 12px; margin-top: 18px; }
.bin { border-radius: calc(18px * var(--corner, 1)); padding: 14px; min-height: 170px; border: 2px dashed rgba(255, 255, 255, .16); transition: border-color .2s, background .2s; cursor: pointer; }
.bin h4 { margin: 0 0 4px; font-size: 15px; display: flex; align-items: center; gap: 8px; color: var(--fg); }
.bin h4 i { width: 12px; height: 12px; border-radius: 50%; background: var(--bc); }
.bin small { color: var(--muted); font-size: 12px; font-family: var(--font-mono); }
.bin .drop { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 12px; }
.bin.over, .bin.ready { border-color: var(--bc); background: color-mix(in srgb, var(--bc) 10%, transparent); }
.sort-bar { display: flex; flex-wrap: wrap; align-items: center; gap: 12px; margin-top: 18px; }
.sort-score { font-family: var(--font-mono); font-size: 14px; color: var(--fg-soft); }
.sort-feedback { margin-top: 16px; display: none; gap: 8px; }
.sort-feedback.on { display: grid; }
.fb-row { display: grid; grid-template-columns: 22px 170px 1fr; gap: 10px; font-size: 14px; color: var(--fg-soft); padding: 8px 10px; border-radius: calc(10px * var(--corner, 1)); background: rgba(255, 255, 255, .04); }
.fb-row b { color: var(--fg); }
.fb-row .ok { color: var(--teal); } .fb-row .no { color: var(--pink); }

/* ---------- Practical ---------- */
.prac-head { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 12px; margin-top: 24px; }
.prac-head .card { padding: 16px; }
.prac-head .card small { font-family: var(--font-mono); font-size: 11px; letter-spacing: .1em; color: var(--paper-muted); text-transform: uppercase; }
.prac-head .card b { display: block; margin-top: 4px; font-size: 15px; }
.materials { columns: 2; column-gap: 28px; margin: 14px 0 0; padding-left: 20px; }
.materials li { break-inside: avoid; font-size: 15.5px; margin: 4px 0; }
/* Methods & step cards */
.methods {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  margin-top: 18px;
}
@media (max-width: 640px) {
  .methods {
    grid-template-columns: 1fr;
  }
}
div.method {
  background: var(--paper-card);
  border: 1px solid var(--paper-line);
  border-radius: calc(14px * var(--corner, 1));
  padding: 16px;
  display: flex;
  flex-direction: column;
  gap: 6px;
  box-shadow: 0 4px 12px rgba(var(--paper-ink-rgb), 0.04);
  transition: transform 0.2s, border-color 0.2s;
}
div.method:hover {
  border-color: rgba(var(--crimson-rgb), 0.35);
  transform: translateY(-2px);
}
div.method b {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--crimson);
}
div.method h4 {
  margin: 0;
  font-size: 15px;
  color: var(--paper-ink);
}
div.method p {
  margin: 0;
  font-size: 13.5px;
  color: var(--paper-muted);
  line-height: 1.5;
}
ol.method { list-style: none; counter-reset: m; padding: 0; margin: 20px 0 0; display: grid; gap: 10px; }
ol.method li { counter-increment: m; display: grid; grid-template-columns: 40px 1fr; gap: 14px; background: var(--paper-card); border: 1px solid var(--paper-line); border-radius: calc(16px * var(--corner, 1)); padding: 14px 16px; font-size: 15.5px; line-height: 1.6; }
ol.method li::before { content: counter(m); width: 40px; height: 40px; border-radius: calc(12px * var(--corner, 1)); background: var(--paper-ink); color: var(--paper); display: grid; place-items: center; font-family: var(--font-display); font-weight: 600; font-size: 18px; }
ol.method li.now { border-color: var(--amber); box-shadow: 0 0 0 3px rgba(var(--amber-rgb), .25); }

/* 3D stages */
.stage { position: relative; margin-top: 26px; border-radius: var(--radius-lg); overflow: hidden; background: radial-gradient(70% 70% at 50% 30%, #1a2340, var(--ink-950)); color: var(--fg); box-shadow: 0 30px 60px -30px rgba(10, 10, 30, .6); }
.stage-canvas { position: relative; height: clamp(340px, 48vw, 480px); }
.stage-canvas canvas { position: absolute; inset: 0; width: 100% !important; height: 100% !important; touch-action: pan-y; }
.stage-label { position: absolute; top: 14px; left: 16px; z-index: 2; font-family: var(--font-mono); font-size: 11px; letter-spacing: .12em; text-transform: uppercase; color: var(--muted); display: flex; gap: 8px; align-items: center; }
.stage-label i { width: 6px; height: 6px; border-radius: 50%; background: var(--teal); box-shadow: 0 0 10px var(--teal); }
.stage-bar { display: flex; flex-wrap: wrap; align-items: center; gap: 10px; padding: 14px 16px; border-top: 1px solid var(--line); background: rgba(var(--ink-950-rgb), .75); }
.seg { display: inline-flex; padding: 4px; border-radius: calc(12px * var(--corner, 1)); background: rgba(255, 255, 255, .06); gap: 4px; flex-wrap: wrap; }
.seg button { border: 0; background: transparent; color: var(--fg-soft); padding: 8px 14px; border-radius: calc(9px * var(--corner, 1)); font-weight: 700; font-size: 13px; cursor: pointer; transition: all .2s; }
.seg button[aria-pressed="true"] { background: var(--fg); color: var(--ink-950); box-shadow: 0 2px 8px rgba(0,0,0,.4); }
.stage-hint { font-size: 13px; color: var(--muted); margin-left: auto; }
.stage-hint b { color: var(--fg); }
.stage-fallback { display: none; position: absolute; inset: 0; place-items: center; text-align: center; color: var(--muted); padding: 20px; }
.stage.no-webgl .stage-fallback { display: grid; }
.stage-toast { position: absolute; left: 50%; top: 16px; transform: translate(-50%, -10px); opacity: 0; transition: .4s var(--ease); background: var(--paper); color: var(--paper-ink); padding: 10px 16px; border-radius: calc(12px * var(--corner, 1)); font-size: 14px; font-weight: 700; z-index: 3; pointer-events: none; max-width: calc(100% - 24px); text-align: center; }
.stage-toast.show { opacity: 1; transform: translate(-50%, 0); }
.counters { display: flex; gap: 8px; flex-wrap: wrap; }
.counter { font-family: var(--font-mono); font-size: 12px; padding: 6px 11px; border-radius: calc(10px * var(--corner, 1)); background: rgba(255, 255, 255, .07); border: 1px solid rgba(255, 255, 255, .08); color: var(--fg-soft); }
.counter b { color: var(--fg); font-weight: 600; margin-left: 4px; }
.counter i { display: inline-block; width: 8px; height: 8px; border-radius: 50%; background: var(--c); margin-right: 6px; }
.range { display: flex; align-items: center; gap: 10px; font-size: 13.5px; color: var(--fg-soft); font-weight: 700; }
.range input { width: 160px; accent-color: var(--amber); }

/* ---------- Tables ---------- */
.tbl-wrap { overflow-x: auto; margin-top: 20px; border-radius: calc(16px * var(--corner, 1)); border: 1px solid var(--paper-line); background: var(--paper-card); }
.tbl { width: 100%; border-collapse: collapse; font-size: 15px; min-width: 560px; }
.tbl th, .tbl td { text-align: left; padding: 12px 14px; border-bottom: 1px solid var(--paper-line); vertical-align: middle; }
.tbl th { font-family: var(--font-mono); font-size: 11.5px; letter-spacing: .08em; text-transform: uppercase; color: var(--paper-muted); font-weight: 500; background: rgba(var(--paper-ink-rgb), .03); }
.tbl tr:last-child td { border-bottom: 0; }
.tbl select { font: inherit; font-size: 14px; padding: 8px 10px; border-radius: calc(10px * var(--corner, 1)); border: 1.5px solid rgba(var(--paper-ink-rgb), .18); background: #fff; color: var(--paper-ink); max-width: 100%; }
.tbl td.ok { background: rgba(var(--ok-rgb), .1); }
.tbl td.no { background: rgba(var(--crimson-rgb), .08); }
.sw { display: inline-block; width: 18px; height: 18px; border-radius: 50%; vertical-align: -4px; margin-right: 8px; box-shadow: inset 0 0 0 1px rgba(0, 0, 0, .15); }

/* ---------- Reveal / solutions ---------- */
details.reveal-box { margin-top: 16px; border-radius: calc(16px * var(--corner, 1)); border: 1px solid var(--paper-line); background: var(--paper-card); overflow: hidden; }
details.reveal-box > summary {
  list-style: none; cursor: pointer; padding: 14px 18px; font-weight: 800; font-size: 15px; display: flex; align-items: center; gap: 10px; color: var(--paper-ink);
}
details.reveal-box > summary::-webkit-details-marker { display: none; }
details.reveal-box > summary::before { content: "+"; width: 24px; height: 24px; border-radius: calc(8px * var(--corner, 1)); display: grid; place-items: center; background: var(--paper-ink); color: var(--paper); font-weight: 600; transition: transform .3s; }
details.reveal-box[open] > summary::before { content: "−"; }
details.reveal-box > summary small { margin-left: auto; font-weight: 600; color: var(--paper-muted); font-size: 12.5px; }
.reveal-body { padding: 0 18px 18px; border-top: 1px dashed var(--paper-line); }
.reveal-body p, .reveal-body li { font-size: 15.5px; }
details.solution > summary::before { background: var(--ok); }
details.solution[open] { border-color: rgba(var(--ok-rgb), .4); background: var(--ok-tint-2); }
details.locked > summary { opacity: .55; cursor: not-allowed; }

/* ---------- Equations ---------- */
.eq {
  font-family: var(--font-mono); font-size: clamp(14px, 1.6vw, 17px); background: var(--paper-ink); color: var(--paper); padding: 14px 18px; border-radius: calc(14px * var(--corner, 1)); margin-top: 14px;
  overflow-x: auto; white-space: nowrap; line-height: 1.6;
}
.eq .arr { color: var(--amber); padding: 0 6px; }
.eq .st { color: var(--paper-faint); font-size: .82em; }
.eq.light { background: var(--paper-card); color: var(--paper-ink); border: 1px solid var(--paper-line); }
.eq.light .st { color: var(--paper-muted); }
.eq-label { font-family: var(--font-mono); font-size: 11px; letter-spacing: .1em; text-transform: uppercase; color: var(--paper-muted); margin-top: 18px; display: block; }

/* ---------- pH explorer ---------- */
.ph-explorer { margin-top: 26px; background: var(--ink-900); border-radius: var(--radius-lg); padding: clamp(18px, 3vw, 30px); color: var(--fg); }
.ph-track { position: relative; height: 26px; margin-left: 10px; margin-right: 10px; border-radius: 999px; background: linear-gradient(90deg, #e3242b 0%, #f2562a 14%, #f99a2a 25%, #f7d52b 36%, #a9d53a 46%, #3fb04a 52%, #1b9a85 62%, #1c74b8 74%, #3a3fb0 86%, #5b2a8e 100%); margin-top: 70px; }
.ph-pin { position: absolute; top: 50%; width: 14px; height: 14px; margin: -7px 0 0 -7px; border-radius: 50%; background: #fff; box-shadow: 0 0 0 3px rgba(0, 0, 0, .3); cursor: pointer; border: 0; padding: 0; transition: transform .2s; }
.ph-pin:hover, .ph-pin.on { transform: scale(1.45); }
.ph-pin span { position: absolute; bottom: 20px; left: 50%; transform: translateX(-50%); white-space: nowrap; font-size: 18px; line-height: 1; pointer-events: none; transition: transform .2s; }
.ph-pin.up span { bottom: 44px; }
.ph-pin span::after { content: ""; position: absolute; left: 50%; top: 100%; width: 1px; height: 6px; background: rgba(255,255,255,.3); }
.ph-pin.up span::after { height: 30px; }
.ph-nums { position: relative; height: 18px; margin-top: 8px; font-family: var(--font-mono); font-size: 11px; color: var(--muted); }
.ph-nums span { position: absolute; transform: translateX(-50%); }
.ph-zones { display: grid; grid-template-columns: 7fr 0.6fr 7fr; gap: 6px; margin-top: 10px; font-size: 12px; font-family: var(--font-mono); text-align: center; color: var(--muted); }
.ph-zones div { padding: 6px; border-radius: calc(8px * var(--corner, 1)); background: rgba(255, 255, 255, .04); }
.ph-info { margin-top: 18px; min-height: 64px; padding: 14px 16px; border-radius: calc(14px * var(--corner, 1)); background: rgba(255, 255, 255, .05); font-size: 15px; color: var(--fg-soft); }
.ph-info b { color: var(--fg); }

/* ---------- Worked examples ---------- */
.example { margin-top: 26px; border-radius: var(--radius-lg); background: var(--paper-card); border: 1px solid var(--paper-line); overflow: hidden; }
.example-head { display: flex; align-items: center; gap: 14px; padding: 18px 22px; background: rgba(var(--paper-ink-rgb), .04); border-bottom: 1px solid var(--paper-line); }
.example-head .tag-ex { font-family: var(--font-mono); font-size: 11.5px; letter-spacing: .1em; padding: 5px 10px; border-radius: calc(8px * var(--corner, 1)); background: var(--crimson); color: #fff; }
.example-head h4 { margin: 0; font-size: 1.05rem; }
.example-body { padding: 4px 22px 22px; }
.example-body .q { font-size: 16px; font-weight: 600; color: var(--paper-ink); margin-top: 16px; }
.steps-sol { list-style: none; padding: 0; margin: 14px 0 0; counter-reset: s; display: grid; gap: 10px; }
.steps-sol li { counter-increment: s; position: relative; padding-left: 40px; font-size: 15.5px; line-height: 1.6; }
.steps-sol li::before { content: "Step " counter(s); position: absolute; left: 0; top: 2px; font-family: var(--font-mono); font-size: 10px; letter-spacing: .06em; color: var(--crimson); width: 34px; line-height: 1.2; }
.answer-line { margin-top: 14px; padding: 12px 16px; border-radius: calc(12px * var(--corner, 1)); background: rgba(var(--ok-rgb), .1); border-left: 4px solid var(--ok); font-weight: 700; font-size: 15.5px; }

/* ---------- Two-vinegar test ---------- */
.vt { margin-top: 26px; background: var(--ink-900); color: var(--fg); border-radius: var(--radius-lg); padding: clamp(18px, 3vw, 30px); }
.vt-cups { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; margin-top: 8px; }
.vt-cup { text-align: center; padding: 18px; border-radius: calc(20px * var(--corner, 1)); background: rgba(255, 255, 255, .04); border: 1px solid var(--line); }
.vt-glass { width: 120px; height: 150px; margin: 10px auto 0; position: relative; border-radius: 8px 8px 26px 26px; box-shadow: inset 0 0 0 2px rgba(255, 255, 255, .3); overflow: hidden; background: rgba(255, 255, 255, .04); }
.vt-glass .liq { position: absolute; left: 0; right: 0; bottom: 0; height: 55%; background: var(--vc, #f2e6c8); transition: background .6s, height .3s; border-radius: 0 0 24px 24px; }
.vt-glass .liq::after { content: ""; position: absolute; left: 8px; top: 8px; bottom: 8px; width: 6px; border-radius: calc(4px * var(--corner, 1)); background: rgba(255, 255, 255, .25); }
.vt-drop { position: absolute; left: 50%; top: -14px; width: 10px; height: 14px; margin-left: -5px; border-radius: 50% 50% 50% 50% / 60% 60% 40% 40%; background: #dff1ff; opacity: 0; }
.vt-drop.fall { animation: vt-fall .45s ease-in forwards; }
@keyframes vt-fall { 0% { opacity: 1; transform: translateY(0); } 100% { opacity: .2; transform: translateY(80px); } }
.vt-cup h4 { margin: 0; font-size: 16px; color: var(--fg); }
.vt-count { font-family: var(--font-mono); font-size: 28px; margin-top: 12px; color: var(--fg); }
.vt-count small { font-size: 12px; color: var(--muted); display: block; }
.vt-actions { display: flex; flex-wrap: wrap; gap: 8px; justify-content: center; margin-top: 12px; }
.vt-btn { border: 0; border-radius: calc(12px * var(--corner, 1)); padding: 10px 14px; font-weight: 700; font-size: 13.5px; cursor: pointer; background: rgba(255, 255, 255, .08); color: var(--fg); }
.vt-btn:hover { background: rgba(255, 255, 255, .14); }
.vt-btn.zobo { background: rgba(var(--crimson-rgb), .25); }
.vt-btn:disabled { opacity: .4; cursor: not-allowed; }
.vt .vt-status { margin-top: 10px; font-size: 14px; color: var(--fg-soft); min-height: 2.6em; max-width: none; text-align: center; }
.vt .vt-status strong { color: var(--fg); }
.stage .stage-fallback p { color: var(--muted); }
.vt-verdict { margin-top: 18px; padding: 16px 18px; border-radius: calc(14px * var(--corner, 1)); background: var(--paper); color: var(--paper-ink); display: none; font-size: 15.5px; }
.vt-verdict.on { display: block; animation: panel-in .5s var(--ease); }

