:root {
  --bg: #05060a;
  --ink: #eef1f6;
  --ink-2: #a9b0bd;
  --ink-3: #6c7380;
  --panel: rgba(14, 16, 22, 0.62);
  --panel-line: rgba(255, 255, 255, 0.08);
  --cyan: #5ee7ff;
  --amber: #ffb347;
  --red: #ff5a5a;
  --serif: "Instrument Serif", Georgia, serif;
  --sans: "Inter", system-ui, -apple-system, sans-serif;
  --mono: "JetBrains Mono", ui-monospace, monospace;
}

* { box-sizing: border-box; }
html { scroll-behavior: auto; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

#scene {
  position: fixed;
  inset: 0;
  width: 100vw;
  height: 100vh;
  display: block;
  z-index: 0;
}
body.orbiting #scene { cursor: grab; }
body.orbiting #scene:active { cursor: grabbing; }

/* model-specific copy */
body.model-film [data-phone],
body.model-phone [data-film] { display: none; }

/* ---------- top bar ---------- */
.topbar {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 16px clamp(16px, 3vw, 32px);
  pointer-events: none;
}
.topbar > * { pointer-events: auto; }
.brand {
  display: flex; align-items: center; gap: 10px;
  font-weight: 600; letter-spacing: 0.18em; text-transform: uppercase; font-size: 12px;
  color: var(--ink-2);
}
.brand-iris {
  width: 18px; height: 18px; border-radius: 50%;
  background: conic-gradient(from 0deg, #2a2d35 0 12.5%, #1a1c22 0 25%, #2a2d35 0 37.5%, #1a1c22 0 50%, #2a2d35 0 62.5%, #1a1c22 0 75%, #2a2d35 0 87.5%, #1a1c22 0);
  box-shadow: inset 0 0 0 5px transparent, 0 0 0 1px rgba(255,255,255,.18);
  position: relative;
}
.brand-iris::after {
  content: ""; position: absolute; inset: 6px; border-radius: 50%;
  background: radial-gradient(circle, #fff 0, var(--cyan) 60%, transparent 100%);
}
.model-switch {
  display: flex;
  padding: 4px;
  border-radius: 999px;
  background: var(--panel);
  border: 1px solid var(--panel-line);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
}
.model-switch button {
  appearance: none; border: 0; cursor: pointer;
  font: 500 13px/1 var(--sans);
  color: var(--ink-2);
  background: transparent;
  padding: 9px 14px;
  border-radius: 999px;
  transition: background .25s, color .25s;
  white-space: nowrap;
}
.model-switch button[aria-checked="true"] { background: rgba(255,255,255,.12); color: var(--ink); }
.model-switch button:focus-visible { outline: 2px solid var(--cyan); outline-offset: 2px; }

/* ---------- HUD ---------- */
.hud {
  position: fixed;
  right: clamp(16px, 3vw, 32px);
  bottom: clamp(16px, 3vw, 32px);
  z-index: 15;
  width: 240px;
  padding: 14px 16px 16px;
  border-radius: 16px;
  background: var(--panel);
  border: 1px solid var(--panel-line);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  opacity: 0;
  transform: translateY(10px);
  transition: opacity .5s, transform .5s;
  pointer-events: none;
}
.hud.on { opacity: 1; transform: none; }
.hud-f { display: flex; align-items: baseline; justify-content: space-between; margin-bottom: 8px; }
.hud-f-label { font-size: 11px; letter-spacing: .14em; text-transform: uppercase; color: var(--ink-3); }
#hud-fnum { font-family: var(--mono); font-size: 28px; font-weight: 500; letter-spacing: -0.02em; }
.hud-row { display: grid; grid-template-columns: 84px 1fr; align-items: center; gap: 10px; font-size: 12px; color: var(--ink-2); margin-top: 6px; }
.bar { height: 6px; border-radius: 3px; background: rgba(255,255,255,.08); overflow: hidden; }
.bar i { display: block; height: 100%; width: 50%; border-radius: 3px; background: linear-gradient(90deg, #fff, var(--cyan)); }
.bar i.warm { background: linear-gradient(90deg, var(--amber), #ff6a6a); }
.sensor-view {
  margin-top: 12px;
  position: relative;
  max-height: 0;
  opacity: 0;
  overflow: hidden;
  transition: max-height .5s, opacity .5s;
}
.sensor-view.on { max-height: 200px; opacity: 1; }
#sensor-view { filter: brightness(3); display: block; width: 100%; height: auto; aspect-ratio: 3 / 2; border-radius: 8px; background: #000; }
.sv-label { position: absolute; left: 8px; top: 6px; font-size: 10px; letter-spacing: .1em; text-transform: uppercase; color: rgba(255,255,255,.55); }

