/* ELYTRA SYSTEMS — site styles
   Palette: warm white / near black / technical gray / one restrained accent. */

:root {
  --bg: #F4F3EF;
  --bg-2: #EAE8E2;
  --sky: #E9E7E1;
  --ink: #111111;
  --gray: #777777;
  --gray-2: #B4B2AC;
  --rule: rgba(17, 17, 17, 0.16);
  --rule-2: rgba(17, 17, 17, 0.07);

  --dark: #111111;
  --dark-2: #191919;
  --on-dark: #ECEAE4;
  --gray-dark: #8C8A84;
  --rule-dark: rgba(236, 234, 228, 0.16);

  --accent: #E2B21C;

  --font: 'Geist', 'Helvetica Neue', Helvetica, Arial, sans-serif;
  --mono: 'Geist Mono', ui-monospace, 'SF Mono', Menlo, monospace;
  --pad: clamp(16px, 4vw, 56px);
  --gutter: clamp(12px, 1.6vw, 24px);
  --ease: cubic-bezier(0.2, 0.7, 0.2, 1);
}

*,
*::before,
*::after { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }
@media (prefers-reduced-motion: no-preference) { html { scroll-behavior: smooth; } }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font);
  font-size: 17px;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: clip;
}

h1, h2, h3, p, ol, ul, figure { margin: 0; }
ol, ul { padding: 0; list-style: none; }
a { color: inherit; text-decoration: none; }
button { font: inherit; color: inherit; }
img { display: block; max-width: 100%; }
::selection { background: var(--accent); color: var(--ink); }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; }

.wrap { width: 100%; max-width: 1680px; margin-inline: auto; padding-inline: var(--pad); }

/* ------------------------------------------------------------ type */
.label {
  font-family: var(--mono);
  font-size: 12px;
  font-weight: 400;
  letter-spacing: 0.08em;
  line-height: 1.5;
  text-transform: uppercase;
  color: var(--gray);
}
.display {
  font-size: clamp(42px, 9vw, 160px);
  line-height: 0.92;
  letter-spacing: -0.05em;
  font-weight: 500;
}
.statement {
  font-size: clamp(38px, 6.2vw, 108px);
  line-height: 0.98;
  letter-spacing: -0.045em;
  font-weight: 500;
  text-wrap: balance;
}
.h2 {
  font-size: clamp(30px, 3.8vw, 64px);
  line-height: 1.02;
  letter-spacing: -0.035em;
  font-weight: 500;
}
.h3 {
  font-size: clamp(26px, 2.8vw, 44px);
  line-height: 1.04;
  letter-spacing: -0.03em;
  font-weight: 500;
}
.lede {
  font-size: clamp(20px, 1.9vw, 28px);
  line-height: 1.3;
  letter-spacing: -0.015em;
}
.body-copy { color: #4a4a4a; max-width: 52ch; }
.muted { color: var(--gray); }
.dark .muted { color: var(--gray-dark); }
.dark .body-copy { color: var(--gray-dark); }

.dark { background: var(--dark); color: var(--on-dark); }
.dark .label { color: var(--gray-dark); }

.sec-head {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  border-top: 1px solid var(--rule);
  padding-top: 14px;
  margin-bottom: clamp(32px, 6vh, 72px);
}
.dark .sec-head { border-color: var(--rule-dark); }

/* measurement ticks: minor every 8px, major every 80px */
.ticks {
  height: 9px;
  border-top: 1px solid var(--rule);
  background-image:
    repeating-linear-gradient(90deg, var(--ink) 0 1px, transparent 1px 80px),
    repeating-linear-gradient(90deg, var(--rule) 0 1px, transparent 1px 8px);
  background-size: 100% 9px, 100% 4px;
  background-repeat: no-repeat;
}

/* ------------------------------------------------------------ buttons */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 14px;
  font-weight: 500;
  line-height: 1;
  border-radius: 2px;
  transition: background-color 0.3s, color 0.3s, border-color 0.3s;
}
.btn--outline { border: 1px solid currentColor; padding: 10px 14px; }
.btn--outline:hover { background: var(--ink); color: var(--bg); border-color: var(--ink); }
.btn--accent { background: var(--accent); color: var(--ink); padding: 18px 24px; font-size: 16px; }
.btn--accent:hover { background: var(--on-dark); }
.btn span { transition: transform 0.3s var(--ease); }
.btn:hover span { transform: translateX(3px); }

/* ------------------------------------------------------------ reveal-on-scroll */
.js [data-reveal] {
  opacity: 0;
  transform: translateY(22px);
  transition: opacity 1.1s var(--ease), transform 1.1s var(--ease);
}
.js [data-reveal].in { opacity: 1; transform: none; }