/* ---------- Quiz ---------- */
.quiz { margin-top: 26px; display: grid; gap: 18px; }
.qcard { background: var(--paper-card); border: 1px solid var(--paper-line); border-radius: calc(18px * var(--corner, 1)); padding: 22px; box-shadow: 0 4px 16px rgba(var(--paper-ink-rgb), 0.05); }
.qcard .qn { font-family: var(--font-mono); font-size: 11.5px; letter-spacing: .1em; color: var(--paper-muted); text-transform: uppercase; }
.qcard .qt { margin: 8px 0 0; font-weight: 700; font-size: 16.5px; color: var(--paper-ink); line-height: 1.5; }
.qopts { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; margin-top: 16px; }
.qopt {
  text-align: left; border: 1.5px solid rgba(var(--paper-ink-rgb), .15); background: #fff; border-radius: calc(14px * var(--corner, 1)); padding: 12px 14px; cursor: pointer; font: inherit; font-size: 14.5px; color: var(--paper-ink);
  display: grid; grid-template-columns: 28px 1fr; gap: 10px; align-items: center; min-height: 48px; transition: border-color .2s, background .2s, box-shadow .2s;
}
.qopt b { width: 28px; height: 28px; border-radius: calc(8px * var(--corner, 1)); display: grid; place-items: center; background: rgba(var(--paper-ink-rgb), .07); font-family: var(--font-mono); font-size: 12px; font-weight: 700; }
.qopt:hover { border-color: var(--paper-ink); background: #faf7f2; }
.qopt.correct { border-color: var(--ok); background: var(--ok-tint); box-shadow: 0 0 0 2px rgba(var(--ok-rgb), 0.2); }
.qopt.correct b { background: var(--ok); color: #fff; }
.qopt.incorrect { border-color: var(--crimson); background: var(--bad-tint); box-shadow: 0 0 0 2px rgba(var(--crimson-rgb), 0.2); }
.qopt.incorrect b { background: var(--crimson); color: #fff; }
.qopt:disabled { cursor: default; }
.qexp { display: none; margin-top: 14px; padding: 14px 16px; border-radius: calc(12px * var(--corner, 1)); background: var(--ok-tint-2); border-left: 4px solid var(--ok); font-size: 14.5px; line-height: 1.6; color: #164e3c; }
.qexp.on { display: block; animation: panel-in .4s var(--ease); }
.quiz-score { display: flex; align-items: center; justify-content: space-between; gap: 12px; flex-wrap: wrap; padding: 16px 20px; border-radius: calc(18px * var(--corner, 1)); background: var(--paper-ink); color: var(--paper); margin-top: 20px; z-index: 5; box-shadow: 0 10px 30px rgba(0, 0, 0, 0.25); }
.quiz-score b { font-family: var(--font-display); font-size: 1.7rem; font-weight: 600; color: var(--amber); }

/* ---------- Do Now (retrieval starter) + blank-page recall ---------- */
.donow { margin-top: 26px; display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 14px; }
.dn-card { display: flex; flex-direction: column; align-items: flex-start; background: var(--paper-card); border: 1px solid var(--paper-line); border-radius: var(--radius); padding: 20px; transition: border-color .3s; }
.dn-card .qn { font-family: var(--font-mono); font-size: 11.5px; letter-spacing: .1em; color: var(--paper-muted); }
.dn-card .qt { margin: 6px 0 16px; font-weight: 700; font-size: 16.5px; color: var(--paper-ink); line-height: 1.5; }
.dn-reveal, .dn-ans { margin-top: auto; }
.dn-ans { width: 100%; animation: panel-in .4s var(--ease); }
.dn-a { padding: 12px 14px; border-radius: calc(12px * var(--corner, 1)); background: rgba(var(--paper-ink-rgb), .05); font-size: 15px; line-height: 1.6; }
.dn-mark { display: flex; flex-wrap: wrap; align-items: center; gap: 6px; margin-top: 12px; }
.dn-mark span { font-size: 13px; color: var(--paper-muted); margin-right: 4px; }
.dn-mark button {
  padding: 8px 12px; border-radius: calc(10px * var(--corner, 1)); border: 1.5px solid rgba(var(--paper-ink-rgb), .15); background: #fff; cursor: pointer;
  font: inherit; font-size: 13.5px; font-weight: 700; color: var(--paper-ink);
}
.dn-mark button:hover { border-color: var(--paper-ink); }
.dn-mark button[data-m="2"][aria-pressed="true"] { background: var(--ok); border-color: var(--ok); color: #fff; }
.dn-mark button[data-m="1"][aria-pressed="true"] { background: var(--warn); border-color: var(--warn); color: #fff; }
.dn-mark button[data-m="0"][aria-pressed="true"] { background: var(--crimson); border-color: var(--crimson); color: #fff; }
.dn-card[data-m="2"] { border-color: var(--ok); }
.dn-revisit { display: none; margin-top: 10px; font-size: 14px; font-weight: 700; color: var(--crimson); }
.dn-card[data-m="0"] .dn-revisit, .dn-card[data-m="1"] .dn-revisit { display: inline-block; }
.donow-teacher { margin-top: 14px; font-size: 14px; color: var(--paper-muted); }
.recall-prompt { font-weight: 700; color: var(--paper-ink); }
.l-sec .recall-tip { margin-top: 6px; font-size: 14.5px; color: var(--paper-muted); }
.recall-list { list-style: none; padding: 0; margin: 10px 0 0; display: grid; gap: 8px; }
.l-sec .recall-list li { margin: 0; }
.recall-list label { display: flex; gap: 10px; align-items: flex-start; cursor: pointer; font-size: 15.5px; line-height: 1.55; }
.recall-list input { flex: none; width: 18px; height: 18px; margin-top: 4px; accent-color: var(--ok); }
.l-sec .recall-score { font-weight: 700; color: var(--paper-ink); }
@media (max-width: 720px) { .donow { grid-template-columns: 1fr; } }

/* ---------- Self-assessment ---------- */
.rate-list { display: grid; gap: 10px; margin-top: 20px; }
.rate { display: grid; grid-template-columns: 1fr auto; gap: 14px; align-items: center; background: var(--paper-card); border: 1px solid var(--paper-line); border-radius: calc(16px * var(--corner, 1)); padding: 14px 16px; }
.rate p { margin: 0; font-size: 15.5px; }
.rate-btns { display: flex; gap: 6px; }
.rate-btns button { width: 44px; height: 44px; border-radius: calc(12px * var(--corner, 1)); border: 1.5px solid rgba(var(--paper-ink-rgb), .15); background: #fff; cursor: pointer; font-weight: 800; font-size: 15px; color: var(--paper-ink); transition: all .2s; }
.rate-btns button[data-r="1"][aria-pressed="true"] { background: var(--crimson); color: #fff; border-color: var(--crimson); box-shadow: 0 0 12px rgba(var(--crimson-rgb), .35); }
.rate-btns button[data-r="2"][aria-pressed="true"] { background: var(--warn); color: #fff; border-color: var(--warn); box-shadow: 0 0 12px rgba(var(--warn-rgb), .35); }
.rate-btns button[data-r="3"][aria-pressed="true"] { background: var(--ok); color: #fff; border-color: var(--ok); box-shadow: 0 0 12px rgba(var(--ok-rgb), .35); }
.rate-btns button[data-r="4"][aria-pressed="true"] { background: #2fb344; color: #fff; border-color: #2fb344; box-shadow: 0 0 12px rgba(47, 179, 68, .35); }
.rate-btns button:not([data-r])[aria-pressed="true"] { background: var(--paper-ink); color: var(--paper); border-color: var(--paper-ink); }
.rate-key { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 12px; font-size: 13px; color: var(--paper-muted); }

/* ---------- Assignment ---------- */
.assign-head { display: flex; flex-wrap: wrap; gap: 10px; align-items: center; margin-top: 18px; }
.aq { margin-top: 18px; background: var(--paper-card); border: 1px solid var(--paper-line); border-radius: var(--radius); padding: 20px; }
.aq-top { display: flex; gap: 12px; align-items: baseline; justify-content: space-between; }
.aq-top h4 { margin: 0; font-size: 16.5px; line-height: 1.5; }
.aq-top .marks { font-family: var(--font-mono); font-size: 12px; color: var(--paper-muted); white-space: nowrap; }
.aq ol.sub { margin: 8px 0 0; padding-left: 22px; }
.aq ol.sub li { font-size: 15.5px; margin: 4px 0; }
.aq .attempt-row { display: flex; align-items: center; gap: 10px; margin-top: 10px; font-size: 13.5px; color: var(--paper-muted); }
.mark-scheme { margin-top: 8px; font-size: 13.5px; color: var(--paper-muted); }
.mark-scheme b { color: var(--ok); }

.teacher { margin-top: 40px; }
.teacher summary { font-family: var(--font-mono); letter-spacing: .08em; text-transform: uppercase; font-size: 12.5px !important; }

/* ---------- Lesson footer ---------- */
.l-next { margin-top: 60px; display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.l-next a, .l-next div { display: block; text-decoration: none; padding: 24px; border-radius: var(--radius-lg); background: var(--paper-ink); color: var(--paper); }
.l-next small { font-family: var(--font-mono); font-size: 11px; letter-spacing: .12em; text-transform: uppercase; color: var(--paper-faint); }
.l-next b { display: block; font-family: var(--font-display); font-size: 1.5rem; font-weight: 600; margin-top: 6px; }
.l-next .soon { opacity: .6; }
.l-next a:hover { background: #2b2620; }

/* ---------- Responsive ---------- */
@media (max-width: 1060px) {
  .l-layout { grid-template-columns: minmax(0, 1fr); }
  .l-layout > * { min-width: 0; }
  .l-rail { position: sticky; top: 64px; z-index: 20; padding: 8px 0; margin: 0; border-radius: 0 0 14px 14px; background: rgba(var(--paper-rgb), .94); -webkit-backdrop-filter: blur(10px); backdrop-filter: blur(10px); border-bottom: 1px solid var(--paper-line); }
  .l-rail ol { display: flex; overflow-x: auto; padding: 0 4px; gap: 4px; scrollbar-width: none; }
  .l-rail ol::-webkit-scrollbar { display: none; }
  .l-rail a { white-space: nowrap; padding: 7px 10px; font-size: 13px; }
  .l-rail .rail-progress, .l-rail small { display: none; }
  .l-hero-grid { grid-template-columns: 1fr; }
  .story { grid-template-columns: 1fr; }
  .prac-head { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 720px) {
  .l-crumb { display: none; }
  .l-sec { padding-top: 56px; }
  .l-sec p, .l-sec li { font-size: 16px; }
  .grid-2, .grid-3 { grid-template-columns: 1fr; }
  .bins { grid-template-columns: 1fr; }
  .bin { min-height: 100px; }
  .fb-row { grid-template-columns: 22px 1fr; }
  .fb-row span:last-child { grid-column: 2; }
  .materials { columns: 1; }
  .qopts { grid-template-columns: 1fr; }
  .rate { grid-template-columns: 1fr; }
  .vt-cups { grid-template-columns: 1fr 1fr; gap: 10px; }
  /* Phones: two cards side by side leave ~100px for a 28px mono readout, so a line like
     "R = 0.50 Ω · I = 4.00 A" wrapped to five lines. Stack them and scale the readout. */
  @media (max-width: 560px) {
    .vt-cups { grid-template-columns: 1fr; gap: 10px; }
    .vt-count { font-size: 20px; margin-top: 8px; }
    .vt-count small { font-size: 11.5px; }
  }
  .vt-glass { width: 90px; height: 120px; }
  .l-next { grid-template-columns: 1fr; }
  .stage-hint { margin-left: 0; width: 100%; }
}

/* ---------- Print (assignment / notes) ---------- */
@media print {
  .nav, .l-rail, .narr-dock, .narr-spot, .narr-cue, .sparkle-layer, .stage, .sort, .vt, .l-hero .hero-cta, .progress, .no-print { display: none !important; }
  body.lesson-page, .l-hero { background: #fff !important; color: #000 !important; }
  .l-hero { padding: 20px 0; }
  .l-hero * { color: #000 !important; }
  .l-layout { display: block; }
  details.reveal-box { break-inside: avoid; }
  .reveal { opacity: 1 !important; transform: none !important; }
}

/* ---------- 3D story stage ---------- */
.story-stage .stage-canvas { height: clamp(400px, 54vw, 560px); }
.story-stage { background: linear-gradient(#5aa7e8, #ffd9a3); }
.story-bubble {
  position: absolute; z-index: 3; left: 50%; top: 40%; transform: translate(-50%, calc(-100% - 14px)) scale(.9); opacity: 0;
  width: max-content; max-width: min(320px, 70%); background: var(--paper-card); color: var(--paper-ink); padding: 12px 15px; border-radius: calc(16px * var(--corner, 1));
  font-size: 15px; line-height: 1.45; font-weight: 600; box-shadow: 0 16px 30px -12px rgba(0, 0, 0, .45);
  transition: opacity .35s var(--ease), transform .35s var(--ease); pointer-events: none;
}
.story-bubble.on { opacity: 1; transform: translate(-50%, calc(-100% - 14px)) scale(1); }
.story-bubble::after { content: ""; position: absolute; left: 50%; bottom: -9px; margin-left: -9px; border: 9px solid transparent; border-bottom: 0; border-top-color: var(--paper-card); }
.story-bubble b { display: block; font-family: var(--font-mono); font-size: 10.5px; letter-spacing: .12em; text-transform: uppercase; color: var(--crimson); margin-bottom: 3px; font-weight: 500; }
.story-caption {
  position: absolute; left: 16px; right: 16px; bottom: 14px; z-index: 3; text-align: center; font-family: var(--font-display); font-style: italic;
  font-size: clamp(15px, 1.6vw, 18px); color: #fff; text-shadow: 0 2px 10px rgba(0, 0, 0, .55); pointer-events: none;
}
.story-dots { display: flex; gap: 6px; }
.story-dots button { width: 10px; height: 10px; border-radius: 50%; border: 0; padding: 0; background: rgba(255, 255, 255, .22); cursor: pointer; }
.story-dots button.seen { background: rgba(var(--amber-rgb), .55); }
.story-dots button.on { background: var(--amber); transform: scale(1.3); }
.story-count { font-family: var(--font-mono); font-size: 12px; color: var(--muted); }
.story-stage .stage-label { color: rgba(255, 255, 255, .85); text-shadow: 0 1px 6px rgba(0, 0, 0, .4); }

/* ---------- Lesson 2 extras ---------- */
.prop-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 12px; margin-top: 22px; }
.prop { background: var(--paper-card); border: 1px solid var(--paper-line); border-radius: calc(16px * var(--corner, 1)); padding: 16px; }
.prop .ic { width: 36px; height: 36px; border-radius: calc(10px * var(--corner, 1)); display: grid; place-items: center; background: rgba(var(--ok-rgb), .12); color: var(--ok); font-weight: 800; }
.prop h4 { margin: 12px 0 0; font-size: 15px; }
.prop p { margin: 6px 0 0; font-size: 14px !important; line-height: 1.5; }
.word-cards { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 14px; margin-top: 22px; }
.word { border-radius: calc(18px * var(--corner, 1)); padding: 20px; color: #fff; position: relative; overflow: hidden; }
.word h4 { margin: 0; font-family: var(--font-display); font-size: 1.45rem; font-weight: 600; color: #fff; }
.word .say { font-family: var(--font-mono); font-size: 12px; opacity: .8; }
.word p { color: rgba(255, 255, 255, .9) !important; font-size: 15px !important; margin-top: 10px; }
.word .trick { margin-top: 12px; padding: 10px 12px; border-radius: calc(12px * var(--corner, 1)); background: rgba(255, 255, 255, .15); font-size: 14px; }
.predict { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 16px; }
.predict button { border: 1.5px solid rgba(var(--paper-ink-rgb), .2); background: #fffdf8; border-radius: calc(14px * var(--corner, 1)); padding: 14px 18px; font: inherit; font-weight: 700; cursor: pointer; color: var(--paper-ink); }
.predict button[aria-pressed="true"] { background: var(--paper-ink); color: var(--paper); border-color: var(--paper-ink); }
.predict-out { margin-top: 12px; font-size: 15px; color: var(--paper-muted); min-height: 1.5em; }