/* ---------- 3D labels ---------- */
#labels { position: fixed; inset: 0; pointer-events: none; z-index: 5; }
.label {
  position: absolute; left: 0; top: 0;
  transform: translate(-50%, -100%);
  display: flex; flex-direction: column; align-items: center;
  font-size: 12px; font-weight: 500; color: var(--ink);
  white-space: nowrap;
  opacity: 0;
  will-change: transform, opacity;
}
.label b {
  font-weight: 500;
  padding: 4px 9px;
  border-radius: 999px;
  background: rgba(10, 12, 18, .72);
  border: 1px solid rgba(255,255,255,.14);
}
.label::after { content: ""; width: 1px; height: 22px; background: linear-gradient(rgba(255,255,255,.5), rgba(255,255,255,0)); }
.label.amber b { border-color: rgba(255,179,71,.5); color: #ffd59b; }
.label.red b { border-color: rgba(255,90,90,.5); color: #ffb3b3; }
.label.cyan b { border-color: rgba(94,231,255,.45); color: #c6f6ff; }

/* ---------- content ---------- */
#content { position: relative; z-index: 10; pointer-events: none; }
/* Contain the mobile card's top margin so adjacent scroll timelines meet. */
section { display: flow-root; position: relative; height: 260vh; }
section.hero { height: 150vh; }
section.play { height: 170vh; }

.hero-inner {
  position: sticky; top: 0;
  height: 100vh;
  display: flex; flex-direction: column; justify-content: flex-end;
  padding: 0 clamp(16px, 6vw, 96px) 12vh;
  max-width: 900px;
}
.eyebrow { font-size: 12px; letter-spacing: .2em; text-transform: uppercase; color: var(--cyan); margin: 0 0 12px; }
h1 {
  font-family: var(--serif); font-weight: 400;
  font-size: clamp(48px, 8vw, 112px); line-height: .95; letter-spacing: -0.02em;
  margin: 0 0 20px;
  text-wrap: balance;
}
h1 em, h2 em { font-style: italic; color: #fff; }
.lede { font-size: clamp(17px, 1.6vw, 20px); color: var(--ink-2); max-width: 34em; margin: 0 0 28px; }
.swatches { display: flex; gap: 10px; margin: 0 0 22px; pointer-events: auto; }
body.model-phone .swatches { display: flex; }
.swatches button {
  appearance: none; cursor: pointer;
  width: 22px; height: 22px; border-radius: 50%;
  background: var(--sw); border: 0;
  box-shadow: inset 0 0 0 1px rgba(255,255,255,.25), 0 0 0 2px transparent;
  transition: box-shadow .2s;
}
.swatches button[aria-checked="true"] { box-shadow: inset 0 0 0 1px rgba(255,255,255,.25), 0 0 0 2px var(--bg), 0 0 0 3.5px rgba(255,255,255,.8); }
.swatches button:focus-visible { outline: 2px solid var(--cyan); outline-offset: 3px; }
.scroll-hint { font-size: 13px; color: var(--ink-3); margin: 0; }
.scroll-hint span { display: inline-block; animation: bob 1.8s ease-in-out infinite; }
@keyframes bob { 50% { transform: translateY(4px); } }

.card {
  position: sticky;
  top: 15vh;
  margin-left: clamp(16px, 5vw, 80px);
  width: min(420px, calc(100vw - 32px));
  padding: 26px 28px;
  border-radius: 20px;
  background: var(--panel);
  border: 1px solid var(--panel-line);
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
  pointer-events: auto;
  opacity: 0;
  transform: translateY(16px);
  transition: opacity .25s ease-out, transform .25s ease-out;
}
.card.on { opacity: 1; transform: none; }
.num { font-family: var(--mono); font-size: 11px; letter-spacing: .08em; text-transform: uppercase; color: var(--cyan); margin: 0 0 10px; }
h2 { font-family: var(--serif); font-weight: 400; font-size: clamp(30px, 3vw, 40px); line-height: 1.05; margin: 0 0 16px; text-wrap: balance; }
.card p { margin: 0 0 12px; color: var(--ink-2); font-size: 15px; }
.card p strong { color: var(--ink); font-weight: 600; }
.card p.aside { font-size: 13.5px; color: var(--ink-3); border-left: 2px solid rgba(94,231,255,.4); padding-left: 12px; margin-top: 16px; margin-bottom: 0; }
.k-amber { color: var(--amber); }
.k-cyan { color: var(--cyan); }