/* ------------------------------------------------------------ viewers */
.viewer { position: relative; }
.viewer canvas {
  display: block;
  width: 100%;
  height: 100%;
  opacity: 0;
  transition: opacity 1.4s var(--ease);
}
.viewer.is-ready canvas { opacity: 1; }
.no-webgl .viewer::after {
  content: attr(data-fallback);
  position: absolute;
  inset: 8%;
  display: grid;
  place-items: center;
  border: 1px dashed currentColor;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--gray);
  opacity: 0.7;
}

/* ------------------------------------------------------------ 01 nav */
.nav {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 50;
  height: 64px;
  display: flex;
  align-items: center;
  gap: 40px;
  padding-inline: var(--pad);
  border-bottom: 1px solid transparent;
  transition: background-color 0.45s, border-color 0.45s, color 0.45s;
}
.nav.is-solid {
  background: rgba(244, 243, 239, 0.78);
  -webkit-backdrop-filter: blur(16px) saturate(1.2);
  backdrop-filter: blur(16px) saturate(1.2);
  border-color: var(--rule);
}
.nav.is-dark { color: var(--on-dark); }
.nav.is-solid.is-dark { background: rgba(17, 17, 17, 0.72); border-color: var(--rule-dark); }
.nav__mark { font-size: 14px; font-weight: 600; letter-spacing: 0.28em; }
.nav__links { margin-left: auto; display: flex; gap: 32px; font-size: 14px; }
.nav__links a { position: relative; opacity: 0.85; transition: opacity 0.2s; }
.nav__links a:hover { opacity: 1; }
.nav__links a::after {
  content: '';
  position: absolute;
  left: 0; right: 0; bottom: -4px;
  height: 1px;
  background: currentColor;
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.35s var(--ease);
}
.nav__links a:hover::after { transform: scaleX(1); }
.nav__cta { padding: 9px 13px; font-size: 13px; }
.nav.is-dark .btn--outline:hover { background: var(--on-dark); color: var(--ink); border-color: var(--on-dark); }
.nav__toggle {
  display: none;
  margin-left: auto;
  background: none;
  border: 1px solid currentColor;
  border-radius: 2px;
  padding: 8px 12px;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  cursor: pointer;
}
.menu {
  position: fixed;
  inset: 64px 0 auto 0;
  z-index: 49;
  display: flex;
  flex-direction: column;
  padding: 8px var(--pad) 28px;
  background: var(--bg);
  border-bottom: 1px solid var(--rule);
}
.menu[hidden] { display: none; }
.menu a { font-size: 28px; letter-spacing: -0.02em; padding: 12px 0; border-top: 1px solid var(--rule); }

/* ------------------------------------------------------------ 02 hero */
.hero {
  position: relative;
  height: 100svh;
  min-height: 620px;
  display: flex;
  flex-direction: column;
  background: var(--sky);
}
.hero__stage { position: relative; flex: 1; overflow: hidden; }
.hero__viewer { position: absolute; inset: 0; }
.hero__veil {
  position: absolute;
  inset: 0 0 auto 0;
  height: 52%;
  background: linear-gradient(to bottom, rgba(233, 231, 225, 0.9) 20%, rgba(233, 231, 225, 0));
  pointer-events: none;
}
.hero__copy { position: absolute; left: 0; right: 0; top: calc(64px + 4.5vh); pointer-events: none; }
.hero__copy .label { margin-bottom: 22px; }
.hero__foot { background: var(--bg); padding-bottom: 20px; position: relative; z-index: 1; }
.hero__row {
  display: grid;
  grid-template-columns: minmax(0, 1.5fr) minmax(0, 1fr) auto;
  gap: 24px;
  align-items: end;
  padding-top: 18px;
}
.hero__sub { font-size: clamp(17px, 1.45vw, 22px); line-height: 1.35; letter-spacing: -0.01em; max-width: 38ch; }
.hero__scroll { color: var(--ink); }

.reticle {
  position: absolute;
  left: 0;
  top: 0;
  width: 0;
  height: 0;
  pointer-events: none;
  opacity: 0;
  transition: opacity 1s var(--ease) 0.8s;
  will-change: transform;
}
.reticle.is-on { opacity: 1; }
.reticle__c { position: absolute; width: 12px; height: 12px; border: 1px solid var(--ink); }
.reticle__c.c-tl { left: 0; top: 0; border-right: 0; border-bottom: 0; }
.reticle__c.c-tr { right: 0; top: 0; border-left: 0; border-bottom: 0; }
.reticle__c.c-bl { left: 0; bottom: 0; border-right: 0; border-top: 0; }
.reticle__c.c-br { right: 0; bottom: 0; border-left: 0; border-top: 0; }
.reticle__tag {
  position: absolute;
  left: 100%;
  top: 0;
  transform: translate(10px, -2px);
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  line-height: 1.4;
  white-space: nowrap;
  padding-left: 8px;
  border-left: 1px solid var(--accent);
}
.reticle__tag em { display: block; font-style: normal; color: var(--gray); }