.toolkit { margin-top: 26px; background: var(--ink-900); color: var(--fg); border-radius: var(--radius-lg); padding: clamp(18px, 3vw, 30px); }
.toolkit h4 { color: var(--fg); margin: 0; font-size: 16px; }
.tk-row { display: grid; grid-template-columns: 1.1fr 1fr; gap: 20px; }
.tk-field { display: grid; gap: 6px; margin-top: 14px; }
.tk-field label { font-size: 12px; font-family: var(--font-mono); letter-spacing: .08em; text-transform: uppercase; color: var(--muted); }
.tk-field select, .tk-field input { font: inherit; font-size: 16px; padding: 12px 14px; border-radius: calc(12px * var(--corner, 1)); border: 1px solid var(--line-strong); background: rgba(255, 255, 255, .06); color: var(--fg); }
.tk-field select option { background: var(--ink-800); }
.mm-break { margin-top: 14px; display: flex; flex-wrap: wrap; gap: 8px; }
.mm-atom { padding: 8px 12px; border-radius: calc(12px * var(--corner, 1)); background: rgba(255, 255, 255, .06); font-family: var(--font-mono); font-size: 13.5px; }
.mm-atom b { color: var(--amber); font-weight: 500; }
.mm-total { margin-top: 12px; font-family: var(--font-display); font-size: 1.6rem; font-weight: 600; }
.mm-total small { font-family: var(--font-body); font-size: 13px; color: var(--muted); font-weight: 500; }
.working { margin-top: 14px; background: rgba(255, 255, 255, .05); border-radius: calc(14px * var(--corner, 1)); padding: 14px 16px; font-family: var(--font-mono); font-size: 14px; line-height: 1.9; color: var(--fg-soft); }
.working b { color: var(--teal); font-weight: 500; }
.working .res { color: var(--amber); }
.triangle { display: grid; place-items: center; margin-top: 10px; }
.triangle svg { width: 220px; height: auto; }

.steps-3d { display: flex; flex-wrap: wrap; gap: 6px; }
.steps-3d button { width: 34px; height: 34px; border-radius: calc(10px * var(--corner, 1)); border: 0; cursor: pointer; background: rgba(255, 255, 255, .07); color: var(--fg-soft); font-weight: 800; font-family: var(--font-mono); }
.steps-3d button[aria-current="step"] { background: var(--amber); color: var(--on-amber); }
.steps-3d button.done { background: rgba(var(--teal-rgb), .2); color: var(--teal); }
.step-panel { padding: 16px 18px; border-top: 1px solid var(--line); background: rgba(var(--ink-950-rgb), .5); }
.step-panel h4 { margin: 0; color: var(--fg); font-size: 16px; }
.step-panel p { margin: 6px 0 0 !important; color: var(--fg-soft) !important; font-size: 15px !important; max-width: none !important; }
.step-panel .why { color: var(--amber) !important; font-size: 14px !important; }

.calc-table input { width: 110px; font: inherit; font-size: 15px; padding: 8px 10px; border-radius: calc(10px * var(--corner, 1)); border: 1.5px solid rgba(var(--paper-ink-rgb), .18); background: #fff; }
.calc-out { font-family: var(--font-mono); font-size: 14px; }

.mistakes { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; margin-top: 18px; }
.mistake { background: var(--bad-tint-2); border: 1px solid rgba(var(--crimson-rgb), .25); border-radius: calc(16px * var(--corner, 1)); padding: 16px; }
.mistake h4 { margin: 0; font-size: 15px; color: var(--crimson); }
.mistake p { font-size: 14.5px !important; margin-top: 6px; }

.dil-readout { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 8px; padding: 14px 16px; border-top: 1px solid var(--line); }
.dil-readout div { background: rgba(255, 255, 255, .05); border-radius: calc(12px * var(--corner, 1)); padding: 10px 12px; }
.dil-readout span { display: block; font-family: var(--font-mono); font-size: 10.5px; letter-spacing: .1em; text-transform: uppercase; color: var(--muted); }
.dil-readout output { font-family: var(--font-mono); font-size: 18px; color: var(--fg); }
.dil-readout .hit output { color: var(--teal); }

@media (max-width: 1060px) { .prop-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); } .tk-row { grid-template-columns: 1fr; } }
@media (max-width: 720px) {
  .word-cards, .mistakes { grid-template-columns: 1fr; }
  .dil-readout { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .story-bubble { font-size: 13.5px; max-width: 78%; }
}

.seg button.seen::after { content: " ✓"; color: var(--teal); }
.seg button.seen[aria-pressed="true"]::after { color: var(--ok); }
#bal-note:not(.on) { color: var(--muted) !important; }

/* ---------- Lesson 3 components ---------- */
.glass-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 14px; margin-top: 22px; }
.glass-card { background: var(--paper-card); border: 1px solid var(--paper-line); border-radius: calc(18px * var(--corner, 1)); padding: 18px; position: relative; }
.glass-card .gi { width: 52px; height: 52px; border-radius: calc(14px * var(--corner, 1)); background: var(--paper-ink); display: grid; place-items: center; }
.glass-card .gi svg { width: 30px; height: 30px; }
.glass-card h4 { margin: 12px 0 0; font-size: 16px; }
.glass-card p { margin: 6px 0 0; font-size: 14.5px !important; line-height: 1.5; }
.glass-card .prec { position: absolute; top: 16px; right: 16px; font-family: var(--font-mono); font-size: 11px; padding: 4px 8px; border-radius: calc(8px * var(--corner, 1)); background: rgba(var(--ok-rgb), .12); color: var(--ok); }
.rule-banner { margin-top: 22px; display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 12px; }
.rule { border-radius: calc(18px * var(--corner, 1)); padding: 18px; color: #fff; }
.rule b { display: block; font-family: var(--font-display); font-size: 1.3rem; font-weight: 600; }
.rule span { display: block; margin-top: 6px; font-size: 14.5px; opacity: .92; }
.rinse-controls { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 10px; padding: 14px 16px; border-top: 1px solid var(--line); }
.rinse-controls label { display: grid; gap: 6px; font-family: var(--font-mono); font-size: 11px; letter-spacing: .08em; text-transform: uppercase; color: var(--muted); }
.rinse-controls select { font: inherit; font-size: 14.5px; padding: 10px 12px; border-radius: calc(12px * var(--corner, 1)); border: 1px solid var(--line-strong); background: rgba(255, 255, 255, .06); color: var(--fg); text-transform: none; letter-spacing: 0; }
.rinse-controls select option { background: var(--ink-800); }
.rinse-extra { display: flex; flex-wrap: wrap; gap: 16px; align-items: center; padding: 0 16px 14px; color: var(--fg-soft); font-size: 14px; }
.rinse-extra label { display: inline-flex; gap: 8px; align-items: center; cursor: pointer; }
.rinse-result { display: none; padding: 16px; border-top: 1px solid var(--line); gap: 8px; }
.rinse-result.on { display: grid; animation: panel-in .5s var(--ease); }
.rr-head { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 8px; margin-bottom: 4px; }
.rr-head div { background: rgba(255, 255, 255, .05); border-radius: calc(12px * var(--corner, 1)); padding: 10px 12px; }
.rr-head span { display: block; font-family: var(--font-mono); font-size: 10.5px; letter-spacing: .1em; text-transform: uppercase; color: var(--muted); }
.rr-head b { font-family: var(--font-mono); font-size: 17px; color: var(--fg); font-weight: 500; }
.rr-head .good b { color: var(--teal); } .rr-head .bad b { color: var(--pink-soft); }
.reader-wrap { display: grid; grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr); }
.reader-side { padding: 16px; border-left: 1px solid var(--line); background: var(--paper); color: var(--paper-ink); display: flex; flex-direction: column; gap: 10px; }
.reader-side h4 { margin: 0; font-size: 14px; font-family: var(--font-mono); letter-spacing: .08em; text-transform: uppercase; color: var(--paper-muted); }
.reader-side svg { width: 100%; max-width: 260px; height: auto; align-self: center; }
.rd-controls { display: flex; flex-wrap: wrap; gap: 10px; align-items: center; padding: 14px 16px; border-top: 1px solid var(--line); }
.rd-controls input[type=text] { width: 120px; font-family: var(--font-mono); font-size: 18px; padding: 9px 12px; border-radius: calc(12px * var(--corner, 1)); border: 1px solid var(--line-strong); background: rgba(255, 255, 255, .08); color: var(--fg); }
.eye-range { display: flex; align-items: center; gap: 8px; color: var(--fg-soft); font-size: 13px; font-weight: 700; }
.eye-range input { width: 150px; accent-color: var(--amber); }
.rd-fb { padding: 12px 16px; border-top: 1px solid var(--line); font-size: 14.5px; color: var(--fg-soft); }
.rd-fb.good { color: #bff5e6; background: rgba(var(--ok-rgb), .15); }
.rd-fb.bad { color: #ffd3dc; background: rgba(var(--crimson-rgb), .15); }
.rd-fb strong { color: #fff; }
.skills { margin-top: 22px; background: var(--paper-ink); color: var(--paper); border-radius: var(--radius-lg); padding: 22px; }
.skills.complete { box-shadow: 0 0 0 3px var(--ok); }
.skills h4 { margin: 0; color: var(--amber); font-family: var(--font-mono); font-size: 12px; letter-spacing: .12em; text-transform: uppercase; display: flex; justify-content: space-between; }
.skills label { display: grid; grid-template-columns: 28px 1fr; gap: 10px; align-items: start; padding: 10px 0; border-bottom: 1px solid rgba(var(--paper-rgb), .1); font-size: 15px; cursor: pointer; color: #e8e0d0; }
.skills label:last-child { border-bottom: 0; }
.skills input { width: 22px; height: 22px; accent-color: var(--ok); margin-top: 1px; }
.pt-item { margin-top: 14px; background: var(--paper-card); border: 1px solid var(--paper-line); border-radius: calc(16px * var(--corner, 1)); padding: 16px; }
.pt-item p.pt-q { margin: 0; font-weight: 700; font-size: 15px; }
.pt-opts { display: grid; gap: 8px; margin-top: 10px; }
.pt-opts button { text-align: left; border: 1.5px solid rgba(var(--paper-ink-rgb), .14); background: #fff; border-radius: calc(12px * var(--corner, 1)); padding: 10px 14px; font: inherit; font-size: 15px; cursor: pointer; color: var(--paper-ink); }
.pt-opts button.correct { border-color: var(--ok); background: var(--ok-tint); }
.pt-opts button.incorrect { border-color: var(--crimson); background: var(--bad-tint); }
.pt-why { display: none; margin-top: 10px; font-size: 14.5px; color: var(--paper-muted); }
.pt-why.on { display: block; }
.during-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; margin-top: 18px; }
.class-table input { width: 90px; font: inherit; font-size: 15px; padding: 7px 9px; border-radius: calc(10px * var(--corner, 1)); border: 1.5px solid rgba(var(--paper-ink-rgb), .18); background: #fff; font-family: var(--font-mono); }
@media (max-width: 1060px) { .reader-wrap { grid-template-columns: 1fr; } .reader-side { border-left: 0; border-top: 1px solid var(--line); } }
@media (max-width: 720px) {
  .glass-grid, .rule-banner, .rinse-controls, .during-grid { grid-template-columns: 1fr; }
  .rr-head { grid-template-columns: 1fr; }
}
.l-sec .fb-row strong, .l-sec .rinse-result strong, .l-sec .rd-fb strong, .l-sec .stage strong, .l-sec .sort strong, .l-sec .vt strong, .l-sec .toolkit strong { color: #fff; }

/* ---------- Lesson 4 components ---------- */
.titr-wrap { display: grid; grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr); }
.titr-chart-box { background: var(--paper-card); border-left: 1px solid var(--line); padding: 12px; display: flex; flex-direction: column; }
.titr-chart-box canvas { width: 100%; height: clamp(300px, 34vw, 400px); flex: none; display: block; }
.titr-chart-box .chart-lab { font-family: var(--font-mono); font-size: 11.5px; color: var(--paper-muted); padding: 2px 4px 8px; }
.titr-read { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 8px; padding: 14px 16px; border-top: 1px solid var(--line); }
.titr-read div { background: rgba(255, 255, 255, .05); border-radius: calc(12px * var(--corner, 1)); padding: 10px 12px; }
.titr-read span { display: block; font-family: var(--font-mono); font-size: 10.5px; letter-spacing: .1em; text-transform: uppercase; color: var(--muted); }
.titr-read output { font-family: var(--font-mono); font-size: 17px; color: var(--fg); display: flex; align-items: center; }
.hin-eq { font-family: var(--font-mono); font-size: clamp(16px, 2vw, 22px); text-align: center; padding: 16px; border-top: 1px solid var(--line); color: var(--fg-soft); }
.hin-eq .l, .hin-eq .r { padding: 4px 10px; border-radius: calc(10px * var(--corner, 1)); transition: background .4s, color .4s; }
.hin-eq.left .l { background: rgba(var(--amber-rgb), .2); color: #fff; }
.hin-eq.right .r { background: rgba(var(--pink-rgb), .25); color: #fff; }
.hin-read { display: flex; flex-wrap: wrap; gap: 14px; align-items: center; padding: 0 16px 14px; color: var(--fg-soft); font-size: 14px; }
.hin-read .big-sw { width: 34px; height: 34px; border-radius: 50%; box-shadow: inset 0 -6px 10px rgba(0,0,0,.15), 0 0 0 1px var(--line-strong); transition: background .4s; }
.chooser { margin-top: 20px; display: grid; gap: 10px; }
.ch-row { background: var(--paper-card); border: 1px solid var(--paper-line); border-radius: calc(16px * var(--corner, 1)); padding: 14px 16px; display: grid; grid-template-columns: 1fr auto; gap: 10px; align-items: center; }
.ch-row.ok { border-color: var(--ok); background: var(--ok-tint-2); } .ch-row.no { border-color: var(--crimson); background: var(--bad-tint); }
.ch-row b { font-size: 15.5px; } .ch-row small { display: block; color: var(--paper-muted); font-family: var(--font-mono); font-size: 12px; }
.ch-row select { font: inherit; font-size: 14.5px; padding: 9px 12px; border-radius: calc(10px * var(--corner, 1)); border: 1.5px solid rgba(var(--paper-ink-rgb),.18); background: #fff; }
.ch-why { grid-column: 1 / -1; display: none; font-size: 14.5px; color: var(--paper-muted); }
.ch-why.on { display: block; }
.ph-data { min-width: 900px; font-family: var(--font-mono); font-size: 13px; }
.ph-data th, .ph-data td { padding: 8px 9px !important; text-align: center !important; }
.pick-wrap { margin-top: 16px; border-radius: calc(18px * var(--corner, 1)); border: 1px solid var(--paper-line); overflow: hidden; background: var(--paper-card); }
.pick-wrap canvas { width: 100%; height: 340px; display: block; cursor: crosshair; }
.pick-fb { padding: 12px 16px; border-top: 1px solid var(--paper-line); font-size: 15px; }
.pick-fb.good { background: var(--ok-tint); } .pick-fb.bad { background: var(--bad-tint-2); }
.curve-anatomy { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 12px; margin-top: 18px; }
@media (max-width: 1060px) { .titr-wrap { grid-template-columns: 1fr; } .titr-chart-box { border-left: 0; border-top: 1px solid var(--line); } .curve-anatomy { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
@media (max-width: 720px) { .titr-read { grid-template-columns: repeat(2, minmax(0, 1fr)); } .ch-row { grid-template-columns: 1fr; } .curve-anatomy { grid-template-columns: 1fr; } }