.chart { margin: 14px 0 0; }
.chart svg { width: 100%; height: auto; display: block; }
.chart figcaption { font-size: 11.5px; color: var(--ink-3); margin-top: 4px; }

/* controls */
.control { margin: 18px 0 6px; }
.control label { display: flex; justify-content: space-between; font-size: 13px; color: var(--ink-2); margin-bottom: 8px; }
.control output { font-family: var(--mono); color: var(--ink); }
input[type="range"] {
  -webkit-appearance: none; appearance: none;
  width: 100%; height: 6px; border-radius: 3px;
  background: rgba(255,255,255,.12);
  outline: none;
}
input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none; appearance: none;
  width: 20px; height: 20px; border-radius: 50%;
  background: #fff; border: 0; box-shadow: 0 0 0 4px rgba(94,231,255,.25);
  cursor: pointer;
}
input[type="range"]::-moz-range-thumb { width: 20px; height: 20px; border-radius: 50%; background: #fff; border: 0; cursor: pointer; }
input[type="range"]:focus-visible::-webkit-slider-thumb { box-shadow: 0 0 0 4px var(--cyan); }
.stops { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 10px; }
.stops button {
  appearance: none; cursor: pointer;
  font: 500 12px/1 var(--mono);
  color: var(--ink-2);
  background: rgba(255,255,255,.06);
  border: 1px solid var(--panel-line);
  border-radius: 8px;
  padding: 7px 8px;
}
.stops button.active { color: #000; background: var(--cyan); border-color: var(--cyan); }

.outro {
  position: relative;
  pointer-events: auto;
  padding: 60px clamp(16px, 5vw, 80px) 80px;
  max-width: 640px;
  font-size: 13px;
  color: var(--ink-3);
}

/* ---------- mobile ---------- */
@media (max-width: 1000px) {
  .topbar { padding: 12px 16px; }
  .brand { font-size: 11px; }
  .model-switch button { padding: 8px 10px; font-size: 12px; }
  .hud {
    top: 62px; bottom: auto; left: 16px; right: 16px; width: auto;
    padding: 8px 10px;
    display: grid;
    grid-template-columns: auto 1fr auto;
    grid-template-areas: "f r1 sv" "f r2 sv";
    column-gap: 12px;
    align-items: center;
  }
  .hud > :nth-child(1) { grid-area: f; }
  .hud > :nth-child(2) { grid-area: r1; }
  .hud > :nth-child(3) { grid-area: r2; }
  .hud > :nth-child(4) { grid-area: sv; }
  .hud-f { margin: 0; }
  .hud-f-label { display: none; }
  #hud-fnum { font-size: 22px; }
  .hud-row { grid-template-columns: 62px 1fr; gap: 6px; font-size: 10.5px; margin: 2px 0; }
  .sensor-view { margin: 0; width: 0; transition: width .5s, opacity .5s; }
  .sensor-view.on { width: clamp(100px, 20vw, 144px); max-height: 100px; }
  .sv-label { display: none; }
  /* cards scroll past over the fixed scene: no sticky, no nested scrolling */
  .card {
    position: relative;
    top: auto;
    margin: 62vh auto 0;
    width: calc(100% - 32px);
    max-width: 560px;
    padding: 18px 18px;
  }
  .chart { max-width: 360px; }
  h2 { font-size: 26px; }
  .card p { font-size: 14px; }
  .hero-inner { padding-bottom: 10vh; }
}
@media (max-width: 420px) {
  .brand { display: none; }
}
@media (prefers-reduced-motion: reduce) {
  .scroll-hint span { animation: none; }
}

