:root {
  --reference-paper: #fbfbfd;
  --reference-surface: #ffffff;
  --reference-ink: #171923;
  --reference-muted: #626978;
  --reference-line: #dfe3eb;
  --reference-blue: #435dcc;
  --reference-blue-soft: #eef1ff;
  --reference-orange: #d85d32;
  --reference-orange-soft: #fff1eb;
  --reference-green: #13705b;
}

html { scroll-behavior: smooth; }
body.reference-post { max-width: 1060px; background: var(--reference-paper); color: var(--reference-ink); }
.reading-progress { position: fixed; z-index: 100; inset: 0 0 auto; height: 3px; background: rgba(23, 25, 35, .1); }
.reading-progress span { display: block; width: 100%; height: 100%; background: linear-gradient(90deg, var(--reference-blue), #6e86ec, var(--reference-orange)); transform: scaleX(0); transform-origin: left; }
.skip-link { position: fixed; z-index: 20; top: .75rem; left: .75rem; padding: .65rem .8rem; color: white; background: var(--reference-ink); transform: translateY(-180%); }
.skip-link:focus { transform: translateY(0); }
.reference-post header { padding-bottom: 1rem; border-bottom: 1px solid var(--reference-line); }
.reference-post .post { max-width: none; padding-top: clamp(4rem, 9vw, 7.5rem); }
.post-hero { max-width: 840px; }
.reference-post h1 { max-width: 820px; margin-top: .8rem; font-family: var(--body); font-size: clamp(3.1rem, 7.2vw, 5.6rem); font-weight: 690; letter-spacing: -.06em; line-height: .96; }
.reference-post article { margin-top: clamp(5rem, 9vw, 8rem); font-size: 1.08rem; }
.myth { max-width: 700px; margin: clamp(2.5rem, 5vw, 4rem) 0 1.25rem; font-size: clamp(1.55rem, 3.2vw, 2.55rem); font-weight: 640; letter-spacing: -.035em; line-height: 1.12; }
.myth span { display: block; margin-bottom: .7rem; color: var(--reference-orange); font: 500 .65rem/1 var(--mono); letter-spacing: .08em; text-transform: uppercase; }
.stakes, .hero-promise { max-width: 690px; color: var(--reference-muted); font-size: clamp(1.08rem, 1.6vw, 1.25rem); line-height: 1.65; }
.hero-promise { margin-top: 1.1rem; color: var(--reference-ink); }

.lesson { padding: clamp(4.5rem, 9vw, 7.25rem) 0; border-top: 1px solid var(--reference-line); }
.section-copy { max-width: 760px; }
.section-index { margin: 0 0 1rem; color: var(--reference-blue); font: 500 .65rem/1.3 var(--mono); letter-spacing: .07em; text-transform: uppercase; }
.reference-post article h2 { margin: 0; font-family: var(--body); font-size: clamp(2.15rem, 4.5vw, 3.9rem); font-weight: 680; letter-spacing: -.05em; line-height: 1.02; }
.reference-post article h2 code { padding: 0; background: none; font: inherit; }
.section-copy > p:last-child:not(.section-index) { max-width: 680px; margin: 1.35rem 0 0; color: var(--reference-muted); font-size: 1.08rem; }
.reading { max-width: 720px; margin-top: 2rem; }
.reading p { margin: 0; font-size: clamp(1.05rem, 1.45vw, 1.16rem); line-height: 1.75; }
.reading p + p, .reading pre + p, .reading p + pre, .reading aside + p { margin-top: 1.2rem; }
.reading em { color: inherit; font-style: italic; }
.reading strong { font-weight: 700; }
.deep-note { margin-top: 1.25rem; border: 1px solid var(--reference-line); background: var(--reference-surface); }
.deep-note summary { padding: .85rem 1rem; color: var(--reference-blue); font-weight: 650; cursor: pointer; list-style-position: inside; }
.deep-note[open] summary { border-bottom: 1px solid var(--reference-line); }
.deep-note > p, .deep-note > pre, .deep-note > aside { margin: 1rem; }
.deep-note > p { font-size: 1rem; }
.open-thread, .final-question { max-width: 720px; margin: 2.5rem 0 0; padding-left: 1rem; color: #3e4658; border-left: 3px solid var(--reference-orange); font-style: italic; line-height: 1.65; }
.diagram-caption { margin: .8rem 0 0; color: var(--reference-muted); font: .7rem/1.5 var(--mono); }