/* ---------- Lesson 5 components ---------- */
.zoom-box { background: var(--paper-card); border-left: 1px solid var(--line); padding: 12px; display: flex; flex-direction: column; }
.zoom-box .chart-lab { font-family: var(--font-mono); font-size: 11.5px; color: var(--paper-muted); padding: 2px 4px 8px; }
.zoom-box canvas { width: 100%; height: clamp(320px, 38vw, 430px); display: block; border-radius: calc(14px * var(--corner, 1)); }
#run-stage .titr-wrap { grid-template-columns: minmax(0, 1.25fr) minmax(0, 0.75fr); }
.bar-lab { font-family: var(--font-mono); font-size: 10.5px; letter-spacing: .12em; text-transform: uppercase; color: var(--muted); min-width: 64px; }
#run-stage .rd-fb b { color: #fff; }
.ep-strip { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 12px; margin-top: 20px; }
.ep-strip > div { background: var(--paper-card); border: 1px solid var(--paper-line); border-radius: calc(16px * var(--corner, 1)); padding: 14px 16px 14px 60px; position: relative; }
.ep-strip i { position: absolute; left: 14px; top: 14px; width: 32px; height: 32px; border-radius: 50%; background: var(--c); box-shadow: inset 0 -6px 10px rgba(0,0,0,.15); }
.ep-strip b { display: block; font-size: 15.5px; } .ep-strip span { font-size: 14px; color: var(--paper-muted); }
.ep-strip .hit { border-color: #ff8a2f; box-shadow: 0 0 0 3px rgba(255, 138, 47, .18); }
.rt { margin-top: 18px; background: var(--paper-card); border: 1px solid var(--paper-line); border-radius: var(--radius); padding: 18px; }
.rt-meta { display: flex; flex-wrap: wrap; gap: 12px 24px; align-items: center; font-weight: 700; font-size: 14.5px; }
.rt-meta label { display: inline-flex; align-items: center; gap: 8px; }
.rt select, .rt-in { font: inherit; font-family: var(--font-mono); font-size: 14.5px; padding: 8px 10px; border-radius: calc(10px * var(--corner, 1)); border: 1.5px solid rgba(var(--paper-ink-rgb),.18); background: #fff; color: var(--paper-ink); }
.rt select { font-family: var(--font-body, inherit); }
.rt-in { width: 100%; min-width: 72px; text-align: center; }
.rt-in.sm { width: 116px; }
.rt-in.good { border-color: var(--ok); background: var(--ok-tint-2); } .rt-in.bad { border-color: var(--crimson); background: var(--bad-tint); }
.rt-tbl th:first-child, .rt-model th:first-child, .nb-tbl th:first-child { text-align: left; white-space: nowrap; }
.rt-tbl td { padding: 6px !important; min-width: 84px; }
.rt-model td { font-family: var(--font-mono); text-align: center; }
.rt-avg { display: flex; flex-wrap: wrap; gap: 10px; align-items: center; margin-top: 14px; font-size: 14.5px; font-weight: 700; }
.chip-tog { display: inline-flex; align-items: center; gap: 6px; padding: 6px 10px; border-radius: 999px; border: 1px solid var(--paper-line); background: #fff; cursor: pointer; font-weight: 700; }
.rt-avg-in { display: inline-flex; align-items: center; gap: 8px; margin-left: auto; }
.rt-avg-in .rt-in { width: 96px; }
.rt .sort-score { color: var(--paper-ink); font-weight: 700; }
.rt .btn-ghost, .audit-side .btn-ghost { color: var(--paper-ink); box-shadow: inset 0 0 0 1px var(--paper-line); }
.rt-report { list-style: none; padding: 0; margin: 14px 0 0; display: grid; gap: 6px; }
.rt-report li { display: grid; grid-template-columns: 26px 1fr; gap: 8px; padding: 9px 12px; border-radius: calc(12px * var(--corner, 1)); font-size: 14.5px; }
.rt-report li.ok { background: var(--ok-tint); } .rt-report li.no { background: var(--bad-tint-2); } .rt-report li.note { background: #fff7e0; }
.rt-report li > b { font-size: 15px; } .rt-report li.ok > b { color: var(--ok); } .rt-report li.no > b { color: var(--crimson); }
.rt-report small { display: block; color: var(--paper-muted); font-size: 13.5px; margin-top: 2px; }
.rule-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 12px; margin-top: 20px; }
.rcard { background: var(--paper-card); border: 1px solid var(--paper-line); border-radius: calc(16px * var(--corner, 1)); padding: 16px 16px 14px; position: relative; }
.rcard > b { position: absolute; right: 14px; top: 10px; font-family: var(--font-display); font-size: 2rem; color: rgba(var(--paper-ink-rgb),.12); }
.rcard h4 { margin: 0 0 4px; font-size: 16px; } .rcard p { margin: 0; font-size: 14.5px; color: var(--paper-muted); }
.audit { display: grid; grid-template-columns: minmax(0, 1fr); gap: 14px; margin-top: 20px; }
.nb { background: repeating-linear-gradient(#fffdf7 0 31px, #dfe9f7 31px 32px); border: 1px solid var(--paper-line); border-radius: calc(16px * var(--corner, 1)); padding: 18px 18px 18px 46px; position: relative; font-family: var(--font-mono); font-size: 14.5px; }
.nb::before { content: ""; position: absolute; left: 30px; top: 0; bottom: 0; width: 2px; background: rgba(var(--crimson-rgb), .35); }
.nb .tbl-wrap { margin: 8px 0; background: transparent; }
.nb-tbl { background: rgba(255,255,255,.6); } .nb-tbl td { text-align: center; }
.nb-line { margin: 6px 0; font-size: 14.5px !important; }
[data-bug], [data-fine] { cursor: pointer; border-radius: calc(6px * var(--corner, 1)); padding: 1px 4px; transition: background .2s, box-shadow .2s; }
[data-bug]:hover, [data-fine]:hover { background: rgba(var(--amber-rgb), .2); }
[data-bug].caught { background: rgba(var(--crimson-rgb), .14); box-shadow: inset 0 0 0 2px var(--crimson); color: var(--crimson); font-weight: 700; }
[data-fine].fine { background: rgba(var(--ok-rgb), .16); }
.audit-side { background: var(--paper-card); border: 1px solid var(--paper-line); border-radius: calc(16px * var(--corner, 1)); padding: 16px; display: flex; flex-direction: column; gap: 10px; }
.audit-count { font-family: var(--font-mono); font-size: 15px; }
.audit-found { margin: 0; padding-left: 20px; font-size: 14px; display: grid; gap: 6px; }
.audit-fix { display: none; margin-top: 16px; background: var(--ok-tint-2); border: 1px solid rgba(var(--ok-rgb),.3); border-radius: calc(16px * var(--corner, 1)); padding: 16px 18px; }
.audit-fix.on { display: block; animation: panel-in .5s var(--ease); }
.audit-fix h4 { margin: 0 0 6px; }
.drill { display: grid; gap: 10px; margin-top: 20px; }
.dr-row { background: var(--paper-card); border: 1px solid var(--paper-line); border-radius: calc(16px * var(--corner, 1)); padding: 14px 16px; display: grid; grid-template-columns: 1fr auto; gap: 10px; align-items: center; }
.dr-row.ok { border-color: var(--ok); background: var(--ok-tint-2); } .dr-row.no { border-color: var(--crimson); background: var(--bad-tint); }
.dr-set { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; }
.dr-set > b { margin-right: 4px; }
.dr-chip { font: inherit; font-family: var(--font-mono); font-size: 13.5px; padding: 7px 11px; border-radius: 999px; border: 1.5px solid rgba(var(--paper-ink-rgb),.18); background: #fff; cursor: pointer; color: var(--paper-ink); }
.dr-chip.rough { border-style: dashed; color: var(--paper-muted); }
.dr-chip.none { font-family: inherit; font-weight: 700; }
.dr-chip[aria-pressed="true"] { background: var(--paper-ink); color: var(--paper); border-color: var(--paper-ink); }
.dr-avg { display: inline-flex; align-items: center; gap: 8px; font-weight: 700; font-size: 14.5px; }
.dr-avg input { font: inherit; font-family: var(--font-mono); width: 92px; padding: 8px 10px; border-radius: calc(10px * var(--corner, 1)); border: 1.5px solid rgba(var(--paper-ink-rgb),.18); text-align: center; }
.dr-why { grid-column: 1 / -1; display: none; margin: 0; font-size: 14.5px !important; color: var(--paper-muted); }
.dr-why.on { display: block; }
.exam-q { margin-top: 20px; background: #fff; border: 1px solid var(--paper-line); border-left: 5px solid var(--paper-ink); border-radius: calc(14px * var(--corner, 1)); padding: 18px 20px; font-family: var(--font-display); }
.exam-q small { font-family: var(--font-mono); font-size: 11px; letter-spacing: .12em; text-transform: uppercase; color: var(--paper-muted); }
.exam-q p { margin: 8px 0 0; font-size: 17px !important; line-height: 1.6; }
.exam-q .marks { font-family: var(--font-mono); font-size: 12px; color: var(--paper-muted); }
.exam-q .muted { color: var(--paper-muted); font-size: 15px !important; }
@media (max-width: 1060px) { #run-stage .titr-wrap { grid-template-columns: 1fr; } .zoom-box { border-left: 0; border-top: 1px solid var(--line); } .zoom-box canvas { height: 300px; } .audit { grid-template-columns: 1fr; } .rule-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
@media (max-width: 720px) { .rt-tbl th:first-child { white-space: normal; min-width: 96px; } .rt-tbl td { min-width: 70px; } .rt-in { min-width: 60px; padding: 8px 4px; } .ep-strip, .rule-grid { grid-template-columns: 1fr; } .dr-row { grid-template-columns: 1fr; } .rt-avg-in { margin-left: 0; } .bar-lab { width: 100%; } .nb { padding-left: 38px; } .nb::before { left: 24px; } }
.audit-side .btn { align-self: flex-start; }

/* ---------- Lesson 6 components ---------- */
.formula-art { position: relative; display: grid; gap: 12px; padding: 30px 0 10px; justify-items: center; }
.formula-art .halo { position: absolute; inset: 0; background: radial-gradient(circle at 50% 50%, rgba(var(--violet-rgb), .3), transparent 60%); filter: blur(10px); z-index: -1; }
.fa-card { font-family: var(--font-mono); font-size: clamp(14px, 1.6vw, 17px); color: var(--fg); padding: 12px 18px; border-radius: calc(14px * var(--corner, 1)); background: rgba(255, 255, 255, .06); box-shadow: inset 0 0 0 1px var(--line-strong); animation: cup-bob 5s ease-in-out infinite; animation-delay: var(--dl, 0s); white-space: nowrap; }
.fa-card span { color: var(--amber); margin-right: 8px; font-weight: 600; }
.fa-card:nth-child(odd) { transform: translateX(-18px); }
.road { display: grid; grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr) auto minmax(0, 1fr) auto minmax(0, 1fr); gap: 8px; align-items: stretch; margin-top: 22px; }
.rd { background: var(--paper-card); border: 1px solid var(--paper-line); border-radius: calc(16px * var(--corner, 1)); padding: 14px; position: relative; }
.rd > b { display: inline-grid; place-items: center; width: 26px; height: 26px; border-radius: calc(8px * var(--corner, 1)); background: var(--paper-ink); color: var(--paper); font-size: 13px; }
.rd h4 { margin: 8px 0 4px; font-size: 15.5px; } .rd p { margin: 0; font-family: var(--font-mono); font-size: 14px !important; }
.rd small { display: block; margin-top: 4px; color: var(--paper-muted); font-size: 12.5px; }
.rd.hot { border-color: var(--violet); box-shadow: 0 0 0 3px rgba(var(--violet-rgb), .18); }
.rd-arrow { align-self: center; font-size: 22px; color: var(--paper-muted); }
.legend { position: absolute; left: 12px; bottom: 12px; display: flex; flex-wrap: wrap; gap: 6px; max-width: calc(100% - 24px); z-index: 2; pointer-events: none; }
.legend span { font-family: var(--font-mono); font-size: 11.5px; color: var(--fg); background: rgba(var(--ink-950-rgb), .6); padding: 4px 8px 4px 22px; border-radius: 999px; position: relative; }
.legend span::before { content: ""; position: absolute; left: 7px; top: 50%; width: 10px; height: 10px; margin-top: -5px; border-radius: 50%; background: var(--c); }
.bas-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 12px; margin-top: 20px; }
.bas { background: var(--paper-card); border: 1px solid var(--paper-line); border-top: 5px solid var(--c); border-radius: calc(16px * var(--corner, 1)); padding: 16px; position: relative; }
.bas > b { position: absolute; right: 14px; top: 6px; font-family: var(--font-display); font-size: 2.6rem; color: var(--c); opacity: .5; }
.bas h4 { margin: 0 0 6px; } .bas p { margin: 0; font-family: var(--font-mono); font-size: 14px !important; line-height: 1.8; }
.bas small { font-family: var(--font-body, inherit); color: var(--paper-muted); }
.worked { display: grid; gap: 14px; margin-top: 20px; }
.wk { background: var(--paper-card); border: 1px solid var(--paper-line); border-radius: var(--radius); padding: 18px 20px; }
.wk h4 { margin: 0; } .wk-q { margin: 8px 0 0; font-size: 15.5px; font-weight: 600; }
.wk-steps { margin: 12px 0 0; padding-left: 22px; display: grid; gap: 6px; }
.wk-steps li { display: none; font-size: 15px; line-height: 1.6; padding: 6px 10px; border-radius: calc(10px * var(--corner, 1)); background: rgba(var(--violet-rgb), .08); }
.wk-steps li.on { display: list-item; animation: panel-in .45s var(--ease); }
.wk-bar { display: flex; flex-wrap: wrap; gap: 10px; align-items: center; margin-top: 12px; }
.wk-count { font-family: var(--font-mono); font-size: 13px; color: var(--paper-muted); }
.wk .btn-ghost, .dark-ghost { color: var(--paper-ink) !important; box-shadow: inset 0 0 0 1px var(--paper-line) !important; }
.mt { margin-top: 20px; background: var(--paper-card); border: 1px solid var(--paper-line); border-radius: var(--radius); padding: 18px 20px; }
.mt-top { display: flex; flex-wrap: wrap; gap: 8px 16px; align-items: center; font-weight: 700; }
.mt-top label { display: inline-flex; align-items: center; gap: 8px; } .mt-top .rt-in { width: 100px; }
.mt-top small { font-weight: 500; color: var(--paper-muted); font-size: 13.5px; }
.mt .eq { margin-top: 14px; }
.mt-steps { list-style: none; counter-reset: s; padding: 0; margin: 14px 0 0; display: grid; gap: 8px; }
.mt-steps li { counter-increment: s; display: grid; grid-template-columns: 1fr auto; gap: 12px; align-items: center; padding: 10px 12px 10px 46px; border-radius: calc(12px * var(--corner, 1)); background: #fff; border: 1px solid var(--paper-line); position: relative; font-size: 15px; }
.mt-steps li::before { content: counter(s); position: absolute; left: 12px; top: 50%; transform: translateY(-50%); width: 24px; height: 24px; border-radius: calc(7px * var(--corner, 1)); display: grid; place-items: center; background: var(--paper-ink); color: var(--paper); font-size: 12.5px; font-weight: 700; }
.mt-steps label { display: inline-flex; align-items: center; gap: 8px; font-family: var(--font-mono); font-size: 13px; color: var(--paper-muted); white-space: nowrap; }
.mt-steps .rt-in { width: 130px; }
.mt .sort-score { color: var(--paper-ink); font-weight: 700; }
.mt-hint { font-size: 13.5px !important; color: var(--paper-muted); margin: 8px 0 0; }
.mt-sol { display: none; margin-top: 14px; background: var(--ok-tint-2); border: 1px solid rgba(var(--ok-rgb),.3); border-radius: calc(14px * var(--corner, 1)); padding: 14px 16px; font-size: 15px; }
.mt-sol.on { display: block; animation: panel-in .5s var(--ease); }
.mt-sol h4 { margin: 0 0 6px; } .mt-sol ol { margin: 0; padding-left: 20px; display: grid; gap: 4px; }
.mt-verdict { display: none; margin: 14px 0 0; padding: 14px 16px; border-radius: calc(14px * var(--corner, 1)); background: var(--paper-ink); color: var(--paper); font-size: 15.5px !important; }
.mt-verdict.on { display: block; } .mt-verdict b { color: var(--amber); }
#mx-titre-row b { color: #fff; font-family: var(--font-mono); }
.mx-how { margin: 12px 0 0; padding-left: 22px; display: grid; gap: 6px; font-size: 15.5px; }
.mx-tbl th small { display: block; font-family: var(--font-mono); font-size: 11.5px; color: var(--paper-muted); font-weight: 500; text-transform: none; letter-spacing: 0; }
.mx-tbl td { text-align: center; } .mx-tbl .mx-t { font-family: var(--font-mono); font-weight: 700; }
.mx-tbl select { font: inherit; font-size: 14px; padding: 8px 10px; border-radius: calc(10px * var(--corner, 1)); border: 1.5px solid rgba(var(--paper-ink-rgb),.18); background: #fff; }
.mx-tbl select.good { border-color: var(--ok); background: var(--ok-tint-2); } .mx-tbl select.bad { border-color: var(--crimson); background: var(--bad-tint); }
.mx-tbl .rt-in { width: 110px; }
.practice { display: grid; gap: 10px; margin-top: 20px; }
.pq { background: var(--paper-card); border: 1px solid var(--paper-line); border-radius: calc(16px * var(--corner, 1)); padding: 14px 16px; display: grid; grid-template-columns: 1fr auto; gap: 10px; align-items: center; }
.pq.ok { border-color: var(--ok); background: var(--ok-tint-2); } .pq.no { border-color: var(--crimson); background: var(--bad-tint); }
.pq p { margin: 0; font-size: 15px !important; }
.pq-in { display: inline-flex; align-items: center; gap: 8px; font-family: var(--font-mono); font-size: 13px; color: var(--paper-muted); white-space: nowrap; }
.pq-in .rt-in { width: 120px; }
.pq-sol { grid-column: 1 / -1; display: none; color: var(--paper-muted); font-size: 14.5px !important; }
.pq-sol.on { display: block; }
@media (max-width: 1060px) { .road { grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); } .rd-arrow { display: none; } }
@media (max-width: 720px) { .road, .bas-grid { grid-template-columns: 1fr; } .mt-steps li, .pq { grid-template-columns: 1fr; } .fa-card:nth-child(odd) { transform: none; } .fa-card { white-space: normal; } .legend span { font-size: 10.5px; } }