/* Product study — Burgundy */
:root {
  --bg: #000; --ink: #f5f5f7; --ink-2: #a1a1a6; --ink-3: #86868b;
  --panel: rgba(17,17,19,.78); --panel-line: rgba(255,255,255,.09);
  --cyan: #e4a9b5; --sans: -apple-system, BlinkMacSystemFont, 'Inter', sans-serif;
}
a { color: inherit; text-decoration: none; }
a:focus-visible, button:focus-visible { outline: 2px solid #edb7c1; outline-offset: 6px; }
.topbar { height: 64px; padding: 0 max(6vw, 24px); background: rgba(0,0,0,.78); backdrop-filter: blur(20px); border-bottom: 1px solid #ffffff20; }
.brand { font-size: 20px; color: #f5f5f7; font-weight: 600; letter-spacing: -.7px; text-transform: none; }
.topbar nav { display: flex; align-items: center; gap: 30px; font-size: 12px; color: #c4c4c8; }
.topbar nav a:hover { color: #fff; }
.nav-cta { padding: 9px 16px; border-radius: 24px; background: #f5f5f7; color: #18181b !important; }
.nav-cta span { margin-left: 8px; }
.reading-progress { position: absolute; bottom: -1px; left: 0; width: 100%; height: 1px; }
.reading-progress i { display: block; width: 100%; height: 100%; background: #df9ba9; transform: scaleX(0); transform-origin: left; }
section.hero { height: 135vh; }
.hero-inner { max-width: none; align-items: center; justify-content: flex-start; padding: max(110px, 12vh) 24px 0; text-align: center; }
.eyebrow { font-size: 14px; letter-spacing: .025em; text-transform: none; color: #d4bdc2; font-weight: 600; margin-bottom: 18px; }
h1 { font-family: var(--sans); font-size: clamp(54px, 6.7vw, 104px); font-weight: 650; line-height: 1.02; letter-spacing: -.065em; margin-bottom: 22px; }
h1 em { font-style: normal; background: linear-gradient(110deg,#f5dce2,#d79aa8 50%,#9b5265); background-clip: text; -webkit-background-clip: text; color: transparent; }
.lede { font-size: clamp(16px, 1.4vw, 21px); line-height: 1.45; letter-spacing: -.025em; margin: 0 0 18px; color: #9c9699; }
.hero-link { pointer-events: auto; font-size: 14px; color: #e6c1ca; }
.hero-link span { display: inline-block; margin-left: 8px; }
.finish-label { position: absolute; bottom: 28px; left: 6vw; font-size: 12px; color: #e6d0d6; display: flex; align-items: center; gap: 10px; }
.finish-label i { width: 12px; height: 12px; border-radius: 50%; background: #67303e; box-shadow: inset 0 0 0 1px #ffffff30; }
.finish-label span { color: #8e8489; margin-left: 12px; }
section:not(.hero) { height: 180vh; }
/* Give camera travel more room; keep smaller optical changes concise. */
section[data-ch="focus"] { height: 220vh; }
section[data-ch="close"] { height: 190vh; }
section[data-ch="blur"], section[data-ch="dof"] { height: 150vh; }
section.play { height: 150vh; }
.card { top: 20vh; width: min(430px, 34vw); margin-left: 6vw; padding: 0; border: 0; background: linear-gradient(90deg,rgba(0,0,0,.88),rgba(0,0,0,.38)); backdrop-filter: blur(12px); border-radius: 0; }
.card .num { color: #c98c9c; font-family: var(--sans); font-size: 12px; font-weight: 600; letter-spacing: .09em; margin-bottom: 22px; }