.spatial-story { display: grid; grid-template-columns: minmax(370px, .42fr) minmax(520px, .58fr); align-items: start; width: min(1280px, calc(100vw - 2rem)); margin-left: 50%; border-top: 1px solid var(--reference-line); transform: translateX(-50%); }
.story-copy, .scene-column { grid-row: 1; min-width: 0; }
.story-copy { grid-column: 1; padding: 0 clamp(1rem, 2.5vw, 2.5rem) 0 0; }
.scene-column { grid-column: 2; position: relative; min-height: 100%; }
.story-step { min-height: 100vh; padding: clamp(4rem, 8vh, 6.5rem) 0; opacity: .52; transition: opacity .35s ease; }
.story-step.is-scene-active { opacity: 1; }
.story-copy .section-copy, .story-copy .reading, .story-copy .open-thread, .story-copy .copy-rule { max-width: none; }
.story-copy .reference-post article h2, .story-copy h2 { font-size: clamp(2rem, 3.4vw, 3.25rem); }
.story-copy .code-example, .story-copy .prediction, .story-copy .rule-pair, .story-copy .equality-grid, .story-copy .method-list { grid-template-columns: 1fr; }
.story-copy .prediction > pre { grid-row: auto; }
.story-copy .code-example > pre, .story-copy .prediction > pre { padding: 1.25rem; }
.story-copy .prediction fieldset { padding: 1.25rem; }
.story-copy .answer { padding: 0 1.25rem 1.25rem; }
.story-copy .value-demo { padding: 1rem; }
.story-copy .rule-pair { gap: .8rem; }
.story-copy .equality-grid > div { min-height: 125px; }
.story-copy .method-list { max-width: none; }

.scene-sticky { position: sticky; top: 1rem; height: calc(100vh - 2rem); min-height: 620px; overflow: hidden; color: #f4f6ff; border: 1px solid #343a4c; background: #171a23; box-shadow: 0 26px 70px rgba(24, 29, 48, .18); }
.scene-sticky::before { content: ""; position: absolute; inset: 0; pointer-events: none; background: radial-gradient(circle at 60% 30%, rgba(67, 93, 204, .17), transparent 38%), linear-gradient(rgba(255,255,255,.035) 1px, transparent 1px), linear-gradient(90deg, rgba(255,255,255,.035) 1px, transparent 1px); background-size: auto, 34px 34px, 34px 34px; }
.scene-heading { position: absolute; z-index: 4; top: 1.2rem; left: 1.25rem; right: 1.25rem; display: flex; align-items: baseline; justify-content: space-between; gap: 1rem; pointer-events: none; }
.scene-heading p { margin: 0; color: #91a5ff; font: .62rem var(--mono); letter-spacing: .08em; text-transform: uppercase; }
.scene-heading h3 { max-width: 18rem; margin: 0; color: #f4f6ff; font: 600 clamp(1.1rem, 2vw, 1.55rem)/1.05 var(--body); letter-spacing: -.035em; text-align: right; }
.scene-viewport { position: absolute; inset: 4.6rem 0 9.7rem; }
.scene-viewport canvas { display: block; width: 100%; height: 100%; opacity: 0; touch-action: none; transition: opacity .35s ease; }
.spatial-ready .scene-viewport canvas { opacity: 1; }
.scene-loader { position: absolute; z-index: 3; inset: 0; display: grid; place-content: center; gap: .75rem; color: #aeb5c8; font: .68rem var(--mono); text-align: center; }
.scene-loader span { justify-self: center; width: 26px; height: 26px; border: 2px solid #3c4356; border-top-color: #8da0ff; border-radius: 50%; animation: loader-spin .8s linear infinite; }
.spatial-ready .scene-loader { display: none; }
@keyframes loader-spin { to { transform: rotate(1turn); } }
.scene-fallback { position: absolute; z-index: 2; inset: 12% 9%; display: grid; grid-template-columns: .7fr .4fr 1fr; grid-template-rows: 1fr 1fr; gap: 1.2rem; align-items: center; opacity: .85; }
.spatial-ready .scene-fallback { display: none; }
.fallback-name, .fallback-object { padding: .9rem; border: 1px solid #536074; background: #202531; font: .68rem var(--mono); }
.fallback-name { color: #afbcff; border-left: 3px solid #7389ed; }
.fallback-object { grid-column: 3; grid-row: 1 / -1; color: #ffb99f; border-color: #ab573c; }
.fallback-object span, .fallback-object b { display: block; }
.fallback-object b { margin-top: .55rem; color: #fff; font-size: 1rem; }
.scene-fallback i { height: 2px; background: #7186e6; }
.scene-gesture { position: absolute; z-index: 4; right: 1rem; bottom: .6rem; margin: 0; color: #8f98ab; font: .57rem var(--mono); pointer-events: none; }
.scene-controls { position: absolute; z-index: 5; left: 1.1rem; right: 1.1rem; bottom: 4.5rem; display: grid; grid-template-columns: 1.4fr .8fr .8fr; gap: .55rem; }
.scene-controls button { min-height: 42px; padding: .62rem .75rem; color: #d9deec; border: 1px solid #3d4558; background: #222735; font: 600 .72rem var(--body); cursor: pointer; }
.scene-controls .scene-action { color: #131620; border-color: #8fa2ff; background: #91a5ff; }
.scene-controls button:hover { border-color: #c6d0ff; }
.scene-controls button:disabled { opacity: .42; cursor: not-allowed; }
.scene-status { position: absolute; z-index: 4; left: 1.2rem; right: 1.2rem; bottom: 1.9rem; margin: 0; color: #d3d9e8; font-size: .78rem; line-height: 1.4; }
.scene-help { position: absolute; z-index: 4; left: 1.2rem; right: 1.2rem; bottom: .65rem; margin: 0; color: #7f889b; font: .54rem var(--mono); }