/* ------------------------------------------------------------ 03 thesis */
.thesis { padding: 30vh 0 24vh; }
.thesis__body {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: var(--gutter);
  margin-top: clamp(56px, 12vh, 140px);
}
.thesis__body .lede { grid-column: 1 / span 6; }
.thesis__body .body-copy { grid-column: 8 / span 5; }

/* ------------------------------------------------------------ 04 platform */
.platform { padding: 18vh 0 10vh; overflow: hidden; }
.platform__stage { position: relative; height: min(86vh, 60vw); min-height: 480px; margin-top: 2vh; }
.platform__viewer { position: absolute; inset: 0; }
.leaders {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  overflow: visible;
}
.leaders path {
  fill: none;
  stroke: rgba(236, 234, 228, 0.55);
  stroke-width: 1;
  stroke-dasharray: 1;
  stroke-dashoffset: 1;
  transition: stroke-dashoffset 1.4s var(--ease);
}
.leaders circle { fill: var(--dark); stroke: var(--accent); stroke-width: 1; opacity: 0; transition: opacity 0.6s 0.9s; }
.leaders circle.pip { fill: var(--accent); stroke: none; }
.is-drawn .leaders path { stroke-dashoffset: 0; }
.is-drawn .leaders circle { opacity: 1; }

.callouts { position: absolute; inset: 0; padding-inline: var(--pad); pointer-events: none; }
.callout {
  position: absolute;
  left: var(--x);
  top: var(--y);
  display: grid;
  gap: 3px;
  width: max-content;
  max-width: 220px;
  opacity: 0;
  transform: translateY(8px);
  transition: opacity 0.9s var(--ease), transform 0.9s var(--ease);
}
.is-drawn .callout { opacity: 1; transform: none; }
.callout__n { font-family: var(--mono); font-size: 11px; color: var(--accent); letter-spacing: 0.08em; }
.callout__t { font-family: var(--mono); font-size: 13px; letter-spacing: 0.08em; }
.callout__d { font-size: 14px; color: var(--gray-dark); }
.platform__fig { position: absolute; left: var(--pad); bottom: 0; }

/* ------------------------------------------------------------ 05 reveal */
.reveal__track { height: 520vh; position: relative; }
.reveal__pin { position: sticky; top: 0; height: 100svh; overflow: hidden; }
.reveal__viewer { position: absolute; inset: 0; }
.reveal__ui {
  position: relative;
  height: 100%;
  display: grid;
  grid-template-columns: minmax(260px, 380px) 1fr;
  grid-template-rows: auto 1fr auto;
  padding-top: 104px;
  padding-bottom: 28px;
  pointer-events: none;
}
.reveal__pin::after {
  /* keeps copy legible when close-up geometry passes behind it */
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(100deg, rgba(17, 17, 17, 0.88) 0%, rgba(17, 17, 17, 0.55) 26%, rgba(17, 17, 17, 0) 46%);
  pointer-events: none;
}
.reveal__ui { z-index: 1; }
.reveal__head { grid-column: 1 / -1; }
.reveal__head .label { margin-bottom: 18px; }
.layers { grid-column: 1; align-self: center; }
.layer {
  display: grid;
  grid-template-columns: 40px 1fr;
  padding: 14px 0;
  border-top: 1px solid var(--rule-dark);
  color: var(--gray-dark);
  transition: color 0.5s;
}
.layer__n { font-family: var(--mono); font-size: 12px; padding-top: 4px; transition: color 0.5s; }
.layer__t { font-size: 22px; letter-spacing: -0.02em; }
.layer p {
  grid-column: 2;
  font-size: 15px;
  line-height: 1.45;
  max-height: 0;
  opacity: 0;
  overflow: hidden;
  transition: max-height 0.6s var(--ease), opacity 0.6s, margin 0.6s;
}
.layer.is-active { color: var(--on-dark); }
.layer.is-active .layer__n { color: var(--accent); }
.layer.is-active p { max-height: 120px; opacity: 1; margin-top: 8px; color: var(--gray-dark); }
.reveal__rail { grid-column: 1 / -1; display: grid; gap: 12px; }
.reveal__bar { height: 1px; background: var(--rule-dark); position: relative; }
.reveal__bar span { position: absolute; left: 0; top: -0.5px; height: 2px; width: 0; background: var(--accent); }