/* ---------- Lesson 7 components ---------- */
.jig-art { position: relative; display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 12px; padding: 40px 0 10px; }
.jig-art .halo { position: absolute; inset: 0; background: radial-gradient(circle at 50% 55%, rgba(var(--teal-rgb), .25), transparent 60%); filter: blur(10px); z-index: -1; }
.jp { aspect-ratio: 1; border-radius: calc(22px * var(--corner, 1)); background: rgba(255, 255, 255, .05); box-shadow: inset 0 0 0 2px var(--c); display: grid; place-content: center; text-align: center; animation: cup-bob 5s ease-in-out infinite; animation-delay: var(--dl, 0s); position: relative; }
.jp::after { content: ""; position: absolute; right: -16px; top: 50%; width: 24px; height: 24px; margin-top: -12px; border-radius: 50%; background: var(--c); opacity: .9; }
.jp:last-child::after { display: none; }
.jp b { font-family: var(--font-display); font-size: clamp(2.2rem, 4vw, 3.2rem); color: var(--c); line-height: 1; }
.jp span { font-family: var(--font-mono); font-size: 11.5px; color: var(--fg-soft); margin-top: 6px; }
.jig-steps { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 12px; margin-top: 20px; }
.js { background: var(--paper-card); border: 1px solid var(--paper-line); border-radius: calc(16px * var(--corner, 1)); padding: 16px; }
.js > b { display: inline-grid; place-items: center; width: 28px; height: 28px; border-radius: 50%; background: var(--paper-ink); color: var(--paper); font-size: 13px; }
.js h4 { margin: 8px 0 4px; font-size: 15.5px; } .js p { margin: 0; font-size: 14.5px !important; color: var(--paper-muted); }
.jig-tools { margin-top: 18px; background: var(--paper-card); border: 1px solid var(--paper-line); border-radius: var(--radius); padding: 16px 18px; display: grid; gap: 12px; }
.roles { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; font-weight: 700; }
.roles button, .st-tabs button { font: inherit; font-weight: 700; font-size: 14px; padding: 9px 14px; border-radius: 999px; border: 1.5px solid rgba(var(--paper-ink-rgb),.18); background: #fff; cursor: pointer; color: var(--paper-ink); }
.roles .r-a[aria-pressed="true"], .st-tabs .t-a[aria-selected="true"] { background: var(--amber); border-color: var(--amber); }
.roles .r-b[aria-pressed="true"], .st-tabs .t-b[aria-selected="true"] { background: var(--violet); border-color: var(--violet); color: #fff; }
.roles .r-c[aria-pressed="true"], .st-tabs .t-c[aria-selected="true"] { background: var(--teal); border-color: var(--teal); }
.role-out { margin: 0; font-size: 15px !important; min-height: 1.4em; }
.jtimer { display: flex; flex-wrap: wrap; gap: 10px; align-items: center; }
.jtimer select { font: inherit; font-size: 14px; padding: 8px 10px; border-radius: calc(10px * var(--corner, 1)); border: 1.5px solid rgba(var(--paper-ink-rgb),.18); background: #fff; }
.jtimer output { font-family: var(--font-mono); font-size: 28px; font-weight: 600; min-width: 5ch; }
.jtimer output.low { color: var(--crimson); }
.st-tabs { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 18px; position: sticky; top: 72px; z-index: 6; padding: 8px 0; background: linear-gradient(var(--paper) 70%, transparent); }
.st-tabs button.mastered::after { content: " ✓"; }
.st-panel { margin-top: 8px; }
.st-panel > h3 { margin-top: 10px; }
.st-h { margin: 26px 0 0; }
.pur-bar { height: 12px; margin: 0 16px 12px; border-radius: calc(99px * var(--corner, 1)); background: #a9814f; overflow: hidden; }
.pur-bar i { display: block; height: 100%; background: linear-gradient(90deg, #fff, #ffe9a8); transition: width .3s; }
.pur-bar.water { background: var(--violet); } .pur-bar.water i { background: #e2453c; }
.teach-card { margin-top: 20px; border-radius: var(--radius); padding: 18px 20px; background: var(--paper-ink); color: var(--paper); border-top: 6px solid var(--amber); }
.teach-card.t-b { border-top-color: var(--violet); } .teach-card.t-c { border-top-color: var(--teal); }
.teach-card h4 { margin: 0 0 8px; color: var(--paper); }
.teach-card ul { list-style: none; padding: 0; margin: 0; display: grid; gap: 8px; }
.teach-card label { display: grid; grid-template-columns: 22px 1fr; gap: 8px; align-items: start; font-size: 15px; color: var(--on-ink-soft); cursor: pointer; }
.teach-card input { margin-top: 4px; accent-color: var(--lime); }
.st-tag { display: inline-grid; place-items: center; width: 24px; height: 24px; border-radius: calc(7px * var(--corner, 1)); font-weight: 800; font-size: 13px; margin-right: 4px; }
.st-A { background: var(--amber); } .st-B { background: var(--violet); color: #fff; } .st-C { background: var(--teal); }
@media (max-width: 1060px) { .jig-steps { grid-template-columns: repeat(2, minmax(0, 1fr)); } .st-tabs { top: 112px; } }
@media (max-width: 720px) { .jig-steps { grid-template-columns: 1fr; } .jp::after { display: none; } }

/* ---------- Lesson 8 components ---------- */
.change-art { position: relative; display: grid; gap: 10px; padding: 34px 0 10px; justify-items: stretch; max-width: 340px; margin: 0 auto; }
.change-art .halo { position: absolute; inset: 0; background: radial-gradient(circle at 50% 50%, rgba(var(--amber-rgb), .25), transparent 60%); filter: blur(10px); z-index: -1; }
.ca-row { display: flex; justify-content: space-between; align-items: baseline; gap: 12px; padding: 12px 16px; border-radius: calc(14px * var(--corner, 1)); background: rgba(255, 255, 255, .06); box-shadow: inset 0 0 0 1px var(--line-strong); animation: cup-bob 5s ease-in-out infinite; }
.ca-row span { font-family: var(--font-mono); font-size: 12px; letter-spacing: .1em; text-transform: uppercase; color: var(--muted); }
.ca-row b { font-family: var(--font-mono); color: var(--fg); font-size: 17px; }
.ca-row.minus { animation-delay: .4s; } .ca-row.minus b::before { content: "− "; color: var(--pink); }
.ca-row.eq { animation-delay: .8s; box-shadow: inset 0 0 0 2px var(--amber); } .ca-row.eq b { color: var(--amber); }
.change-art small { text-align: center; color: var(--muted); font-family: var(--font-mono); font-size: 11px; }
.analogy { display: grid; grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr); gap: 12px; align-items: center; margin-top: 20px; }
.an-col { background: var(--paper-card); border: 1px solid var(--paper-line); border-radius: calc(18px * var(--corner, 1)); padding: 16px 18px; }
.an-col.an-lab { background: var(--paper-ink); color: var(--paper); border: 0; } .an-col.an-lab h4 { color: var(--paper); } .an-col.an-lab p { color: var(--on-ink-soft); } .an-col.an-lab b { color: var(--amber); }
.an-col h4 { margin: 0 0 6px; } .an-col p { margin: 4px 0 0; font-size: 15px !important; }
.an-mid { font-size: 28px; color: var(--paper-muted); }
.eqs { display: grid; gap: 8px; margin-top: 16px; }
.bt-steps { list-style: none; counter-reset: b; display: grid; grid-template-columns: repeat(5, minmax(0, 1fr)); gap: 6px; margin: 0; padding: 12px 16px; border-top: 1px solid var(--line); }
.bt-steps li { counter-increment: b; font-size: 12.5px; color: var(--muted); padding: 8px 10px; border-radius: calc(10px * var(--corner, 1)); background: rgba(255, 255, 255, .04); }
.bt-steps li::before { content: counter(b) " · "; font-family: var(--font-mono); }
.bt-steps li.on { color: var(--fg); background: rgba(var(--teal-rgb), .14); }
.bt-steps li.now { color: var(--fg); box-shadow: inset 0 0 0 1.5px var(--amber); }
.mbar { display: flex; height: 26px; border-radius: calc(8px * var(--corner, 1)); overflow: hidden; background: rgba(255, 255, 255, .06); margin-top: 6px; }
.mbar i { display: flex; align-items: center; justify-content: center; font-style: normal; font-size: 11px; font-weight: 700; white-space: nowrap; overflow: hidden; transition: width .8s var(--ease); width: 0; }
#bt-used { background: var(--violet); color: #fff; } #bt-exc { background: var(--amber); color: var(--on-amber); }
.design { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: 14px; margin-top: 16px; }
.dz-pool { display: grid; gap: 8px; align-content: start; }
.dz-item { font: inherit; text-align: left; font-size: 14.5px; padding: 11px 14px; border-radius: calc(12px * var(--corner, 1)); border: 1.5px dashed rgba(var(--paper-ink-rgb),.25); background: #fff; cursor: pointer; color: var(--paper-ink); }
.dz-item:hover { border-style: solid; }
.dz-seq { list-style: none; padding: 12px; margin: 0; display: grid; gap: 8px; align-content: start; background: var(--paper-card); border: 1px solid var(--paper-line); border-radius: calc(16px * var(--corner, 1)); min-height: 120px; }
.dz-placed { display: grid; grid-template-columns: 26px 1fr; gap: 8px; align-items: start; font-size: 14.5px; padding: 8px 10px; border-radius: calc(10px * var(--corner, 1)); background: #fff; border: 1px solid var(--paper-line); }
.dz-placed b { display: inline-grid; place-items: center; width: 22px; height: 22px; border-radius: calc(6px * var(--corner, 1)); background: var(--paper-ink); color: var(--paper); font-size: 12px; }
.dz-placed.ok { border-color: var(--ok); background: var(--ok-tint-2); } .dz-placed.no { border-color: var(--crimson); background: var(--bad-tint); }
.dz-empty { color: var(--paper-muted); font-size: 14px; list-style: none; margin: 0; }
@media (max-width: 1060px) { .bt-steps { grid-template-columns: repeat(3, minmax(0, 1fr)); } }
@media (max-width: 720px) { .analogy, .design { grid-template-columns: 1fr; } .an-mid { display: none; } .bt-steps { grid-template-columns: 1fr 1fr; } }
.mbar { height: 28px !important; min-height: 28px; } .mbar i { height: 100%; flex: none; }

/* ---------- Lesson 9 components ---------- */
.cert-art { position: relative; display: grid; place-items: center; padding: 30px 0 10px; }
.cert-art .halo { position: absolute; inset: 0; background: radial-gradient(circle at 50% 50%, rgba(var(--ok-rgb), .3), transparent 60%); filter: blur(10px); z-index: -1; }
.mini-cert { width: min(280px, 80%); aspect-ratio: 1.3; border-radius: calc(16px * var(--corner, 1)); background: var(--paper); color: var(--paper-ink); padding: 18px; position: relative; box-shadow: 0 30px 60px -20px rgba(0,0,0,.6); transform: rotate(-4deg); animation: cup-bob 6s ease-in-out infinite; }
.mini-cert small { font-family: var(--font-mono); font-size: 10px; letter-spacing: .12em; text-transform: uppercase; color: var(--paper-muted); }
.mini-cert b { display: block; font-family: var(--font-display); font-size: 1.5rem; margin-top: 6px; }
.mini-cert .ln { display: block; height: 6px; border-radius: calc(3px * var(--corner, 1)); background: rgba(var(--paper-ink-rgb),.12); margin-top: 12px; width: 80%; } .mini-cert .ln.s { width: 55%; }
.mini-stamp { position: absolute; right: 16px; bottom: 14px; width: 62px; height: 62px; border-radius: 50%; border: 3px solid var(--crimson); color: var(--crimson); display: grid; place-items: center; font-family: var(--font-display); font-size: 2rem; transform: rotate(12deg); }
.road.five { grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr) auto minmax(0, 1fr) auto minmax(0, 1fr) auto minmax(0, 1fr); }
.qc-side { background: var(--paper-card); color: var(--paper-ink); border-left: 1px solid var(--line); padding: 14px; display: flex; flex-direction: column; gap: 8px; }
.qc-side .chart-lab { font-family: var(--font-mono); font-size: 11.5px; color: var(--paper-muted); }
#qc-stage .titr-wrap { grid-template-columns: minmax(0, 1.35fr) minmax(0, 0.65fr); }
.qc-log { list-style: none; margin: 0; padding: 0; display: grid; gap: 6px; }
.qc-log li { font-family: var(--font-mono); font-size: 13.5px; padding: 8px 10px; border-radius: calc(10px * var(--corner, 1)); background: #fff; border: 1px solid var(--paper-line); }
.qc-log li.good { border-color: var(--ok); background: var(--ok-tint-2); } .qc-log li.over { border-color: var(--crimson); background: var(--bad-tint); color: var(--crimson); }
.qc-log li.none { color: var(--paper-muted); font-family: inherit; }
.qc-tip { margin: auto 0 0; font-size: 13px !important; color: var(--paper-muted); }
.qc-brand { display: inline-flex; gap: 8px; align-items: center; color: var(--fg-soft); font-weight: 700; font-size: 13.5px; }
.qc-brand select { font: inherit; padding: 8px 10px; border-radius: calc(10px * var(--corner, 1)); border: 0; background: rgba(255,255,255,.1); color: var(--fg); }
.qc-brand select option { color: var(--paper-ink); }
.fine { font-size: 13.5px !important; color: var(--paper-muted); margin-top: 10px; }
.rep { margin-top: 18px; background: var(--paper-card); border: 1px solid var(--paper-line); border-radius: var(--radius); padding: 18px; }
.rep-src { display: flex; flex-wrap: wrap; gap: 8px 20px; font-weight: 700; font-size: 14.5px; }
.rep-src label { display: inline-flex; gap: 8px; align-items: center; cursor: pointer; }
.rep-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; margin-top: 14px; }
.rep-grid fieldset { border: 1px solid var(--paper-line); border-radius: calc(14px * var(--corner, 1)); padding: 10px 14px 14px; margin: 0; background: #fff; display: grid; gap: 8px; }
.rep-grid fieldset.span2 { grid-column: 1 / -1; grid-template-columns: repeat(2, minmax(0, 1fr)); }
.rep-grid legend { font-family: var(--font-mono); font-size: 11px; letter-spacing: .12em; text-transform: uppercase; color: var(--paper-muted); padding: 0 6px; }
.rep-grid label { display: flex; justify-content: space-between; align-items: center; gap: 10px; font-size: 14.5px; }
.rep-grid label span { display: inline-flex; align-items: center; gap: 6px; font-family: var(--font-mono); font-size: 12.5px; color: var(--paper-muted); white-space: nowrap; }
.rep-grid .rt-in { width: 110px; } .rt-in.wide { width: 200px !important; text-align: left; font-family: inherit; }
.rep-grid select { font: inherit; font-size: 14px; padding: 8px 10px; border-radius: calc(10px * var(--corner, 1)); border: 1.5px solid rgba(var(--paper-ink-rgb),.18); background: #fff; }
.rep-grid select.good { border-color: var(--ok); background: var(--ok-tint-2); } .rep-grid select.bad { border-color: var(--crimson); background: var(--bad-tint); }
.c-form { display: flex; flex-wrap: wrap; gap: 10px 16px; align-items: center; margin-top: 16px; font-weight: 700; font-size: 14.5px; }
.c-form label { display: inline-flex; align-items: center; gap: 8px; }
.c-ready { font-size: 14.5px !important; color: var(--paper-muted); } .c-ready.warn { color: var(--crimson); }
.cert-wrap { display: none; margin-top: 16px; }
.cert-wrap.on { display: block; animation: panel-in .6s var(--ease); }
.cert { position: relative; background: #fffdf6; color: var(--paper-ink); border-radius: calc(20px * var(--corner, 1)); padding: clamp(20px, 4vw, 40px); box-shadow: 0 30px 60px -30px rgba(var(--paper-ink-rgb),.45), inset 0 0 0 10px #fffdf6, inset 0 0 0 12px rgba(var(--paper-ink-rgb),.15); background-image: radial-gradient(circle at 100% 0, rgba(var(--amber-rgb),.12), transparent 40%), radial-gradient(circle at 0 100%, rgba(var(--ok-rgb),.10), transparent 40%); }
.ce-top { display: flex; justify-content: space-between; gap: 16px; align-items: flex-start; }
.ce-top small { font-family: var(--font-mono); font-size: 11px; letter-spacing: .14em; text-transform: uppercase; color: var(--paper-muted); }
.ce-top h3 { font-family: var(--font-display); font-size: clamp(1.6rem, 3.4vw, 2.4rem); margin: 6px 0 4px; }
.ce-sub { font-size: 13px !important; color: var(--paper-muted); margin: 0; max-width: 520px; }
.ce-seal { width: 110px; height: 110px; flex: none; }
.ce-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px 24px; margin-top: 20px; }
.ce-grid small, .ce-sign small { display: block; font-family: var(--font-mono); font-size: 10.5px; letter-spacing: .12em; text-transform: uppercase; color: var(--paper-muted); }
.ce-grid b { font-size: 17px; }
.ce-stamp { margin: 20px 0 0; display: inline-flex; flex-direction: column; align-items: flex-start; padding: 10px 18px; border: 3px solid var(--sc); color: var(--sc); border-radius: calc(12px * var(--corner, 1)); transform: rotate(-3deg); }
.ce-stamp b { font-family: var(--font-display); font-size: 1.8rem; letter-spacing: .04em; } .ce-stamp span { font-size: 13px; font-weight: 700; }
.ce-method { font-size: 14px !important; color: #4a4336; margin: 18px 0 0; line-height: 1.6; }
.ce-sign { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 14px; margin-top: 26px; }
.ce-sign span { display: block; border-bottom: 1.5px solid rgba(var(--paper-ink-rgb),.35); padding-bottom: 4px; font-family: var(--font-display); font-style: italic; font-size: 16px; min-height: 1.5em; overflow-wrap: anywhere; }
@media (max-width: 1060px) { #qc-stage .titr-wrap { grid-template-columns: 1fr; } .qc-side { border-left: 0; border-top: 1px solid var(--line); } .road.five { grid-template-columns: repeat(3, minmax(0, 1fr)); } .road.five .rd-arrow { display: none; } }
@media (max-width: 720px) { .rep-grid, .rep-grid fieldset.span2, .ce-grid { grid-template-columns: 1fr; } .ce-sign { grid-template-columns: 1fr 1fr; } .road.five { grid-template-columns: 1fr; } .rep-grid label { flex-wrap: wrap; } .ce-seal { width: 72px; height: 72px; } }
@media print {
  body.print-cert * { visibility: hidden !important; }
  body.print-cert #cert-wrap, body.print-cert #cert-wrap * { visibility: visible !important; }
  body.print-cert #cert-wrap { position: absolute; left: 0; top: 0; width: 100%; display: block !important; }
  body.print-cert .cert { box-shadow: none; }
}