.reference-lab { margin-top: 2.5rem; border: 1px solid var(--reference-line); background: var(--reference-surface); box-shadow: 0 18px 55px rgba(34, 42, 74, .07); }
.lab-code { display: grid; grid-template-columns: repeat(3, 1fr); border-bottom: 1px solid var(--reference-line); }
.code-line { display: flex; gap: .8rem; min-width: 0; padding: 1rem; color: var(--reference-muted); border: 0; border-right: 1px solid var(--reference-line); background: transparent; font: .72rem/1.5 var(--mono); text-align: left; cursor: pointer; }
.code-line:last-child { border-right: 0; }
.code-line span { flex: 0 0 auto; color: #9aa1af; }
.code-line code { overflow-wrap: anywhere; padding: 0; background: transparent; }
.code-line.is-next { color: var(--reference-ink); background: var(--reference-blue-soft); box-shadow: inset 0 -3px var(--reference-blue); }
.code-line.is-done { color: var(--reference-green); }
.code-line:disabled { cursor: default; opacity: .62; }
.memory-board { position: relative; min-height: 350px; overflow: hidden; background-image: linear-gradient(rgba(67, 93, 204, .05) 1px, transparent 1px), linear-gradient(90deg, rgba(67, 93, 204, .05) 1px, transparent 1px); background-size: 30px 30px; }
.board-label { position: absolute; top: 1.1rem; left: 4%; margin: 0; color: var(--reference-muted); font: .6rem var(--mono); letter-spacing: .08em; text-transform: uppercase; }
.board-label-object { left: auto; right: 18%; }
.binding, .heap-object { position: absolute; z-index: 2; border: 1px solid var(--reference-line); background: white; box-shadow: 0 8px 25px rgba(42, 50, 83, .07); }
.binding { left: 4%; display: flex; align-items: center; justify-content: space-between; width: 28%; min-width: 185px; padding: .95rem 1rem; border-left: 4px solid #c7cddb; opacity: .5; transform: translateX(-8px); }
.binding-profile { top: 22%; }
.binding-backup { top: 61%; }
.binding span, .heap-object > span { color: var(--reference-muted); font: .62rem var(--mono); text-transform: uppercase; }
.binding b { color: #9da4b2; font: 500 .68rem var(--mono); }
.binding.is-assigned { border-left-color: var(--reference-blue); opacity: 1; transform: none; }
.binding.is-assigned b { color: var(--reference-blue); }
.heap-object { top: 31%; right: 5%; width: 28%; min-width: 195px; padding: 1rem; border: 2px solid var(--reference-orange); border-radius: 4px; background: var(--reference-orange-soft); opacity: .22; transform: scale(.94); }
.heap-object.is-live { opacity: 1; transform: scale(1); }
.heap-object > span { color: #9e4224; }
.heap-object div { display: flex; align-items: baseline; justify-content: space-between; margin-top: .8rem; padding-top: .8rem; border-top: 1px solid #efbaa7; }
.heap-object code { padding: 0; background: transparent; }
.heap-object strong { font: 680 2.6rem/1 var(--body); letter-spacing: -.05em; }
.heap-object.is-mutated { animation: object-pulse .5s ease-out; }
@keyframes object-pulse { 45% { box-shadow: 0 0 0 12px rgba(216, 93, 50, .13); } }
.reference-wires { position: absolute; z-index: 1; inset: 0; width: 100%; height: 100%; overflow: visible; pointer-events: none; }
.wire { fill: none; stroke: var(--reference-blue); stroke-width: 3; stroke-linecap: round; stroke-dasharray: 1; stroke-dashoffset: 1; vector-effect: non-scaling-stroke; transition: stroke-dashoffset .55s ease; }
.wire.is-drawn { stroke-dashoffset: 0; }
.lab-controls { display: grid; grid-template-columns: auto auto 1fr; gap: .8rem; align-items: center; padding: 1rem; border-top: 1px solid var(--reference-line); }
.run-button, .reset-button, .prediction button { min-height: 44px; border: 1px solid var(--reference-ink); font: 650 .82rem var(--body); cursor: pointer; }
.run-button { padding: .65rem 1rem; color: white; background: var(--reference-ink); }
.reset-button { padding: .65rem .9rem; color: var(--reference-ink); background: white; }
.run-button:disabled, .reset-button:disabled { opacity: .45; cursor: default; }
.lab-status { justify-self: end; margin: 0; color: var(--reference-muted); font: .66rem var(--mono); }