/* ------------------------------------------------------------ placeholders */
.ph {
  position: relative;
  aspect-ratio: var(--ar, 4 / 3);
  overflow: hidden;
  background-color: var(--bg-2);
  background-image:
    linear-gradient(to top right, transparent calc(50% - 0.5px), var(--rule-2) 50%, transparent calc(50% + 0.5px)),
    linear-gradient(to bottom right, transparent calc(50% - 0.5px), var(--rule-2) 50%, transparent calc(50% + 0.5px));
}
.ph__label {
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  max-width: 82%;
  padding: 6px 10px;
  background: var(--bg-2);
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  line-height: 1.45;
  text-transform: uppercase;
  text-align: center;
  color: var(--gray);
  z-index: 1;
}
.ph figcaption {
  position: absolute;
  left: 12px;
  bottom: 10px;
  font-family: var(--mono);
  font-size: 10.5px;
  letter-spacing: 0.08em;
  color: var(--gray);
  z-index: 1;
}
.ph__c { position: absolute; width: 10px; height: 10px; border: 1px solid var(--gray-2); z-index: 1; }
.ph__c.c-tl { left: 8px; top: 8px; border-right: 0; border-bottom: 0; }
.ph__c.c-tr { right: 8px; top: 8px; border-left: 0; border-bottom: 0; }
.ph__c.c-bl { left: 8px; bottom: 8px; border-right: 0; border-top: 0; }
.ph__c.c-br { right: 8px; bottom: 8px; border-left: 0; border-top: 0; }
.ph > img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0;
  transform: scale(1.03);
  transition: opacity 1.4s var(--ease), transform 2.4s var(--ease);
}
.ph > img.is-loaded { opacity: 1; transform: none; }
.ph.has-img .ph__c { display: none; }
.ph.has-img .ph__label {
  left: auto;
  top: auto;
  right: 10px;
  bottom: 10px;
  transform: none;
  max-width: 60%;
  font-size: 10px;
  padding: 4px 8px;
  background: rgba(17, 17, 17, 0.55);
  color: rgba(244, 243, 239, 0.85);
  text-align: right;
}
.dark .ph { background-color: var(--dark-2); }

/* ------------------------------------------------------------ 06 problem */
.problem { padding: 22vh 0 20vh; }
.probs { display: grid; gap: clamp(64px, 12vh, 140px); margin-top: clamp(64px, 12vh, 140px); }
.prob {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: var(--gutter);
  align-items: end;
  border-top: 1px solid var(--rule);
  padding-top: 20px;
}
.prob__text { grid-column: 1 / span 4; align-self: start; display: grid; gap: 20px; }
.prob .ph { grid-column: 5 / -1; }
.prob:nth-child(2) .prob__text { grid-column: 9 / -1; grid-row: 1; }
.prob:nth-child(2) .ph { grid-column: 1 / span 8; grid-row: 1; }
.turn {
  margin-top: clamp(96px, 20vh, 220px);
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
  gap: 24px;
}
.turn__arrow { font-size: clamp(38px, 6.2vw, 108px); line-height: 1; color: var(--accent); }

/* ------------------------------------------------------------ 07 why helium */
.helium__track { height: 380vh; position: relative; }
.helium__pin {
  position: sticky;
  top: 0;
  height: 100svh;
  display: grid;
  grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
  overflow: hidden;
}
.helium__copy { align-self: center; padding-top: 64px; max-width: none; }
.helium__copy .label { margin-bottom: 22px; }
.helium .statement { font-size: clamp(36px, 5vw, 92px); }
.chain { margin-top: clamp(32px, 6vh, 64px); counter-reset: chain; }
.chain li {
  display: grid;
  grid-template-columns: 36px 1fr;
  padding: 14px 0;
  border-top: 1px solid var(--rule-dark);
  font-size: clamp(17px, 1.4vw, 21px);
  letter-spacing: -0.01em;
  opacity: 0.22;
  transition: opacity 0.7s var(--ease);
}
.chain li::before { content: '—'; font-family: var(--mono); font-size: 13px; color: var(--gray-dark); padding-top: 3px; }
.chain li + li::before { content: '↓'; }
.chain li.is-on { opacity: 1; }
.chain li.is-on::before { color: var(--accent); }
.helium__stage { position: relative; }
.helium__viewer { position: absolute; inset: 0; }
.helium .leaders path { stroke-dasharray: none; stroke-dashoffset: 0; stroke: rgba(236, 234, 228, 0.4); }
.helium .leaders circle { opacity: 1; transition: none; }
.tags { position: absolute; inset: 0; pointer-events: none; }
.tag {
  position: absolute;
  left: 0;
  top: 0;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  white-space: nowrap;
  color: var(--on-dark);
  opacity: 0;
  will-change: transform, opacity;
}
.helium__fig { position: absolute; right: var(--pad); bottom: 28px; }