/* ---------- Lesson 10 components ---------- */
.exam-art { position: relative; display: flex; gap: 18px; align-items: center; justify-content: center; padding: 34px 0 10px; }
.exam-art .halo { position: absolute; inset: 0; background: radial-gradient(circle at 50% 50%, rgba(var(--pink-rgb), .25), transparent 60%); filter: blur(10px); z-index: -1; }
.clock { width: 120px; height: 120px; border-radius: 50%; background: rgba(255,255,255,.06); box-shadow: inset 0 0 0 3px var(--amber); position: relative; display: grid; place-items: end center; padding-bottom: 18px; }
.clock i { position: absolute; left: 50%; bottom: 50%; width: 3px; background: var(--fg); border-radius: 2px; transform-origin: 50% 100%; }
.clock .h { height: 28px; transform: rotate(40deg); } .clock .m { height: 42px; background: var(--amber); animation: spin 8s linear infinite; }
@keyframes spin { to { transform: rotate(360deg); } }
.clock b { font-family: var(--font-mono); font-size: 13px; color: var(--fg-soft); }
.paper { width: 150px; aspect-ratio: .75; border-radius: calc(10px * var(--corner, 1)); background: var(--paper); color: var(--paper-ink); padding: 14px; transform: rotate(5deg); box-shadow: 0 24px 40px -20px rgba(0,0,0,.7); display: flex; flex-direction: column; gap: 8px; }
.paper small { font-family: var(--font-mono); font-size: 9.5px; letter-spacing: .1em; text-transform: uppercase; color: var(--paper-muted); }
.paper i { height: 6px; border-radius: calc(3px * var(--corner, 1)); background: rgba(var(--paper-ink-rgb),.14); } .paper i.s { width: 60%; }
.paper span { margin-top: auto; font-family: var(--font-display); font-weight: 700; color: var(--crimson); }
.mark-map { display: flex; height: 64px; border-radius: calc(16px * var(--corner, 1)); overflow: hidden; margin-top: 20px; }
.mark-map > div { width: var(--w); background: var(--c); color: var(--on-amber); display: flex; flex-direction: column; justify-content: center; padding: 0 12px; min-width: 0; }
.mark-map b { font-family: var(--font-display); font-size: 1.6rem; line-height: 1; } .mark-map span { font-size: 12px; font-weight: 700; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.tips { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 10px; margin-top: 18px; }
.tip { background: var(--paper-card); border: 1px solid var(--paper-line); border-radius: calc(14px * var(--corner, 1)); padding: 14px; }
.tip > b { display: inline-grid; place-items: center; width: 26px; height: 26px; border-radius: 50%; background: var(--paper-ink); color: var(--paper); font-size: 12.5px; }
.tip p { margin: 8px 0 0; font-size: 14px !important; color: var(--paper-muted); } .tip strong { color: var(--paper-ink); }
.chika { display: grid; gap: 14px; margin-top: 18px; }
.mk-tbl td { vertical-align: top; } .mk-tbl td:first-child b { font-family: var(--font-mono); }
.mk-tbl .mk-max { font-family: var(--font-mono); white-space: nowrap; color: var(--paper-muted); }
.mk-tbl .mk-in { white-space: nowrap; }
.mk-tbl .mk-in .rt-in.sm { width: 70px; min-width: 0; }
.mk-tbl tr.ok td { background: var(--ok-tint-2); } .mk-tbl tr.no td { background: var(--bad-tint); } .mk-tbl tr.part td { background: #fff8e6; }
.mk-why { display: block; color: var(--paper-muted); font-size: 13px; margin-top: 3px; }
.mk-award { display: inline-block; min-width: 2ch; font-family: var(--font-mono); font-weight: 700; font-size: 16px; margin-right: 6px; }
.mk-btn { font: inherit; width: 28px; height: 28px; border-radius: calc(8px * var(--corner, 1)); border: 1px solid var(--paper-line); background: #fff; cursor: pointer; margin-left: 2px; }
.exam { margin-top: 18px; }
.ex-bar { position: sticky; top: 72px; z-index: 7; display: flex; flex-wrap: wrap; gap: 10px; align-items: center; padding: 10px 14px; border-radius: calc(16px * var(--corner, 1)); background: var(--paper-ink); color: var(--paper); box-shadow: 0 14px 30px -18px rgba(0,0,0,.6); }
.ex-bar output { font-family: var(--font-mono); font-size: 26px; font-weight: 600; min-width: 5ch; color: var(--lime); }
.ex-bar output.low { color: #ff6b8a; }
.ex-bar .btn-ink { background: var(--paper); color: var(--paper-ink); }
.ex-bar .dark-ghost { color: var(--paper) !important; box-shadow: inset 0 0 0 1px rgba(var(--paper-rgb),.3) !important; }
.ex-body { position: relative; }
.ex-cover { display: none; }
.exam:not(.live) .ex-body > .stage, .exam:not(.live) .ex-body > .sheet { opacity: .35; pointer-events: none; filter: grayscale(.5); }
.exam:not(.live) .ex-cover { display: grid; place-items: center; position: absolute; inset: 0; z-index: 4; }
.ex-cover p { background: var(--paper-ink); color: var(--paper); padding: 14px 20px; border-radius: calc(14px * var(--corner, 1)); font-size: 16px !important; box-shadow: 0 20px 40px -20px rgba(0,0,0,.6); }
#ex-stage .titr-wrap { grid-template-columns: minmax(0, 1.25fr) minmax(0, 0.75fr); }
.sheet { margin-top: 18px; background: #fff; border: 1px solid var(--paper-line); border-radius: var(--radius); padding: 18px; background-image: repeating-linear-gradient(transparent 0 31px, rgba(var(--sky-rgb),.18) 31px 32px); }
.sheet h3 { margin-top: 0; }
.calc-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 10px 20px; margin-top: 16px; }
.calc-grid label { display: flex; justify-content: space-between; align-items: center; gap: 10px; font-weight: 700; font-size: 14.5px; }
.calc-grid label span { display: inline-flex; gap: 6px; align-items: center; font-family: var(--font-mono); font-size: 12.5px; color: var(--paper-muted); font-weight: 500; }
.calc-grid .rt-in { width: 110px; } .calc-grid select { font: inherit; font-size: 13.5px; padding: 8px; border-radius: calc(10px * var(--corner, 1)); border: 1.5px solid rgba(var(--paper-ink-rgb),.18); max-width: 100%; }
.calc-grid label:first-child { grid-column: 1 / -1; }
.ex-mark { display: none; margin-top: 18px; background: var(--paper-card); border: 1px solid var(--paper-line); border-radius: var(--radius); padding: 18px; }
.ex-mark.on { display: block; animation: panel-in .6s var(--ease); }
.ex-mark-top { display: flex; justify-content: space-between; align-items: center; gap: 10px; }
.ex-mark-top h3 { margin: 0; } .ex-mark-top output { font-family: var(--font-display); font-size: 2.4rem; font-weight: 700; color: var(--crimson); }
.lookback { display: grid; gap: 10px; margin-top: 18px; }
.lb-q { background: var(--paper-card); border: 1px solid var(--paper-line); border-radius: calc(16px * var(--corner, 1)); padding: 14px 16px; display: grid; gap: 10px; }
.lb-q p { margin: 0; font-family: var(--font-display); font-size: 1.15rem !important; }
.lb-btns { display: flex; flex-wrap: wrap; gap: 8px; }
.lb-btns button { font: inherit; font-size: 13.5px; font-weight: 700; padding: 7px 12px; border-radius: 999px; border: 1.5px solid rgba(var(--paper-ink-rgb),.18); background: #fff; cursor: pointer; }
.lb-btns [data-s="yes"][aria-pressed="true"] { background: var(--ok); border-color: var(--ok); color: #fff; }
.lb-btns [data-s="part"][aria-pressed="true"] { background: var(--amber); border-color: var(--amber); }
.lb-btns [data-s="not"][aria-pressed="true"] { background: var(--crimson); border-color: var(--crimson); color: #fff; }
.lb-empty { color: var(--paper-muted); }
.lb-add { display: flex; gap: 8px; margin-top: 12px; } .lb-add input { flex: 1; font: inherit; padding: 10px 12px; border-radius: calc(12px * var(--corner, 1)); border: 1.5px solid rgba(var(--paper-ink-rgb),.18); min-width: 0; }
.growth { display: grid; gap: 8px; margin-top: 18px; }
.gm-row { display: grid; grid-template-columns: 34px minmax(0, 1.3fr) minmax(0, 1fr) auto; gap: 12px; align-items: center; padding: 10px 14px; border-radius: calc(14px * var(--corner, 1)); background: var(--paper-card); border: 1px solid var(--paper-line); color: var(--paper-ink); text-decoration: none; }
.gm-row:hover { border-color: var(--paper-ink); }
.gm-row > b { font-family: var(--font-mono); color: var(--paper-muted); }
.gm-name { font-weight: 700; font-size: 14.5px; }
.gm-bar { height: 10px; border-radius: calc(99px * var(--corner, 1)); background: rgba(var(--paper-ink-rgb),.08); overflow: hidden; } .gm-bar i { display: block; height: 100%; background: linear-gradient(90deg, var(--amber), var(--ok)); }
.gm-meta { font-family: var(--font-mono); font-size: 12px; color: var(--paper-muted); white-space: nowrap; }
.ready { list-style: none; padding: 0; margin: 16px 0 0; display: grid; gap: 8px; }
.ready label { display: grid; grid-template-columns: 22px 1fr; gap: 10px; align-items: start; padding: 10px 14px; border-radius: calc(12px * var(--corner, 1)); background: var(--paper-card); border: 1px solid var(--paper-line); cursor: pointer; font-size: 15px; }
.ready input { margin-top: 4px; accent-color: var(--ok); width: 18px; height: 18px; }
.ready-n { font-family: var(--font-mono); font-size: 1rem; color: var(--paper-muted); font-weight: 500; }
.unit-done { display: none; margin-top: 18px; padding: 22px 24px; border-radius: var(--radius-lg); background: linear-gradient(135deg, var(--paper-ink), #2a3660); color: var(--paper); text-align: center; }
.unit-done.on { display: block; animation: panel-in .7s var(--ease); }
.unit-done b { font-family: var(--font-display); font-size: 2rem; } .unit-done p { color: var(--on-ink-soft); max-width: 560px; margin: 8px auto 14px; }
.unit-done .btn-ink { background: var(--amber); color: var(--on-amber); }
@media (max-width: 1060px) { #ex-stage .titr-wrap { grid-template-columns: 1fr; } .tips { grid-template-columns: repeat(2, minmax(0, 1fr)); } .ex-bar { top: 112px; } }
@media (max-width: 720px) { .tips, .calc-grid { grid-template-columns: 1fr; } .gm-row { grid-template-columns: 30px minmax(0, 1fr); } .gm-bar, .gm-meta { grid-column: 2; } .mark-map span { display: none; } .exam-art .paper { display: none; } .mk-tbl { min-width: 560px; } }
.ex-mark-top output { white-space: nowrap; } @media (max-width: 720px) { .ex-mark-top output { font-size: 1.8rem; } }


/* =========================================================
   Modern V2 Lesson Components (Lessons 03, 04, 05)
   ========================================================= */

/* Hero Diagram Artwork */
.pend-hero-art {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 18px;
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: var(--radius-lg);
  backdrop-filter: blur(10px);
}
.pend-hero-svg {
  width: 100%;
  max-width: 320px;
  height: auto;
  display: block;
}
@media (max-width: 860px) {
  .pend-hero-art { display: none; }
}

/* Active Movement Break */
aside.l-sec {
  border-radius: var(--radius-lg);
  padding: 24px 28px;
  margin-top: 32px;
  margin-bottom: 32px;
  border-width: 1px;
  border-style: solid;
}

/* 3D Story Stage */
.story-wrap {
  position: relative;
  margin-top: 24px;
  background: radial-gradient(70% 70% at 50% 30%, #16203a, var(--ink-950));
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: 0 24px 60px -20px rgba(0, 0, 0, 0.65);
}
.story-wrap canvas {
  width: 100% !important;
  height: clamp(340px, 48vw, 460px) !important;
  display: block;
}
.story-overlay {
  position: absolute;
  top: 14px;
  left: 14px;
  right: 14px;
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  pointer-events: none;
  z-index: 3;
}
.story-badge {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--amber);
  background: rgba(var(--ink-900-rgb), 0.88);
  border: 1px solid rgba(var(--amber-rgb), 0.35);
  padding: 5px 12px;
  border-radius: 999px;
  backdrop-filter: blur(8px);
}
.story-bubbles {
  display: flex;
  flex-direction: column;
  gap: 8px;
  max-width: 260px;
}
.story-caption {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 16px 20px;
  background: rgba(var(--ink-950-rgb), 0.92);
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  backdrop-filter: blur(12px);
}
.story-caption-text { flex: 1 1 240px; }
.story-caption-text strong {
  display: block;
  font-size: 14.5px;
  font-weight: 700;
  color: var(--fg);
  line-height: 1.35;
}
.story-caption-text p {
  margin: 4px 0 0 !important;
  font-size: 13px !important;
  color: var(--fg-soft) !important;
  line-height: 1.4 !important;
}
.story-controls {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
}
.story-dots {
  display: flex;
  align-items: center;
  gap: 6px;
}
.story-dots button {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  border: 0;
  background: rgba(255, 255, 255, 0.25);
  cursor: pointer;
  padding: 0;
  transition: all 0.25s;
}
.story-dots button.on {
  background: var(--amber);
  transform: scale(1.3);
  box-shadow: 0 0 8px var(--amber);
}

/* Sort Board */
.sort-board {
  margin-top: 24px;
  background: var(--ink-900);
  color: var(--fg);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-lg);
  padding: clamp(18px, 3vw, 28px);
  box-shadow: 0 20px 50px -15px rgba(0, 0, 0, 0.5);
}
.sort-tray-label {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-bottom: 12px;
}
.sort-bins {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
  margin-top: 18px;
}
@media (max-width: 720px) {
  .sort-bins { grid-template-columns: 1fr; }
}
.sort-bins .bin {
  border-radius: calc(16px * var(--corner, 1));
  padding: 16px;
  min-height: 140px;
  border: 2px dashed rgba(255, 255, 255, 0.18);
  background: rgba(255, 255, 255, 0.02);
  transition: all 0.25s var(--ease);
  cursor: pointer;
}
.sort-bins .bin:hover, .sort-bins .bin.ready {
  border-color: var(--teal);
  background: rgba(var(--teal-rgb), 0.06);
}
.sort-bins .bin.over {
  border-color: var(--amber);
  background: rgba(var(--amber-rgb), 0.12);
  transform: scale(1.02);
}
.sort-bins .bin h4 {
  margin: 0 0 6px;
  font-size: 14.5px;
  font-weight: 700;
  display: flex;
  align-items: center;
  gap: 8px;
  color: var(--fg);
}
.sort-bins .bin h4 .dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  display: inline-block;
  flex: none;
}
.sort-bins .bin small {
  display: block;
  color: var(--muted);
  font-size: 11.5px;
  font-family: var(--font-mono);
  line-height: 1.4;
}
.sort-bins .bin .drop {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 12px;
  min-height: 36px;
}
.sort-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-top: 20px;
  padding-top: 14px;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
}