h2 { font-family: var(--sans); font-size: clamp(36px, 3.6vw, 58px); font-weight: 650; letter-spacing: -.055em; line-height: 1.05; margin-bottom: 28px; }
h2 em { font-style: normal; color: #d6a3b0; }
.card p { font-size: 16px; line-height: 1.6; letter-spacing: -.02em; margin-bottom: 18px; }
.card p.aside { font-size: 13px; border-color: #74434f; color: #8e8589; }
.hud { right: 6vw; bottom: 32px; border-radius: 22px; background: rgba(22,19,21,.8); box-shadow: 0 16px 60px #0006; padding: 18px 20px; }
.hud-f-label { color: #bba5ad; }
.label b { background: rgba(22,19,21,.85); padding: 6px 12px; }
.chapter-nav { position: fixed; z-index: 21; right: 22px; top: 44%; display: flex; flex-direction: column; gap: 16px; transition: opacity .3s; }
.chapter-nav a { width: 6px; height: 6px; border-radius: 50%; background: #51454a; position: relative; }
.chapter-nav a::after { content: ''; position: absolute; inset: -6px; }
.chapter-nav a[aria-current] { background: #efc1cf; box-shadow: 0 0 0 4px #b8798d26; }
.chapter-nav span { position: absolute; right: 18px; top: -7px; font-size: 11px; opacity: 0; transition: opacity .2s; }
.chapter-nav a:hover span, .chapter-nav a:focus-visible span { opacity: 1; }
body[data-chapter="hero"] .chapter-nav { opacity: 0; pointer-events: none; }
.control { padding: 16px 0; border-top: 1px solid #ffffff16; }
.stops { gap: 8px; }
.stops button { padding: 10px 14px; border-radius: 20px; }
.outro { max-width: none; background: #101012; padding: 64px 6vw 40px; }
.outro > p { max-width: 620px; font-size: 12px; }
.back-top { display: block; font-size: clamp(26px,4vw,48px); font-weight: 600; color: #ded7dc; letter-spacing: -.04em; margin-bottom: 64px; }
.footer-brand { color: #d4c7cd; }
.footer-brand span { color: #797579; }
@media (max-width: 1000px) {
  .topbar { padding: 0 24px; }
  .topbar nav { gap: 20px; }
  .hero-inner { padding-top: 120px; }
  h1 { font-size: clamp(55px, 9vw, 84px); }
  .card { width: calc(100% - 48px); max-width: 550px; margin: 70vh auto 0; padding: 28px; border-radius: 24px; background: rgba(15,13,15,.92); border: 1px solid #ffffff12; }
  h2 { font-size: 40px; }
  .card p { font-size: 15px; }
  .hud { top: 78px; left: 24px; right: 24px; bottom: auto; padding: 10px 14px; border-radius: 16px; }
  .chapter-nav { right: 10px; }
}
@media (max-width: 600px) {
  .topbar { height: 58px; padding: 0 20px; }
  .brand { display: flex; font-size: 17px; }
  .topbar nav > a:not(.nav-cta) { display: none; }
  .nav-cta { padding: 8px 12px; font-size: 11px; }
  .hero-inner { padding-top: 110px; }
  .eyebrow { font-size: 11px; }
  h1 { font-size: clamp(44px,11.6vw,68px); }
  .lede { font-size: 15px; }
  .finish-label { left: 24px; bottom: 24px; }
  .finish-label span { display: none; }
  .card { padding: 24px; }
  h2 { font-size: 36px; }
}
@media (prefers-reduced-motion: reduce) { *, *::before, *::after { animation: none !important; transition: none !important; } }