.code-example, .prediction { display: grid; grid-template-columns: minmax(280px, 1fr) minmax(280px, .9fr); margin-top: 2.25rem; border: 1px solid var(--reference-line); background: white; }
.code-example > pre, .prediction > pre, .standalone-code, .rule-pair pre { margin: 0; overflow-x: auto; color: #edf0f8; background: #1c202b; font: .84rem/1.8 var(--mono); }
.code-example > pre, .prediction > pre { padding: clamp(1.35rem, 3.5vw, 2.5rem); }
.code-example code, .prediction pre code, .standalone-code code, .rule-pair pre code { padding: 0; background: transparent; }
.value-demo { display: grid; grid-template-columns: 1fr 1fr; gap: 1px; align-content: center; padding: clamp(1.35rem, 3.5vw, 2.5rem); background: var(--reference-line); }
.value-demo div { display: grid; place-items: center; min-height: 150px; padding: 1rem; background: var(--reference-surface); }
.value-demo span, .value-demo small { color: var(--reference-muted); font: .62rem var(--mono); text-transform: uppercase; }
.value-demo strong { font-size: 2.4rem; }
.value-demo div:first-child strong { color: var(--reference-blue); }

.rule-pair { display: grid; grid-template-columns: 1fr 1fr; gap: 1.25rem; margin-top: 2.25rem; }
.rule-pair > div { border: 1px solid var(--reference-line); background: var(--reference-surface); }
.rule-pair > div > p { margin: 0; padding: 1rem; line-height: 1.55; }
.rule-pair > div > p:first-child { color: var(--reference-blue); border-bottom: 1px solid var(--reference-line); font-weight: 700; }
.rule-pair pre { padding: 1.25rem; font-size: .76rem; }
.rule-pair > div > p:last-child { color: var(--reference-muted); font-size: .94rem; }

.prediction > pre { grid-row: 1 / span 2; }
.prediction fieldset { display: grid; grid-template-columns: repeat(3, 1fr); gap: .65rem; align-content: start; margin: 0; padding: clamp(1.35rem, 3.5vw, 2.5rem); border: 0; }
.prediction legend { grid-column: 1 / -1; width: 100%; margin-bottom: 1rem; font-weight: 650; line-height: 1.4; }
.prediction button { padding: .7rem; color: var(--reference-ink); background: var(--reference-paper); }
.prediction button:hover { border-color: var(--reference-blue); background: var(--reference-blue-soft); }
.prediction button[aria-pressed="true"] { color: white; border-color: var(--reference-blue); background: var(--reference-blue); }
.prediction button:disabled:not([aria-pressed="true"]) { opacity: .45; cursor: default; }
.answer { padding: 0 clamp(1.35rem, 3.5vw, 2.5rem) clamp(1.35rem, 3.5vw, 2.5rem); }
.answer-result { margin: 0 0 .65rem; color: var(--reference-green); font: 600 .68rem var(--mono); letter-spacing: .07em; text-transform: uppercase; }
.answer p:last-child { margin-bottom: 0; line-height: 1.6; }
.shallow-prediction fieldset { grid-template-columns: repeat(2, 1fr); }
.standalone-code { padding: 1.35rem; border-radius: 2px; font-size: .8rem; }
.plain-note { margin-top: 1.4rem; padding: 1.1rem 1.2rem; color: #343d55; border: 1px solid #c7d0f8; background: var(--reference-blue-soft); line-height: 1.6; }
.plain-note strong { display: block; margin-bottom: .25rem; color: var(--reference-blue); }
.copy-rule { max-width: 720px; margin-top: 2rem; padding: 1rem 1.2rem; border: 1px solid #c7d0f8; background: var(--reference-blue-soft); line-height: 1.6; }