/* 3D Practical Bench */
.bench {
  position: relative;
  margin-top: 24px;
  background: radial-gradient(75% 75% at 50% 30%, #151e36, var(--ink-950));
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: 0 24px 60px -20px rgba(0, 0, 0, 0.7);
  color: var(--fg);
}
.bench-stage {
  position: relative;
  width: 100%;
  height: clamp(340px, 48vw, 460px);
  background: radial-gradient(circle at 50% 40%, rgba(var(--teal-rgb), 0.08), transparent 70%);
}
.bench-stage canvas {
  width: 100% !important;
  height: 100% !important;
  display: block;
}
.bench-overlay-top {
  position: absolute;
  top: 14px;
  left: 14px;
  right: 14px;
  pointer-events: none;
  z-index: 3;
}
.bench-chip {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 11.5px;
  color: var(--fg);
  background: rgba(var(--ink-900-rgb), 0.88);
  border: 1px solid rgba(var(--teal-rgb), 0.3);
  padding: 6px 14px;
  border-radius: 999px;
  backdrop-filter: blur(10px);
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.4);
}
.bench-panel {
  padding: 18px 20px;
  background: rgba(var(--ink-900-rgb), 0.92);
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(14px);
}
.ctl-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px 18px;
}
@media (max-width: 640px) {
  .ctl-grid { grid-template-columns: 1fr; }
}
.ctl { display: flex; flex-direction: column; gap: 6px; }
.ctl label {
  font-size: 12.5px;
  font-weight: 600;
  color: var(--fg-soft);
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.ctl label strong {
  font-family: var(--font-mono);
  color: var(--amber);
  font-size: 12.5px;
}
.ctl input[type="range"] {
  width: 100%;
  accent-color: var(--amber);
  cursor: pointer;
  height: 6px;
  border-radius: calc(3px * var(--corner, 1));
}
.ctl select {
  width: 100%;
  padding: 10px 12px;
  border-radius: calc(10px * var(--corner, 1));
  background: #0f172a;
  color: #f8fafc;
  border: 1px solid rgba(255, 255, 255, 0.16);
  font-family: var(--font-body);
  font-size: 13.5px;
  font-weight: 600;
}
.readout-bar {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 10px;
  margin-top: 18px;
  padding-top: 16px;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
}
@media (max-width: 860px) {
  .readout-bar { grid-template-columns: repeat(3, minmax(0, 1fr)); }
}
@media (max-width: 540px) {
  .readout-bar { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
.ro {
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: calc(12px * var(--corner, 1));
  padding: 10px 12px;
  display: flex;
  flex-direction: column;
  gap: 3px;
}
.ro small {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
}
.ro strong {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  color: var(--teal);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.bench-btns {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-top: 16px;
}

/* Lab Results Table */
.table-wrap {
  margin-top: 24px;
  background: var(--paper-card);
  border: 1px solid var(--paper-line);
  border-radius: var(--radius-lg);
  padding: clamp(16px, 2.5vw, 24px);
  box-shadow: 0 10px 30px rgba(var(--paper-ink-rgb), 0.05);
}
.table-head {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 16px;
}
.table-head h3 {
  margin: 0;
  font-size: 1.15rem;
  color: var(--paper-ink);
}
.table-actions {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}
.table-scroll {
  overflow-x: auto;
  border-radius: calc(12px * var(--corner, 1));
  border: 1px solid var(--paper-line);
  background: #fff;
}
.lab-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
  min-width: 580px;
}
.lab-table th, .lab-table td {
  padding: 12px 14px;
  text-align: left;
  border-bottom: 1px solid var(--paper-line);
  vertical-align: middle;
}
.lab-table th {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--paper-muted);
  background: rgba(var(--paper-ink-rgb), 0.03);
  font-weight: 600;
}
.lab-table tr:last-child td { border-bottom: 0; }
.lab-table select {
  font: inherit;
  font-size: 13.5px;
  padding: 7px 10px;
  border-radius: calc(8px * var(--corner, 1));
  border: 1.5px solid rgba(var(--paper-ink-rgb), 0.16);
  background: #fff;
  color: var(--paper-ink);
  max-width: 100%;
}
.lab-table select.right {
  border-color: var(--ok) !important;
  background: rgba(var(--ok-rgb), 0.1) !important;
  color: var(--ok) !important;
}
.lab-table select.wrong {
  border-color: var(--crimson) !important;
  background: rgba(var(--crimson-rgb), 0.1) !important;
  color: var(--crimson) !important;
}
.lab-table td.ok { background: rgba(var(--ok-rgb), 0.1); }
.lab-table td.no { background: rgba(var(--crimson-rgb), 0.08); }
.swatch {
  display: inline-block;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  margin-right: 6px;
  vertical-align: middle;
}

/* Concept Cards */
.concept-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
  margin-top: 20px;
}
@media (max-width: 680px) {
  .concept-grid { grid-template-columns: 1fr; }
}
.concept-card {
  background: var(--paper-card);
  border: 1px solid var(--paper-line);
  border-radius: var(--radius);
  padding: 20px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  box-shadow: 0 4px 14px rgba(var(--paper-ink-rgb), 0.04);
  transition: transform 0.2s, border-color 0.2s;
}
.concept-card:hover {
  transform: translateY(-2px);
  border-color: rgba(var(--crimson-rgb), 0.3);
}
.concept-card .tag {
  align-self: flex-start;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  padding: 4px 10px;
  border-radius: 999px;
  background: rgba(var(--paper-ink-rgb), 0.06);
  color: var(--paper-ink);
  font-weight: 700;
}
.concept-card h3 {
  margin: 4px 0 0;
  font-family: var(--font-display);
  font-size: 1.2rem;
  color: var(--paper-ink);
  line-height: 1.3;
}
.concept-card p {
  margin: 4px 0 0;
  font-size: 14px;
  color: var(--paper-muted);
  line-height: 1.55;
}
.concept-card code {
  font-family: var(--font-mono);
  font-size: 12.5px;
  color: var(--paper-ink);
  background: rgba(var(--paper-ink-rgb), 0.07);
  padding: 2px 6px;
  border-radius: calc(4px * var(--corner, 1));
}

/* Concept Zoom Stage */
.zoom-box {
  margin-top: 24px;
  background: radial-gradient(75% 75% at 50% 30%, #171d34, var(--ink-950));
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: 0 24px 60px -20px rgba(0, 0, 0, 0.7);
  color: var(--fg);
}
.zoom-stage {
  position: relative;
  width: 100%;
  height: clamp(340px, 48vw, 460px);
}
.zoom-stage canvas {
  width: 100% !important;
  height: 100% !important;
  display: block;
}
.zoom-status {
  position: absolute;
  top: 14px;
  left: 14px;
  right: 14px;
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 11.5px;
  color: var(--fg);
  background: rgba(var(--ink-900-rgb), 0.88);
  border: 1px solid rgba(var(--teal-rgb), 0.35);
  padding: 6px 14px;
  border-radius: 999px;
  backdrop-filter: blur(10px);
  width: max-content;
  max-width: calc(100% - 28px);
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.4);
}
.zoom-bar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding: 14px 18px;
  background: rgba(var(--ink-950-rgb), 0.85);
  border-top: 1px solid rgba(255, 255, 255, 0.08);
}
.zoom-bar .pill {
  padding: 8px 14px;
  border-radius: 999px;
  border: 1px solid rgba(255, 255, 255, 0.12);
  background: rgba(255, 255, 255, 0.05);
  color: var(--fg-soft);
  font-family: var(--font-body);
  font-size: 12.5px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
}
.zoom-bar .pill:hover {
  background: rgba(255, 255, 255, 0.1);
  color: var(--fg);
}
.zoom-bar .pill.on, .zoom-bar .pill[aria-pressed="true"] {
  background: var(--teal);
  color: #041311;
  border-color: var(--teal);
  font-weight: 700;
  box-shadow: 0 0 14px rgba(var(--teal-rgb), 0.3);
}

/* Worked Examples List */
.ex-list {
  display: grid;
  gap: 16px;
  margin-top: 20px;
}
.ex-card {
  background: var(--paper-card);
  border: 1px solid var(--paper-line);
  border-radius: var(--radius);
  overflow: hidden;
  transition: border-color 0.2s, box-shadow 0.2s;
}
.ex-card[open] {
  border-color: rgba(var(--paper-ink-rgb), 0.25);
  box-shadow: 0 6px 20px rgba(var(--paper-ink-rgb), 0.06);
}
.ex-card summary {
  list-style: none;
  cursor: pointer;
  padding: 16px 20px;
  display: flex;
  align-items: center;
  gap: 14px;
  font-size: 15px;
  color: var(--paper-ink);
  background: rgba(var(--paper-ink-rgb), 0.02);
  user-select: none;
}
.ex-card summary::-webkit-details-marker { display: none; }
.ex-card summary .ex-num {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  color: #fff;
  background: var(--crimson);
  width: 28px;
  height: 28px;
  border-radius: calc(8px * var(--corner, 1));
  display: grid;
  place-items: center;
  flex: none;
}
.ex-card summary em {
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 12.5px;
  font-style: normal;
  color: var(--teal);
  background: rgba(var(--ok-rgb), 0.1);
  padding: 4px 10px;
  border-radius: calc(6px * var(--corner, 1));
  font-weight: 600;
  white-space: nowrap;
}
.ex-card .ex-body {
  padding: 18px 22px;
  border-top: 1px dashed var(--paper-line);
  font-size: 14.5px;
  line-height: 1.6;
}
.ex-card .ex-body p { margin: 6px 0; }
.ex-card .steps {
  list-style: none;
  padding: 0;
  margin: 12px 0 0;
  counter-reset: step-counter;
  display: grid;
  gap: 10px;
}
.ex-card .steps li {
  counter-increment: step-counter;
  position: relative;
  padding-left: 36px;
  font-size: 14px;
  line-height: 1.55;
  color: var(--paper-ink);
}
.ex-card .steps li::before {
  content: counter(step-counter);
  position: absolute;
  left: 0;
  top: 1px;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: rgba(var(--paper-ink-rgb), 0.08);
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  display: grid;
  place-items: center;
  color: var(--paper-ink);
}

/* Bridge Challenge & Vinegar Box */
.vinegar-box {
  margin-top: 24px;
  background: var(--ink-900);
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: var(--radius-lg);
  padding: clamp(20px, 3vw, 32px);
  color: var(--fg);
  box-shadow: 0 20px 50px -15px rgba(0, 0, 0, 0.6);
}
.clock-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  padding: 16px;
  border-radius: calc(16px * var(--corner, 1));
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid rgba(255, 255, 255, 0.08);
}
.clock-well {
  display: flex;
  justify-content: center;
  align-items: center;
  margin-bottom: 12px;
}
.pill-row {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 10px;
  margin-top: 10px;
}
.pill-row .pill {
  padding: 9px 16px;
  border-radius: 999px;
  border: 1.5px solid rgba(255, 255, 255, 0.16);
  background: rgba(255, 255, 255, 0.06);
  color: var(--fg);
  font-family: var(--font-mono);
  font-size: 13.5px;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.2s var(--ease);
}
.pill-row .pill:hover {
  background: rgba(255, 255, 255, 0.12);
  border-color: rgba(255, 255, 255, 0.3);
}
.pill-row .pill.on {
  background: var(--teal);
  color: #041311;
  border-color: var(--teal);
  box-shadow: 0 0 16px rgba(var(--teal-rgb), 0.4);
}

/* Dynamic Feedback Containers */
.feedback {
  margin-top: 16px;
  padding: 14px 18px;
  border-radius: calc(12px * var(--corner, 1));
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.1);
  display: none;
  font-size: 14px;
  line-height: 1.55;
  color: var(--fg-soft);
}
.feedback.on {
  display: block;
  animation: panel-in 0.3s var(--ease);
}
.feedback strong { color: var(--fg); }
.feedback code {
  font-family: var(--font-mono);
  background: rgba(255, 255, 255, 0.1);
  padding: 2px 6px;
  border-radius: calc(4px * var(--corner, 1));
  color: var(--teal);
}
.table-wrap .feedback {
  background: rgba(var(--paper-ink-rgb), 0.04);
  border: 1px solid var(--paper-line);
  color: var(--paper-ink);
}
.table-wrap .feedback strong { color: var(--paper-ink); }
.table-wrap .feedback code {
  background: rgba(var(--paper-ink-rgb), 0.08);
  color: var(--paper-ink);
}

/* Assignment List */
.assign-list {
  display: grid;
  gap: 20px;
  margin-top: 24px;
}
.assign-card {
  background: var(--paper-card);
  border: 1px solid var(--paper-line);
  border-radius: var(--radius);
  padding: 22px;
  box-shadow: 0 4px 16px rgba(var(--paper-ink-rgb), 0.05);
}
.assign-card .assign-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 12px;
}
.assign-card .assign-head h3,
.assign-card .assign-head h4 {
  margin: 0;
  font-size: 1.15rem;
  color: var(--paper-ink);
}
.assign-mark {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  color: var(--crimson);
  background: rgba(var(--crimson-rgb), 0.1);
  padding: 3px 9px;
  border-radius: 999px;
  white-space: nowrap;
}
.assign-input {
  width: 100%;
  min-height: 90px;
  padding: 12px 14px;
  border-radius: calc(12px * var(--corner, 1));
  border: 1.5px solid rgba(var(--paper-ink-rgb), 0.16);
  background: #fff;
  color: var(--paper-ink);
  font: inherit;
  font-size: 14px;
  margin-top: 14px;
  resize: vertical;
  box-sizing: border-box;
}
.assign-input:focus {
  outline: none;
  border-color: var(--crimson);
  box-shadow: 0 0 0 4px rgba(var(--crimson-rgb), 0.12);
}
.assign-actions {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-top: 12px;
  flex-wrap: wrap;
}
.assign-hint {
  font-size: 12.5px;
  color: var(--paper-muted);
}
.assign-solution {
  margin-top: 16px;
  padding: 16px 18px;
  border-radius: calc(14px * var(--corner, 1));
  background: var(--ok-tint-2);
  border: 1px solid rgba(var(--ok-rgb), 0.3);
  font-size: 14px;
  line-height: 1.6;
  color: var(--paper-ink);
}
.assign-solution[hidden] {
  display: none !important;
}
.assign-solution h4,
.assign-solution h5 {
  margin: 0 0 8px;
  font-size: 14.5px;
  color: var(--ok);
}
.assign-solution ul {
  margin: 0;
  padding-left: 20px;
}
.assign-solution li {
  margin-bottom: 8px;
}

/* Next Lesson CTA */
.next-lesson-cta {
  margin-top: 36px;
  padding: 26px 28px;
  border-radius: var(--radius-lg);
  background: linear-gradient(135deg, rgba(var(--teal-rgb), 0.14), rgba(var(--amber-rgb), 0.12));
  border: 1px solid var(--line-strong);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}
.next-lesson-cta .eyebrow {
  display: block;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--amber);
  margin-bottom: 4px;
}
.next-lesson-cta h3 {
  margin: 0;
  font-size: 1.25rem;
  color: var(--fg);
}
.next-lesson-cta p {
  margin: 4px 0 0;
  font-size: 14px;
  color: var(--fg-soft);
}
.next-lesson-cta .btn {
  margin: 0;
}

/* =====================================================================
   Lessons 3–5 · study-readability pass
   (classes below are only used by lessons 3–5, or scoped to them)
   ===================================================================== */

/* Stop Manrope turning "(c)" into "©" and similar ligature surprises */
body.lesson-page { font-variant-ligatures: no-common-ligatures no-contextual; }

/* ---------- Concept cards: explanation → formula → when to use → trap ---------- */
.concept-grid { gap: 18px; margin-top: 24px; }
.concept-card { padding: 22px 22px 20px; gap: 10px; }
.concept-card:hover { transform: none; }
.concept-card .tag { background: color-mix(in srgb, var(--c, #888) 16%, transparent); color: var(--paper-ink); }
.concept-card h3 { font-size: 1.32rem; margin-top: 2px; }
.concept-card p { font-size: 15.5px; line-height: 1.6; color: var(--paper-text); margin: 0; }
.concept-card .fx {
  font-family: var(--font-mono); font-size: 15px; line-height: 1.5;
  background: var(--paper-ink); color: var(--paper);
  border-radius: calc(10px * var(--corner, 1)); padding: 11px 14px; margin: 2px 0 0;
  overflow-x: auto; white-space: nowrap;
}
.concept-card .fx .lbl {
  display: inline-block; min-width: 0; margin-right: 10px;
  font-size: 10.5px; letter-spacing: .08em; text-transform: uppercase; color: #b7ac98;
}
.concept-card .fx .arr { color: var(--amber); padding: 0 6px; }
.concept-card .fx + .fx { margin-top: -2px; }
.concept-card .use, .concept-card .trap, .concept-card .eg {
  font-size: 14.5px; padding: 10px 12px; border-radius: calc(10px * var(--corner, 1)); line-height: 1.5;
}
.concept-card .use  { background: rgba(var(--ok-rgb), .09); border-left: 3px solid var(--ok); }
.concept-card .eg   { background: rgba(var(--info-rgb), .07); border-left: 3px solid var(--info); }
.concept-card .trap { background: rgba(var(--crimson-rgb), .07); border-left: 3px solid var(--crimson); }
.concept-card .use b, .concept-card .trap b, .concept-card .eg b {
  display: block; font-size: 11px; letter-spacing: .08em; text-transform: uppercase; margin-bottom: 2px;
}
.concept-card .use b { color: var(--ok-deep); }
.concept-card .eg b { color: #2f56c9; }
.concept-card .trap b { color: var(--crimson); }
.concept-card ol { margin: 0; padding-left: 20px; font-size: 15px; line-height: 1.6; color: var(--paper-text); }
.concept-card ol li + li { margin-top: 4px; }
.concept-card code { font-size: 13.5px; }
.study-summary { margin-top: 30px; }
.study-summary h3 { margin: 0 0 4px; }
.study-summary > p { margin: 0; color: var(--paper-muted); font-size: 15px; }
.study-summary .tbl td:first-child { font-weight: 700; white-space: nowrap; }
.study-summary .tbl td { font-size: 14.5px; line-height: 1.5; }