/* ------------------------------------------------------------ 08 quiet */
.quiet { padding: 28vh 0 20vh; }
.quiet__grid {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: var(--gutter);
  margin-top: clamp(64px, 14vh, 160px);
}
.quiet__stage { grid-column: 1 / span 7; position: relative; aspect-ratio: 5 / 4; background: var(--bg-2); }
.quiet__viewer { position: absolute; inset: 0; }
.quiet__fig { position: absolute; left: 14px; bottom: 12px; }
.quiet__side { grid-column: 9 / -1; display: flex; flex-direction: column; justify-content: center; gap: 40px; }
.flow li {
  display: flex;
  align-items: baseline;
  gap: 16px;
  padding: 14px 0;
  border-top: 1px solid var(--rule);
  font-size: clamp(18px, 1.5vw, 22px);
  letter-spacing: -0.015em;
}
.flow li:not(:last-child)::after { content: '↓'; margin-left: auto; color: var(--gray); font-size: 15px; }
.data-ph { display: grid; gap: 10px; }
.data-ph svg { width: 100%; height: auto; }
.data-ph line { stroke: var(--rule); stroke-width: 1; vector-effect: non-scaling-stroke; }
.data-ph line:nth-child(n+3) { stroke-dasharray: 2 4; }
.data-ph figcaption { display: grid; gap: 4px; font-size: 14px; color: var(--gray); }

/* ------------------------------------------------------------ 09 safety */
.safety { padding: 20vh 0; }
.plan {
  display: grid;
  grid-template-columns: minmax(0, 3fr) minmax(220px, 1fr);
  gap: clamp(24px, 4vw, 64px);
  align-items: center;
  margin-top: clamp(48px, 10vh, 120px);
}
.plan__svg { width: 100%; height: auto; display: block; }
.p-grid { stroke: rgba(236, 234, 228, 0.05); stroke-width: 1; }
.p-hatch { stroke: rgba(236, 234, 228, 0.13); stroke-width: 1; }
.p-stands { fill: url(#hatch); stroke: rgba(236, 234, 228, 0.4); stroke-width: 1; }
.p-rows rect { fill: none; stroke: rgba(236, 234, 228, 0.08); }
.p-field { fill: rgba(236, 234, 228, 0.03); stroke: rgba(236, 234, 228, 0.7); }
.p-ez { fill: rgba(236, 234, 228, 0.07); stroke: rgba(236, 234, 228, 0.7); }
.p-yard line { stroke: rgba(236, 234, 228, 0.18); }
.p-volume { fill: rgba(226, 178, 28, 0.05); stroke: var(--accent); stroke-dasharray: 6 5; }
.p-tlz rect, .p-tlz path { fill: none; stroke: var(--on-dark); }
.p-op rect, .p-op path { fill: none; stroke: var(--on-dark); }
.p-emerg { fill: none; stroke: var(--accent); stroke-dasharray: 2 4; stroke-width: 1.5; }
.p-arrow { fill: var(--accent); }
.p-craft ellipse { fill: var(--on-dark); }
.p-craft circle { fill: var(--dark); stroke: var(--on-dark); }
.p-txt text { fill: var(--gray-dark); font-family: var(--mono); font-size: 9.5px; letter-spacing: 0.08em; }
.p-mk circle { fill: var(--dark); stroke: rgba(236, 234, 228, 0.6); }
.p-mk text { fill: var(--on-dark); font-family: var(--mono); font-size: 10px; text-anchor: middle; letter-spacing: 0.04em; }
.legend li {
  display: grid;
  grid-template-columns: 40px 1fr;
  padding: 11px 0;
  border-top: 1px solid var(--rule-dark);
  font-size: 15px;
}
.legend span { font-family: var(--mono); font-size: 12px; color: var(--gray-dark); padding-top: 2px; }
.legend span.is-accent { color: var(--accent); }
.legend em { grid-column: 2; font-style: normal; font-size: 13px; color: var(--gray-dark); }
.arch {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: var(--gutter);
  margin-top: clamp(80px, 16vh, 180px);
}
.arch h3 { grid-column: 1 / span 6; }
.arch__body { grid-column: 8 / -1; }
.systems li {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 16px;
  padding: 12px 0;
  border-top: 1px solid var(--rule-dark);
  font-size: 17px;
}
.systems li::after {
  content: 'IN DEVELOPMENT';
  font-family: var(--mono);
  font-size: 10.5px;
  letter-spacing: 0.08em;
  color: var(--gray-dark);
  white-space: nowrap;
}
.note { margin-top: 32px; font-size: 14px; color: var(--gray-dark); max-width: 56ch; }
.dark .note .label { display: block; margin-bottom: 6px; color: var(--accent); }