.shallow-map { display: grid; grid-template-columns: 1fr 1fr; gap: .65rem; margin: .4rem 0 1rem; }
.root-object, .shared-object { padding: .75rem; border: 1px solid #bdc8f0; background: var(--reference-blue-soft); }
.shared-object { grid-column: 1 / -1; position: relative; margin-top: 1.2rem; border-color: #efbaa7; background: var(--reference-orange-soft); }
.shared-object::before, .shared-object::after { content: ""; position: absolute; bottom: 100%; width: 1px; height: 1.2rem; background: var(--reference-blue); }
.shared-object::before { left: 25%; transform: rotate(-25deg); transform-origin: bottom; }
.shared-object::after { right: 25%; transform: rotate(25deg); transform-origin: bottom; }
.shallow-map span { display: block; margin-bottom: .2rem; color: var(--reference-muted); font: .57rem var(--mono); text-transform: uppercase; }
.shallow-map b { font-size: .8rem; }

.equality-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 1px; margin-top: 2.25rem; border: 1px solid var(--reference-line); background: var(--reference-line); }
.equality-grid > div { display: grid; grid-template-columns: 1fr auto; gap: .6rem 1rem; min-height: 145px; padding: 1.25rem; background: var(--reference-surface); }
.equality-grid code { align-self: start; padding: 0; background: none; font-size: .75rem; }
.equality-grid strong { color: var(--reference-orange); font: 600 .74rem var(--mono); text-transform: uppercase; }
.equality-grid p { grid-column: 1 / -1; align-self: end; margin: 0; color: var(--reference-muted); font-size: .92rem; }
.method-list { display: grid; grid-template-columns: 1fr 1fr; max-width: 820px; gap: 1px; margin-top: 2rem; border: 1px solid var(--reference-line); background: var(--reference-line); }
.method-list div { padding: 1.2rem; background: var(--reference-surface); }
.method-list span { display: block; margin-bottom: .5rem; color: var(--reference-muted); font-size: .88rem; }
.method-list code { padding: 0; background: none; color: var(--reference-blue); font-size: .76rem; }

.sticker { max-width: 900px; margin: 2.5rem 0 0; padding: clamp(1.2rem, 3.5vw, 2.5rem); color: white; background: #1c202b; box-shadow: 10px 10px 0 var(--reference-blue); }
.sticker figcaption { margin-bottom: 1.75rem; color: #b8c2f0; font: .62rem var(--mono); letter-spacing: .08em; text-transform: uppercase; }
.sticker-columns { display: grid; grid-template-columns: 1fr 1fr; gap: 1px; background: #414758; }
.sticker-case { min-height: 245px; padding: 1.4rem; background: #1c202b; }
.sticker-case > p { margin-bottom: 1.5rem; color: #bfc5d2; font: .66rem var(--mono); text-transform: uppercase; }
.mini-row { display: grid; grid-template-columns: 42px 1fr; align-items: center; margin: .65rem 0; }
.mini-row span, .alias-row span { color: #bdc8f4; font: .76rem var(--mono); }
.mini-row b { width: 54px; padding: .35rem; color: var(--reference-ink); background: #eef1ff; text-align: center; }
.sticker-case > strong { display: block; margin-top: 1.8rem; color: #eef1ff; font-size: 1.1rem; }
.object-case { position: relative; }
.alias-row { display: grid; grid-template-columns: 42px 1fr; align-items: center; width: 52%; margin: .7rem 0; }
.alias-row i { height: 2px; background: #8398ef; }
.mini-object { position: absolute; top: 5rem; right: 1.4rem; width: 42%; padding: 1.2rem .6rem; border: 2px solid #ed875f; color: #ffddcf; background: #39261f; font: .68rem var(--mono); text-align: center; }
.sticker blockquote { max-width: 720px; margin: 2.2rem 0 0; font-size: clamp(1.55rem, 3.2vw, 2.5rem); font-weight: 640; letter-spacing: -.035em; line-height: 1.1; }
.recap-list { display: grid; grid-template-columns: 1fr 1fr; max-width: 820px; gap: 0 2rem; margin-top: 2.5rem; }
.recap-list p { margin: 0; padding: .85rem 0; border-bottom: 1px solid var(--reference-line); }
.recap-list strong { color: var(--reference-blue); font-family: var(--mono); font-size: .72rem; }
.bring-home .final-question { color: var(--reference-blue); border-color: var(--reference-blue); font-style: normal; font-weight: 650; }
.reference-post footer a { color: inherit; }