/* Measurements from Apple's iPhone 18 Pro camera page (8 October 2026). */
:root {
  --sans: 'SF Pro Text', -apple-system, BlinkMacSystemFont, 'Helvetica Neue', Helvetica, Arial, sans-serif;
  --display: 'SF Pro Display', -apple-system, BlinkMacSystemFont, 'Helvetica Neue', Helvetica, Arial, sans-serif;
  --mono: var(--sans);
  --ink-2: #86868b; --ink-3: #6e6e73;
}
body { font-size: 17px; line-height: 1.47059; letter-spacing: -.022em; }
.topbar { top: 9px; left: max(24px, calc((100% - 1024px)/2)); right: max(24px, calc((100% - 1024px)/2)); height: 54px; padding: 0 20px; border: 1px solid #ffffff16; border-radius: 24px; background: rgba(22,22,23,.8); backdrop-filter: saturate(180%) blur(20px); }
.brand { font-family: var(--display); font-size: 21px; font-weight: 600; letter-spacing: .011em; }
.topbar nav { gap: 20px; font-size: 12px; letter-spacing: -.01em; }
.nav-cta { background: #0071e3; color: #fff !important; padding: 7px 12px; }
.nav-cta:hover { background: #0077ed; }
.reading-progress { left: 24px; width: calc(100% - 48px); }
h1, h2, .back-top { font-family: var(--display); font-weight: 600; letter-spacing: -.015em; }
h1 { font-size: 80px; line-height: 1.05; }
h1 em { background: none; color: #f5f5f7; }
.eyebrow { font-family: var(--display); font-size: 21px; font-weight: 600; line-height: 1; letter-spacing: .011em; color: #86868b; }
.lede { font-family: var(--display); font-size: 21px; font-weight: 600; line-height: 1.381; letter-spacing: .011em; }
.hero-link { font-size: 17px; color: #2997ff; letter-spacing: -.022em; }
.hero-link:hover { text-decoration: underline; }
h2 { font-size: 56px; line-height: 1.07143; letter-spacing: -.005em; }
h2 em { color: #f5f5f7; }
.card .num { font-family: var(--display); color: #86868b; font-size: 17px; line-height: 1.23536; font-weight: 600; text-transform: none; letter-spacing: -.022em; margin-bottom: 20px; }
.card p { font-family: var(--display); font-size: 21px; font-weight: 600; line-height: 1.381; letter-spacing: .011em; color: #86868b; }
.card p.aside { font-family: var(--sans); font-size: 14px; font-weight: 400; line-height: 1.42859; letter-spacing: -.016em; border: none; padding: 0; color: #86868b; }
.control label, .control output, .stops button, #hud-fnum { font-variant-numeric: tabular-nums; }
.stops button { font-size: 14px; font-weight: 500; }
.stops button.active { background: #f5f5f7; border-color: #f5f5f7; }
#scene { opacity: 0; transition: opacity .5s; }
body[data-model-ready="true"] #scene { opacity: 1; }
.scene-status { position: fixed; z-index: 12; bottom: 12vh; left: 0; width: 100%; text-align: center; color: #a1a1a6; font-size: 13px; pointer-events: none; }
.scene-status[hidden] { display: none; }
section.intro { height: 300vh; }
.intro-inner { position: sticky; top: 0; height: 100vh; display: grid; place-items: center; }
.intro-copy { position: absolute; left: 6.25%; bottom: 18vh; width: min(560px, 80%); text-align: left; }
.intro-copy .eyebrow { color: #6e6e73; margin: 0 0 24px; }
.intro-copy h2 { font-size: 64px; line-height: 1.05; letter-spacing: -.015em; margin: 0; }
.intro-caption { position: absolute; bottom: 32px; left: 6.25%; right: 6.25%; display: flex; justify-content: space-between; gap: 24px; color: #86868b; font-size: 12px; }
.intro-caption a { pointer-events: auto; color: #d2d2d7; }
.intro-caption a:hover { text-decoration: underline; }
body[data-chapter="intro"] .chapter-nav { opacity: 0; pointer-events: none; }
@media (max-width: 1068px) {
  h1 { font-size: 64px; line-height: 1.0625; letter-spacing: -.009em; }
  h2 { font-size: 48px; line-height: 1.08349; letter-spacing: -.003em; }
  .intro-copy h2 { font-size: 56px; line-height: 1.05; }
  .card p { font-size: 19px; line-height: 1.4211; letter-spacing: .012em; }
}
@media (max-width: 734px) {
  .topbar { top: 8px; left: 12px; right: 12px; height: 52px; padding: 0 16px; border-radius: 22px; }
  .brand { font-size: 19px; letter-spacing: .012em; }
  .topbar nav > a:not(.nav-cta) { display: none; }
  .hero-inner { padding-top: 120px; }
  h1 { font-size: 48px; line-height: 1.08349; letter-spacing: -.003em; }
  .eyebrow { font-size: 17px; line-height: 1.23536; letter-spacing: -.022em; }
  .lede { font-size: 19px; line-height: 1.4211; letter-spacing: .012em; }
  .intro-copy { left: 24px; width: calc(100% - 48px); bottom: 16vh; }
  .intro-copy h2 { font-size: 56px; line-height: 1.07143; letter-spacing: -.005em; }
  .intro-copy .eyebrow { font-size: 19px; margin-bottom: 20px; }
  .intro-caption { bottom: 24px; left: 24px; right: 24px; align-items: flex-end; font-size: 11px; }
  .intro-caption > span { max-width: 140px; }
  .intro-caption a { max-width: 130px; text-align: right; }
  h2 { font-size: 40px; line-height: 1.1; letter-spacing: 0; }
  .card p { font-size: 17px; line-height: 1.47059; letter-spacing: -.022em; }
}
@media (prefers-reduced-motion: reduce) {
  section.intro { height: 100vh; }
}
body[data-chapter="intro"] .hud,
body[data-chapter="intro"] #labels { opacity: 0; visibility: hidden; }
@media (max-width: 734px) {
  .intro-copy h2 { font-size: 40px; line-height: 1.1; letter-spacing: normal; }
}