/* ------------------------------------------------------------ 10 camera */
.camera { padding: 22vh 0 14vh; }
.feed-wrap { margin-top: 2vh; }
.feed { position: relative; }
.feed__hud {
  position: absolute;
  inset: 0;
  pointer-events: none;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--gray);
  z-index: 2;
}
.feed.has-still .feed__hud { color: rgba(255, 255, 255, 0.92); text-shadow: 0 1px 2px rgba(0, 0, 0, 0.3); }
.feed__hud > span { position: absolute; }
.feed__tl { left: 3%; top: 4%; }
.feed__tr { right: 3%; top: 4%; display: flex; align-items: center; gap: 8px; }
.feed__tr i { width: 8px; height: 8px; background: var(--accent); }
.feed__bl { left: 3%; bottom: 4%; font-variant-numeric: tabular-nums; }
.feed__br { right: 3%; bottom: 4%; opacity: 0.75; }
.feed__safe { position: absolute; inset: 9% 6%; border: 1px dashed currentColor; opacity: 0.25; }
.feed .ph.has-img .ph__label { display: none; }
.modes {
  display: flex;
  flex-wrap: wrap;
  column-gap: clamp(16px, 3vw, 56px);
  margin-top: 40px;
  border-top: 1px solid var(--rule);
}
.mode {
  position: relative;
  background: none;
  border: 0;
  padding: 18px 0 0;
  cursor: pointer;
  font-size: clamp(24px, 3.4vw, 56px);
  font-weight: 500;
  letter-spacing: -0.035em;
  line-height: 1;
  color: var(--gray-2);
  transition: color 0.35s;
}
.mode:hover { color: var(--gray); }
.mode.is-active { color: var(--ink); }
.mode::before {
  content: '';
  position: absolute;
  left: 0;
  top: -1px;
  height: 2px;
  width: 100%;
  background: var(--accent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.5s var(--ease);
}
.mode.is-active::before { transform: scaleX(1); }
.mode-desc { margin-top: 20px; color: var(--gray); font-size: 17px; min-height: 1.5em; }

/* ------------------------------------------------------------ 11 apps */
.apps { padding: 18vh 0 20vh; }
.apps__grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: clamp(48px, 8vh, 96px) var(--gutter);
  margin-top: clamp(56px, 10vh, 120px);
}
.app:nth-child(even) { margin-top: clamp(40px, 14vh, 180px); }
.app__t { margin-top: 20px; font-size: clamp(20px, 1.7vw, 26px); font-weight: 500; letter-spacing: 0.04em; }
.app__d { color: var(--gray); margin-top: 4px; }

/* ------------------------------------------------------------ 12 college football */
.cfb { padding: 16vh 0 20vh; }
.cfb__head { display: flex; justify-content: space-between; align-items: flex-end; gap: 24px 48px; flex-wrap: wrap; }
.cfb__head .lede { color: var(--gray); }
.cfb__img { margin: clamp(48px, 9vh, 110px) 0; }
.cfb__stmts {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--gutter);
}
.cfb__stmts li {
  display: flex;
  gap: 14px;
  align-items: baseline;
  padding-top: 16px;
  border-top: 1px solid var(--ink);
  font-family: var(--mono);
  font-size: 14px;
  letter-spacing: 0.08em;
}
.cfb__long { margin-top: clamp(80px, 16vh, 180px); }

/* ------------------------------------------------------------ 13 how it works */
.how__track { height: 260vh; position: relative; }
.how__pin { position: sticky; top: 0; height: 100svh; display: flex; align-items: center; padding-top: 64px; }
.how__title { margin-bottom: clamp(40px, 9vh, 100px); }
.seq { position: relative; }
.seq__line { position: absolute; left: 0; right: 0; top: 0; height: 1px; background: var(--rule); }
.seq__line span { position: absolute; left: 0; top: 0; height: 1px; width: 0; background: var(--ink); }
.seq ol { display: grid; grid-template-columns: repeat(6, minmax(0, 1fr)); gap: var(--gutter); }
.stage {
  position: relative;
  padding-top: 28px;
  opacity: 0.22;
  transform: translateY(10px);
  transition: opacity 0.7s var(--ease), transform 0.7s var(--ease);
}
.stage::before { content: ''; position: absolute; left: 0; top: -4px; width: 1px; height: 9px; background: var(--ink); }
.stage.is-on { opacity: 1; transform: none; }
.stage svg {
  display: block;
  width: 100%;
  max-width: 170px;
  height: auto;
  margin-bottom: 22px;
  fill: none;
  stroke: var(--ink);
  stroke-width: 1.25;
  stroke-linecap: round;
  stroke-linejoin: round;
}
.stage svg .thin { stroke-width: 0.8; stroke: var(--gray); }
.stage svg .acc { stroke: var(--accent); }
.stage svg rect.acc { fill: var(--accent); stroke: none; }
.stage:not(:last-child) .label::after { content: '  →'; }
.stage h3 { margin: 6px 0 4px; font-size: 17px; font-weight: 500; letter-spacing: 0.07em; }
.stage p { color: var(--gray); font-size: 15px; }