/* ---------- Explorer: tap cards instead of an overlapping pin track ---------- */
body:is([data-lesson="l03"],[data-lesson="l04"],[data-lesson="l05"]) .ph-explorer h3 { color: #fff; margin: 0 0 4px; }
body:is([data-lesson="l03"],[data-lesson="l04"],[data-lesson="l05"]) .ph-explorer .ph-sub { color: var(--fg-soft); font-size: 14.5px; margin: 0 0 16px; }
.ph-choices { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 10px; }
@media (max-width: 860px) { .ph-choices { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
.ph-choice {
  text-align: left; cursor: pointer; font: inherit; color: var(--fg-soft);
  background: rgba(255, 255, 255, .04); border: 1.5px solid rgba(255, 255, 255, .1);
  border-radius: calc(14px * var(--corner, 1)); padding: 12px 14px; display: flex; flex-direction: column; gap: 4px;
  transition: border-color .2s, background .2s, transform .2s;
}
.ph-choice:hover { background: rgba(255, 255, 255, .08); }
.ph-choice.on { border-color: var(--pcol, var(--teal)); background: rgba(255, 255, 255, .09); transform: translateY(-2px); }
.ph-choice .k { font-family: var(--font-mono); font-size: 15px; font-weight: 700; color: var(--pcol, var(--teal)); }
.ph-choice .n { font-size: 13px; line-height: 1.35; }
.ph-detail {
  margin-top: 14px; padding: 16px 18px; border-radius: calc(14px * var(--corner, 1));
  background: rgba(255, 255, 255, .05); border: 1px solid rgba(255, 255, 255, .1);
  display: grid; grid-template-columns: minmax(0, 1fr); gap: 6px;
}
.ph-detail .num { font-family: var(--font-mono); font-size: 22px; font-weight: 700; line-height: 1.2; }
.ph-detail .num small { display: block; font-family: var(--font-body); font-size: 14px; font-weight: 600; color: #fff; margin-top: 4px; }
.ph-detail p { font-size: 15px !important; line-height: 1.6; color: #d6deee !important; margin: 2px 0 0 !important; }

/* ---------- Sort bins: title on its own line, hint below, readable ---------- */
.sort-bins .bin h4 { flex-wrap: wrap; font-size: 15px; line-height: 1.3; }
.sort-bins .bin h4 small { flex-basis: 100%; font-size: 12px; margin-top: 4px; color: #aab4c8; }
.sort-board .sort-item { font-size: 14px; }

/* ---------- 3D bench readouts: never truncate a value ---------- */
.ro strong { white-space: normal; overflow: visible; text-overflow: clip; font-size: 14px; line-height: 1.35; }
.ro small { font-size: 10.5px; }
.ctl label { font-size: 13.5px; gap: 8px; }
.ctl label strong { font-size: 13.5px; white-space: nowrap; }
.bench-btns { flex-wrap: wrap; }
.bench-chip { font-size: 12.5px; white-space: normal; max-width: 100%; }

/* ---------- Lab notebook (cream card): visible buttons, readable givens/hints ---------- */
.table-wrap .btn-ghost { color: var(--paper-ink); background: #fff; box-shadow: inset 0 0 0 1.5px rgba(var(--paper-ink-rgb), .22); }
.table-wrap .btn-ghost:hover { background: rgba(var(--paper-ink-rgb), .05); }
.table-wrap .sort-score { color: var(--paper-ink); font-weight: 700; }
.lab-table { font-size: 14.5px; }
.lab-table th { font-size: 11.5px; line-height: 1.35; vertical-align: bottom; }
.lab-table td .given { display: block; margin-top: 4px; font-size: 13px; color: var(--paper-muted); }
.lab-table td .given b { color: var(--paper-ink); font-weight: 600; }
.lab-table td.hint { font-family: var(--font-mono); font-size: 13px; color: var(--ok-deep); font-weight: 600; }

/* ---------- Worked examples: each calculation on its own readable line ---------- */
.ex-card summary { font-size: 15.5px; line-height: 1.4; }
.ex-card .ex-body { font-size: 16px; line-height: 1.65; padding: 20px 24px 22px; }
.ex-card .ex-body > p code { font-family: inherit; font-size: inherit; font-weight: 700; background: none; padding: 0; color: var(--paper-ink); }
.ex-card .steps { gap: 14px; margin-top: 16px; }
.ex-card .steps li { font-size: 15.5px; line-height: 1.6; padding-left: 38px; }
.ex-card .steps li::before { width: 26px; height: 26px; font-size: 12px; background: var(--crimson); color: #fff; }
.ex-card .steps li code {
  display: block; width: fit-content; max-width: 100%; overflow-x: auto;
  margin: 6px 0 2px; padding: 9px 13px; border-radius: calc(9px * var(--corner, 1));
  font-family: var(--font-mono); font-size: 14.5px; line-height: 1.5;
  background: var(--paper-ink); color: var(--paper); white-space: nowrap;
}
.ex-card .steps li code + br { display: none; }

/* ---------- Active break: readable label on the pale card ---------- */
#movement-break .phase { color: #3f6b0a; }
#movement-break .intro { color: var(--paper-text); }

/* ---------- Bridge challenge ---------- */
.vinegar-box .clock-card p { font-size: 15px !important; line-height: 1.6; }
.vinegar-box .clock-card p code { font-family: inherit; background: none; padding: 0; color: #fff; font-weight: 700; }
.vinegar-box .feedback { font-size: 15px; }

/* ---------- Hero diagrams ---------- */
body:is([data-lesson="l03"],[data-lesson="l04"],[data-lesson="l05"]) .pend-hero-art { height: auto; min-height: 280px; padding: 18px; }
body:is([data-lesson="l03"],[data-lesson="l04"],[data-lesson="l05"]) .pend-hero-svg { max-width: 420px; height: auto; }
.ex-card .steps li code.inl { display: inline; margin: 0; padding: 1px 6px; font-size: .92em; background: rgba(var(--paper-ink-rgb), .08); color: var(--paper-ink); white-space: nowrap; }
/* uppercase turns η into "H" and R_eq into "REQ" — keep these labels in normal case */
.lab-table th, .ro small { text-transform: none; letter-spacing: .02em; }
.lab-table th { font-size: 12.5px; }
/* bridge challenge: emphasis was dark-on-dark; decorative dot overlapped the label */
.vinegar-box strong, .vinegar-box .feedback strong { color: #fff; }
.vinegar-box #v-drop { display: none; }
/* bench control labels: keep "R<sub>g</sub>:" together, value on the right */
.ctl label { display: block; }
.ctl label strong { float: right; margin-left: 8px; }
/* phones: revision tables fit the screen; notebook names get a readable column */
@media (max-width: 640px) {
  .study-summary .tbl { min-width: 0; }
  .study-summary .tbl th, .study-summary .tbl td { padding: 10px 9px; font-size: 13.5px; }
  .study-summary .tbl td:first-child { white-space: normal; }
}
.lab-table td:first-child { min-width: 230px; }

/* ---------- "What the symbols mean" key (lessons 3–5) ---------- */
.symbol-key { margin-top: 22px; background: var(--paper-card); border: 1px solid var(--paper-line); border-left: 4px solid var(--info); border-radius: var(--radius); padding: 16px 20px; }
.symbol-key h4 { margin: 0 0 10px; font-size: 15px; letter-spacing: .02em; color: var(--paper-ink); }
.symbol-key dl { margin: 0; display: grid; grid-template-columns: repeat(auto-fill, minmax(250px, 1fr)); gap: 8px 22px; }
.symbol-key dl > div { display: grid; grid-template-columns: 74px 1fr; gap: 10px; align-items: baseline; }
.symbol-key dt { font-family: Georgia, "Times New Roman", serif; font-size: 18px; font-weight: 700; color: var(--paper-ink); white-space: nowrap; }
.symbol-key dd { margin: 0; font-size: 14.5px; line-height: 1.45; color: var(--paper-text); }
/* real subscripts everywhere: small and low, never stretching the line */
body:is([data-lesson="l03"],[data-lesson="l04"],[data-lesson="l05"]) sub { font-size: .72em; line-height: 0; vertical-align: -0.28em; }

/* =========================================================
   v3 UI pass — live graph cards, phone-friendly tables,
   wrapping equations, 3D stage zoom controls
   ========================================================= */
/* Graph card that sits under a 3D bench / zoom */
.graph-card { margin-top: 18px; background: #fffdf8; border: 1px solid var(--paper-line); border-radius: var(--radius); padding: 16px 14px 14px; box-shadow: 0 14px 34px -24px rgba(var(--paper-ink-rgb), .35); }
.graph-card .gc-head { display: flex; align-items: flex-start; justify-content: space-between; gap: 10px; margin-bottom: 8px; }
.graph-card .gc-kicker { font-family: var(--font-mono); font-size: 10.5px; letter-spacing: .12em; text-transform: uppercase; color: var(--paper-muted); display: block; }
.graph-card h4 { font-family: var(--font-display); font-size: 1.12rem; line-height: 1.2; margin: 2px 0 0; color: var(--paper-ink); }
.graph-card .gc-badge { flex: none; font-family: var(--font-mono); font-size: 11px; padding: 4px 9px; border-radius: 999px; background: rgba(var(--ok-rgb), .12); color: #0b7a63; white-space: nowrap; }
.graph-card .gc-badge.wait { background: rgba(var(--paper-ink-rgb), .06); color: var(--paper-muted); }
.graph-card .gc-note { font-size: 13.5px; line-height: 1.55; color: var(--paper-muted); margin: 10px 0 0; }
.graph-card .gc-note b, .graph-card .gc-note strong { color: var(--paper-ink); }
.graph-card .gc-tabs { display: flex; flex-wrap: wrap; gap: 6px; margin: 4px 0 8px; }
.graph-card .gc-tabs button { font: 600 12.5px var(--font-body); padding: 7px 12px; min-height: 36px; border-radius: 999px; border: 1.5px solid var(--paper-line); background: #fff; color: var(--paper-ink); cursor: pointer; }
.graph-card .gc-tabs button[aria-pressed="true"] { background: var(--paper-ink); color: var(--paper); border-color: var(--paper-ink); }
.graph-card .gc-stats { display: grid; grid-template-columns: repeat(auto-fit, minmax(96px, 1fr)); gap: 6px; margin-top: 10px; }
.graph-card .gc-stat { background: rgba(var(--paper-ink-rgb), .04); border-radius: calc(10px * var(--corner, 1)); padding: 7px 9px; }
.graph-card .gc-stat span { display: block; font-family: var(--font-mono); font-size: 10.5px; letter-spacing: .02em; color: var(--paper-muted); }
.graph-card .gc-stat b { font-family: var(--font-mono); font-size: 14px; color: var(--paper-ink); }
.stage .graph-card { margin: 0 14px 14px; background: rgba(255, 255, 255, .03); border-color: var(--line); box-shadow: none; }
.stage .graph-card h4 { color: var(--fg); }
.stage .graph-card .gc-kicker, .stage .graph-card .gc-note { color: var(--muted); }
.stage .graph-card .gc-note b { color: var(--fg); }
.stage .graph-card .gc-stat { background: rgba(255, 255, 255, .05); }
.stage .graph-card .gc-stat b { color: var(--fg); }
.stage .graph-card .gc-badge { background: rgba(var(--teal-rgb), .14); color: var(--teal); }
.stage .graph-card .gc-badge.wait { background: rgba(255, 255, 255, .06); color: var(--muted); }

/* HTML live readout under a 3D bench (replaces unreadable in-scene HUD text on phones) */
.bench-readout { display: grid; grid-template-columns: repeat(auto-fit, minmax(70px, 1fr)); gap: 6px; padding: 12px 14px 0; }
.bench-readout:empty { display: none; }
.bench-readout div { background: rgba(255, 255, 255, .05); border: 1px solid var(--line); border-radius: calc(12px * var(--corner, 1)); padding: 7px 8px; min-width: 0; }
.bench-readout span { display: block; font-family: var(--font-mono); font-size: 10.5px; letter-spacing: .02em; color: var(--muted); }
.bench-readout b { font-family: var(--font-mono); font-size: 15px; white-space: nowrap; color: var(--fg); font-variant-numeric: tabular-nums; }
.bench-readout .hot b { color: var(--amber); }

/* Equations: wrap on phones instead of clipping */
.eq { white-space: normal; overflow-wrap: anywhere; }
.eq.nowrap { white-space: nowrap; }

/* 3D stage zoom / recentre controls (added by SceneKit) */
.stage-zoom { position: absolute; right: 8px; bottom: 8px; display: flex; gap: 5px; z-index: 3; }
.stage-zoom button { width: 36px; height: 36px; border-radius: calc(11px * var(--corner, 1)); border: 1px solid rgba(255, 255, 255, .14); background: rgba(var(--ink-900-rgb), .6); color: #fff; font: 700 18px/1 var(--font-body); display: grid; place-items: center; cursor: pointer; backdrop-filter: blur(6px); -webkit-backdrop-filter: blur(6px); }
.stage-zoom button:active { transform: scale(.94); }
.stage-zoom svg { width: 18px; height: 18px; }
.no-webgl .stage-zoom { display: none; }
.stage-canvas canvas { touch-action: pan-y; }

/* Phone: tables become stacked cards so nobody scrolls sideways through dropdowns */
@media (max-width: 640px) {
  .tbl-wrap, .table-scroll { overflow-x: visible; }
  .tbl, .lab-table { min-width: 0; }
  .tbl.cards thead, .lab-table.cards thead { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); }
  .tbl.cards, .tbl.cards tbody, .lab-table.cards, .lab-table.cards tbody { display: block; width: 100%; }
  .tbl.cards tr, .lab-table.cards tr { display: grid; grid-template-columns: 1fr; padding: 10px 12px; border-bottom: 1px solid var(--paper-line); }
  .tbl.cards tr:last-child, .lab-table.cards tr:last-child { border-bottom: 0; }
  .tbl.cards td, .lab-table.cards td { display: flex; align-items: center; justify-content: space-between; gap: 12px; padding: 6px 0; border: 0; min-height: 0; }
  .tbl.cards td::before, .lab-table.cards td::before { content: attr(data-label); flex: 0 1 46%; font-family: var(--font-mono); font-size: 11px; letter-spacing: .02em; color: var(--paper-muted); line-height: 1.35; }
  .tbl.cards td:first-child, .lab-table.cards td:first-child { font-weight: 800; font-size: 15.5px; justify-content: flex-start; gap: 8px; padding-bottom: 4px; }
  .tbl.cards td:first-child::before, .lab-table.cards td:first-child::before { flex: none; }
  .lab-table.cards td:first-child { display: block; }
  .lab-table.cards td:first-child::before { display: block; margin-bottom: 2px; }
  .tbl.cards td > select, .lab-table.cards td > select { flex: 0 1 54%; min-height: 40px; }
  .tbl.cards td.ok, .tbl.cards td.no, .lab-table.cards td.ok, .lab-table.cards td.no { border-radius: calc(8px * var(--corner, 1)); padding: 6px 8px; margin: 2px -8px; }
  .lab-table.cards td.hint { display: block; font-size: 12.5px; color: var(--paper-muted); }
  .lab-table.cards td.hint::before { display: block; margin-bottom: 2px; }
  .tbl.cards td:empty, .lab-table.cards td:empty { display: none; }
  .tbl.cards td .td-v, .lab-table.cards td .td-v { flex: 1 1 54%; min-width: 0; }
  .tbl.cards td:first-child .td-v, .lab-table.cards td:first-child .td-v { flex: 1 1 auto; }
}
@media (max-width: 640px) {
  .stage:not(.story-stage) .stage-toast { top: auto; bottom: 50px; left: 8px; right: 8px; max-width: none; transform: translateY(8px); background: rgba(var(--ink-900-rgb), .82); color: var(--fg); border: 1px solid rgba(255, 255, 255, .14); font-size: 12.5px; font-weight: 600; line-height: 1.4; padding: 8px 12px; backdrop-filter: blur(6px); -webkit-backdrop-filter: blur(6px); }
  .stage:not(.story-stage) .stage-toast.show { transform: none; }
}
/* Physics symbols are case-sensitive (l ≠ L, r ≠ R, η ≠ H): never uppercase table headers */
.tbl th, .lab-table th { text-transform: none; letter-spacing: .02em; }

/* ---- SHM unit: lesson switcher (hero, identical in all 7 lessons) ---- */
.l-switch { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 14px; }
.l-switch a { min-width: 36px; text-align: center; padding: 6px 8px; border-radius: 999px; border: 1px solid var(--line-strong); color: var(--fg-soft); text-decoration: none; font: 600 12.5px var(--font-mono); }
.l-switch a[aria-current="page"] { background: var(--amber); border-color: var(--amber); color: var(--ink-950); }
.l-switch a.home { min-width: 0; }

/* ---- SHM unit: "story numbers are a model" note (one shared rule for every lesson) ---- */
p.note.model-note { width: auto; min-height: 0; padding: 8px 12px; margin: 12px 0 0; transform: none; animation: none; box-shadow: none; background: rgba(var(--amber-rgb), .12); border-left: 3px solid var(--amber); border-radius: calc(6px * var(--corner, 1)); font-family: var(--font-body); font-size: 13.5px; font-style: italic; color: var(--paper-ink); }
.bridge-card p.note.model-note, .l7-bridge p.note.model-note { color: var(--fg-soft); }