/* Copy lives behind the transparent 3D layer, never on a panel over the lens. */
#content { z-index: auto; }
#scene { z-index: 2; pointer-events: none; }
body.orbiting #scene { pointer-events: auto; }
.hero-inner, .intro-inner, .card { z-index: 1; }
#labels { z-index: 5; }
.card {
  background: transparent;
  border: 0;
  box-shadow: none;
  backdrop-filter: none;
  -webkit-backdrop-filter: none;
}
.card h2 { text-shadow: 0 2px 24px rgba(0, 0, 0, .3); }
.label b { background: rgba(14, 13, 16, .85); }
/* Keep the playground's controls above its orbit surface and keyboard usable. */
.play .card { z-index: 6; }
.outro { position: relative; z-index: 3; }

/* Let the macro aperture clear the reading area before the first explanation. */
#focus .card.on { opacity: var(--copy-reveal, 0); }
body[data-chapter="intro"] .card { opacity: 0; visibility: hidden; }
@media (max-width: 1000px) {
  #focus .card { margin-top: 115vh; }
}

/* The introductory headline must remain legible over the product close-up. */
.intro-inner { z-index: 3; }
.intro-copy h2 { text-shadow: 0 2px 28px rgba(0, 0, 0, .5); }

@media (max-width: 600px) {
  .brand { font-size: 14px; }
}

/* Keep the educational title and model caption readable over the phone. */
.hero-inner { z-index: 3; }

/* Asset loading covers the first render, including shader and texture warmup. */
.scene-status {
  inset: 0; z-index: 50; width: auto; background: #000;
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  gap: 18px; pointer-events: auto; opacity: 1; transition: opacity .35s ease;
}
.scene-status p { margin: 0; color: #f5f5f7; font-size: 17px; }
.scene-status > span { color: #86868b; font-size: 12px; font-variant-numeric: tabular-nums; }
.scene-status.is-ready { opacity: 0; pointer-events: none; }
.scene-status[hidden] { display: none; }
.loading-track { width: min(240px, 65vw); height: 3px; border-radius: 4px; overflow: hidden; background: #ffffff1f; }
.loading-track i { display: block; height: 100%; width: 100%; transform: scaleX(0); transform-origin: left; background: #dba7b4; transition: transform .2s ease; }
.diagram-backdrop { display: none; }
@media (max-width: 1000px) {
  .diagram-backdrop {
    display: block; position: fixed; z-index: 2; left: 0; right: 0;
    top: 0; height: 57vh; pointer-events: none;
    background: #000;
    backdrop-filter: blur(12px); -webkit-backdrop-filter: blur(12px);
    mask-image: linear-gradient(to bottom, #000 0%, #000 79%, transparent 100%);
    -webkit-mask-image: linear-gradient(to bottom, #000 0%, #000 79%, transparent 100%);
    opacity: 0; transition: opacity .35s ease;
  }
  body[data-model-ready="true"][data-chapter="focus"] .diagram-backdrop,
  body[data-model-ready="true"][data-chapter="blur"] .diagram-backdrop,
  body[data-model-ready="true"][data-chapter="close"] .diagram-backdrop,
  body[data-model-ready="true"][data-chapter="dof"] .diagram-backdrop,
  body[data-model-ready="true"][data-chapter="play"] .diagram-backdrop { opacity: 1; }
}

@media (max-width: 1000px) {
  /* Mobile controls scroll through the same fade as the other chapters. */
  .play .card { z-index: 1; }
  .play .drag-hint { display: none; }
  section.play { height: auto; min-height: 150vh; padding-bottom: 24vh; }
}

.sensor-hint {
  display: block; text-align: center; margin-top: 6px;
  font-size: 10px; line-height: 1.25; letter-spacing: 0; color: #c8c4c6;
  opacity: 0; visibility: hidden; transition: opacity .3s ease;
}
.sensor-view.on + .sensor-hint { opacity: 1; visibility: visible; }
@media (max-width: 1000px) {
  .hud { grid-template-areas: "f r1 sv" "f r2 sv" "f . hint"; }
  .sensor-hint { grid-area: hint; width: 0; max-height: 0; margin-top: 0; overflow: hidden; font-size: 9px; }
  .sensor-view.on + .sensor-hint { width: clamp(100px, 20vw, 144px); max-height: 30px; margin-top: 3px; }
}