/* ------------------------------------------------------------ 14 engineering */
.eng { padding: 16vh 0 18vh; }
.collage {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: var(--gutter);
  align-items: start;
  margin-top: clamp(56px, 10vh, 120px);
}
.c-cad { grid-column: 1 / span 8; --ar: 16 / 10; }
.c-proto { grid-column: 9 / span 4; --ar: 4 / 5; margin-top: 14vh; }
.c-elec { grid-column: 2 / span 4; --ar: 4 / 3; }
.c-carbon { grid-column: 6 / span 3; --ar: 1 / 1; margin-top: 12vh; }
.c-print { grid-column: 9 / span 3; --ar: 3 / 4; margin-top: 4vh; }
.c-flight { grid-column: 1 / span 10; --ar: 21 / 9; margin-top: 6vh; }
.c-team { grid-column: 7 / span 6; --ar: 3 / 2; margin-top: 2vh; }

/* ------------------------------------------------------------ 15 timeline */
.timeline { padding: 14vh 0 18vh; }
.tl {
  margin-top: clamp(48px, 9vh, 110px);
  overflow-x: auto;
  scrollbar-width: thin;
  max-width: 1680px;
  margin-inline: auto;
  padding: 0 var(--pad) 12px;
}
.tl__list {
  position: relative;
  display: grid;
  grid-template-columns: repeat(7, minmax(150px, 1fr));
  gap: var(--gutter);
}
.tl__list::before { content: ''; position: absolute; left: 0; right: 0; top: 5px; height: 1px; background: var(--rule); }
.tl__dot {
  position: relative;
  display: block;
  width: 11px;
  height: 11px;
  margin-bottom: 20px;
  border: 1px solid var(--ink);
  border-radius: 50%;
  background: var(--bg);
}
.tl__list li.is-done .tl__dot { background: var(--ink); }
.tl__list li.is-current .tl__dot { background: var(--accent); border-color: var(--accent); }
.tl__list h3 { margin: 6px 0 16px; min-height: 3em; line-height: 1.5; font-size: 15px; font-weight: 500; letter-spacing: 0.07em; }
.tl__list li:not(:last-child) .label::after { content: '  →'; color: var(--gray-2); }

/* ------------------------------------------------------------ 16 big statement */
.big__track { height: 330vh; position: relative; }
.big__pin { position: sticky; top: 0; height: 100svh; overflow: hidden; }
.big__text { position: relative; z-index: 1; padding-top: calc(64px + 12vh); }
.big .display { font-size: clamp(38px, 7.2vw, 136px); max-width: 15ch; }
.big__l1, .big__l2 { opacity: 0; transform: translateY(24px); transition: opacity 1.2s var(--ease), transform 1.2s var(--ease); }
.big__l2 { margin-top: 0.25em; }
.big__l1.is-on, .big__l2.is-on { opacity: 1; transform: none; }
.big__viewer {
  position: absolute;
  inset: 28% 0 0 0;
  opacity: 0;
  transform: translateY(6%) scale(0.94);
  transition: opacity 1.6s var(--ease), transform 2s var(--ease);
}
.big__viewer.is-on { opacity: 1; transform: none; }

/* ------------------------------------------------------------ 17 contact */
.contact { padding: 22vh 0 18vh; }
.contact__grid {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: var(--gutter);
  margin-top: clamp(56px, 11vh, 130px);
}
.who { grid-column: 1 / span 6; }
.who li {
  padding: 14px 0;
  border-top: 1px solid var(--rule-dark);
  font-size: clamp(24px, 2.6vw, 40px);
  letter-spacing: -0.03em;
  line-height: 1.1;
}
.contact__cta { grid-column: 8 / -1; align-self: end; display: flex; flex-direction: column; align-items: flex-start; gap: 20px; }
.contact__mail { font-family: var(--mono); font-size: 14px; letter-spacing: 0.04em; color: var(--gray-dark); }
.contact__mail:hover { color: var(--on-dark); }