button:focus-visible, a:focus-visible { outline: 3px solid var(--reference-orange); outline-offset: 3px; }
.no-js .binding { border-left-color: var(--reference-blue); opacity: 1; transform: none; }
.no-js .binding b { color: var(--reference-blue); font-size: 0; }
.no-js .binding b::after { content: "same object"; font-size: .68rem; }
.no-js .heap-object { opacity: 1; transform: none; }
.no-js [data-score] { font-size: 0; }
.no-js [data-score]::after { content: "1"; font-size: 2.6rem; }
.no-js .wire { stroke-dashoffset: 0; }
.no-js .lab-controls, .no-js .prediction fieldset { display: none; }
.no-js .answer[hidden] { display: block; }
.no-js .answer-result { display: none; }
.no-js .story-step { opacity: 1; }
.no-js .scene-controls, .no-js .scene-loader, .no-js .scene-help, .no-js .scene-gesture, .no-js .scene-status { display: none; }

@media (max-width: 720px) {
  body.reference-post { padding-inline: 1rem; }
  .reference-post h1 { font-size: clamp(2.9rem, 13vw, 4.4rem); }
  .lab-code { grid-template-columns: 1fr; }
  .code-line { border-right: 0; border-bottom: 1px solid var(--reference-line); }
  .memory-board { min-height: 420px; }
  .board-label { top: 1rem; }
  .board-label-object { top: 17.6rem; right: auto; left: 4%; }
  .binding { left: 4%; width: 92%; min-width: 0; }
  .binding-profile { top: 12%; }
  .binding-backup { top: 33%; }
  .heap-object { top: 70%; right: 4%; width: 92%; min-width: 0; }
  .reference-wires { display: none; }
  .binding.is-assigned::after { content: "↓ same object"; position: absolute; right: 1rem; top: calc(100% + .3rem); color: var(--reference-blue); font: .55rem var(--mono); }
  .lab-controls { grid-template-columns: 1fr auto; }
  .lab-status { grid-column: 1 / -1; grid-row: 2; justify-self: start; }
  .code-example, .prediction, .rule-pair, .equality-grid, .method-list, .sticker-columns, .recap-list { grid-template-columns: 1fr; }
  .prediction > pre { grid-row: auto; }
  .prediction fieldset { grid-template-columns: 1fr; }
  .shallow-prediction fieldset { grid-template-columns: 1fr 1fr; }
  .sticker { box-shadow: 7px 7px 0 var(--reference-blue); }
}

@media (max-width: 960px) {
  .spatial-story { grid-template-columns: 1fr; width: min(100%, 680px); }
  .story-copy, .scene-column { grid-column: 1; grid-row: 1; }
  .story-copy { z-index: 1; padding: 44vh 0 0; }
  .scene-column { z-index: 3; align-self: stretch; height: 100%; min-height: 100%; pointer-events: none; }
  .scene-sticky { top: 0; height: 42vh; min-height: 300px; pointer-events: auto; box-shadow: 0 12px 35px rgba(24, 29, 48, .22); }
  .scene-heading { top: .75rem; left: .85rem; right: .85rem; }
  .scene-heading h3 { font-size: 1rem; }
  .scene-viewport { inset: 3rem 0 6.6rem; }
  .scene-controls { left: .7rem; right: .7rem; bottom: 2.65rem; grid-template-columns: 1.4fr .8fr; }
  .scene-controls button { min-height: 36px; padding: .4rem .55rem; font-size: .64rem; }
  .scene-controls button[data-scene-reset] { display: none; }
  .scene-status { left: .8rem; right: .8rem; bottom: .85rem; overflow: hidden; white-space: nowrap; text-overflow: ellipsis; font-size: .67rem; }
  .scene-help, .scene-gesture { display: none; }
  .story-step { min-height: auto; padding: 4.5rem 0; opacity: 1; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .heap-object.is-mutated { animation: none; }
  .wire { transition: none; }
  .story-step, .scene-viewport canvas { transition: none; }
  .scene-loader span { animation: none; }
}