/* ------------------------------------------------------------ 18 footer */
.footer { padding: 40px 0 32px; }
.footer__grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 32px;
  padding-top: 32px;
}
.footer__mark { font-size: 14px; font-weight: 600; letter-spacing: 0.24em; }
.footer__tag { color: var(--gray); margin-top: 8px; }
.footer__links { display: flex; flex-direction: column; gap: 6px; font-size: 15px; }
.footer__links a:hover { color: var(--gray); }
.footer__meta { display: grid; gap: 6px; align-content: start; }

/* ------------------------------------------------------------ responsive */
@media (max-width: 1100px) {
  .reveal__ui { grid-template-columns: minmax(240px, 320px) 1fr; }
  .callout { max-width: 180px; }
}

@media (max-width: 900px) {
  .hero__row { grid-template-columns: 1fr auto; }
  .hero__meta { display: none; }
  .thesis__body .lede, .thesis__body .body-copy { grid-column: 1 / -1; }

  .platform__stage { height: auto; min-height: 0; display: grid; }
  .platform__viewer { position: relative; inset: auto; aspect-ratio: 4 / 3; }
  .platform .leaders { display: none; }
  .callouts { position: static; display: grid; grid-template-columns: 1fr 1fr; gap: 20px var(--gutter); padding-top: 24px; }
  .callout { position: static; max-width: none; padding-top: 12px; border-top: 1px solid var(--rule-dark); }
  .platform__fig { position: static; padding: 24px var(--pad) 0; }

  .reveal__ui { grid-template-columns: 1fr; grid-template-rows: auto 1fr auto auto; padding-top: 88px; }
  .layers { grid-row: 3; align-self: end; background: linear-gradient(to top, rgba(17, 17, 17, 0.92) 70%, rgba(17, 17, 17, 0)); padding-top: 32px; }
  .layer { padding: 10px 0; }
  .layer__t { font-size: 18px; }
  .layer:not(.is-active) { display: none; }
  .reveal__rail { grid-row: 4; padding-top: 14px; }
  .reveal__rail .label { font-size: 10px; }

  .prob__text, .prob:nth-child(2) .prob__text { grid-column: 1 / -1; grid-row: 1; }
  .prob .ph, .prob:nth-child(2) .ph { grid-column: 1 / -1; grid-row: 2; }

  .helium__pin { grid-template-columns: 1fr; grid-template-rows: auto 1fr; }
  .helium__copy { padding-top: 84px; }
  .helium .statement { font-size: clamp(32px, 9vw, 56px); }
  .chain { margin-top: 18px; }
  .chain li { padding: 8px 0; font-size: 15px; }
  .tags .tag { font-size: 9.5px; }
  .helium__fig { display: none; }

  .quiet__stage, .quiet__side { grid-column: 1 / -1; }

  .plan { grid-template-columns: 1fr; }
  .arch h3, .arch__body { grid-column: 1 / -1; }
  .arch__body { margin-top: 32px; }

  .apps__grid { grid-template-columns: 1fr; }
  .app:nth-child(even) { margin-top: 0; }

  .cfb__stmts { grid-template-columns: 1fr; }

  .how__track { height: auto; }
  .how__pin { position: static; height: auto; padding: 16vh 0; }
  .seq ol { grid-template-columns: repeat(2, minmax(0, 1fr)); row-gap: 48px; }
  .seq__line { display: none; }
  .stage { border-top: 1px solid var(--rule); }
  .stage::before { display: none; }

  .collage { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .collage .ph { grid-column: auto / span 1; margin-top: 0; }
  .c-cad, .c-flight { grid-column: 1 / -1 !important; }
  .c-team { grid-column: 1 / -1 !important; }

  .contact__grid > * { grid-column: 1 / -1; }
  .contact__cta { margin-top: 40px; }

  .footer__grid { grid-template-columns: 1fr 1fr; }
  .footer__grid > div:first-child { grid-column: 1 / -1; }
}

@media (max-width: 760px) {
  .nav { height: 56px; }
  .nav__links, .nav__cta { display: none; }
  .nav__toggle { display: inline-block; }
  .menu { inset: 56px 0 auto 0; }
  .hero__copy { top: calc(56px + 3vh); }
  .hero__copy .label { margin-bottom: 14px; font-size: 10.5px; }
  .sec-head .label + .label { display: none; }
  .callouts { grid-template-columns: 1fr; }
  .callout { width: auto; }
  .reticle__tag { left: 0; top: 0; transform: translateY(calc(-100% - 8px)); }
  .turn { flex-direction: column; align-items: flex-start; }
}

@media (prefers-reduced-motion: reduce) {
  .js [data-reveal], .stage, .chain li, .big__l1, .big__l2, .big__viewer, .callout, .reticle {
    transition: none !important;
  }
  .leaders path { transition: none; }
}