/* ============================================================
   GREY NEURAL AI
   Monochrome-first. The name is the concept: grey matter.
   Colour is signal, never decoration. Product hues appear only
   inside their own product cards, so products sit visibly
   *under* the umbrella brand.

   Radius scale: pills 999px · panels 18px · insets 12px
   ============================================================ */

:root {
  --void: #08080a;
  --graphite: #131316;
  --graphite-2: #1b1b20;
  --graphite-3: #24242b;

  --line: rgba(255, 255, 255, 0.08);
  --line-2: rgba(255, 255, 255, 0.16);

  --ink: #f4f4f5;
  --matter: #949496;          /* the logo grey — primary brand tone */
  --muted: #a2a2a8;
  --faint: #6b6b74;

  --signal: linear-gradient(180deg, #ffffff 0%, #e2e2e7 58%, #b9b9c1 100%);
  --edge: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.34), transparent);

  /* product accents — scoped to product cards only */
  --jee: #4ade80;
  --jee-2: #d9b44a;
  --neet: #2dd4bf;
  --neet-2: #fb7185;
  --pyq: #a9a9b2;

  --r: 18px;
  --r-sm: 12px;
  --maxw: 1180px;
  --ease: cubic-bezier(0.16, 1, 0.3, 1);
  --nav-h: 68px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html {
  -webkit-text-size-adjust: 100%;
  background: var(--void);
  scrollbar-color: var(--graphite-3) var(--void);
}

body {
  background: var(--void);
  color: var(--ink);
  font-family: "Jost", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-size: 17px;
  line-height: 1.62;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

body.menu-open { overflow: hidden; }

img, svg, canvas { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
::selection { background: rgba(255, 255, 255, 0.18); color: #fff; }

:focus-visible {
  outline: 2px solid var(--ink);
  outline-offset: 3px;
  border-radius: 4px;
}

/* ---------- type ---------- */
h1, h2, h3, .line-xl { font-weight: 600; letter-spacing: -0.028em; line-height: 1.06; }
/* .line-xl is a scroll beat, not a document heading — same look, no outline weight */
h1, .line-xl { font-size: clamp(2.9rem, 7.4vw, 6.4rem); }
h2 { font-size: clamp(2.1rem, 4.6vw, 3.9rem); }
h3 { font-size: clamp(1.16rem, 1.7vw, 1.4rem); letter-spacing: -0.018em; line-height: 1.24; }

.mono {
  font-family: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: 0.7rem;
  letter-spacing: 0.19em;
  text-transform: uppercase;
  font-weight: 500;
}

.kicker { color: var(--faint); display: inline-block; }
.kicker::before {
  content: "";
  display: inline-block;
  width: 22px;
  height: 1px;
  background: var(--matter);
  vertical-align: middle;
  margin-right: 12px;
}

.grad { background: var(--signal); -webkit-background-clip: text; background-clip: text; color: transparent; }
.dim { color: var(--matter); }
.lead { font-size: clamp(1.04rem, 1.5vw, 1.22rem); color: var(--muted); max-width: 60ch; }

.container { width: 100%; max-width: var(--maxw); margin: 0 auto; padding: 0 28px; }
.section { padding: clamp(6rem, 13vh, 10rem) 0; position: relative; }
.section-head { max-width: 66ch; }
.section-head h2 { margin-top: 1.1rem; }
.section-head .lead { margin-top: 1.3rem; }

/* ============================================================
   Preloader
   ============================================================ */
#preloader {
  position: fixed;
  inset: 0;
  z-index: 999;
  background: var(--void);
  display: grid;
  place-items: center;
  transition: opacity 0.8s var(--ease), visibility 0.8s;
}
#preloader.done { opacity: 0; visibility: hidden; }
.pre-mark {
  width: 74px;
  color: var(--matter);
  animation: breathe 2.1s var(--ease) infinite;
}
.pre-bar {
  width: 132px;
  height: 1px;
  background: var(--line-2);
  margin: 26px auto 0;
  overflow: hidden;
}
.pre-bar::after {
  content: "";
  display: block;
  height: 100%;
  width: 40%;
  background: var(--ink);
  animation: sweep 1.25s var(--ease) infinite;
}
@keyframes breathe { 0%, 100% { opacity: 0.45; transform: scale(0.97); } 50% { opacity: 1; transform: scale(1); } }
@keyframes sweep { 0% { transform: translateX(-100%); } 100% { transform: translateX(330%); } }

/* ============================================================
   Nav
   ============================================================ */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-h);
  z-index: 200;
  display: flex;
  align-items: center;
  transition: background 0.4s var(--ease), border-color 0.4s var(--ease), backdrop-filter 0.4s;
  border-bottom: 1px solid transparent;
}
.nav.solid {
  background: rgba(8, 8, 10, 0.72);
  backdrop-filter: saturate(160%) blur(16px);
  -webkit-backdrop-filter: saturate(160%) blur(16px);
  border-bottom-color: var(--line);
}
.nav-inner {
  width: 100%;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 28px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}
.brand { display: flex; align-items: center; gap: 11px; }
.brand-mark { width: 27px; color: var(--matter); transition: color 0.35s var(--ease); }
.brand:hover .brand-mark { color: var(--ink); }
/* tracked out to match the wordmark in the logo lockup */
.brand-text {
  font-size: 0.92rem;
  font-weight: 500;
  letter-spacing: 0.17em;
  white-space: nowrap;
}
.brand-text b { font-weight: 500; color: var(--ink); }
.brand-text span { color: var(--matter); font-weight: 300; }

.nav-links { display: flex; gap: 30px; align-items: center; }
.nav-links a {
  font-size: 0.87rem;
  color: var(--muted);
  transition: color 0.28s var(--ease);
  position: relative;
}
.nav-links a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -5px;
  height: 1px;
  width: 0;
  background: var(--ink);
  transition: width 0.34s var(--ease);
}
.nav-links a:hover { color: var(--ink); }
.nav-links a:hover::after { width: 100%; }

.nav-burger {
  display: none;
  background: none;
  border: 1px solid var(--line-2);
  border-radius: 999px;
  color: var(--ink);
  width: 40px;
  height: 40px;
  cursor: pointer;
  align-items: center;
  justify-content: center;
}
.nav-burger span { width: 15px; height: 9px; position: relative; display: block; }
.nav-burger span::before,
.nav-burger span::after {
  content: "";
  position: absolute;
  left: 0;
  width: 100%;
  height: 1.5px;
  background: currentColor;
  transition: transform 0.34s var(--ease);
}
.nav-burger span::before { top: 0; }
.nav-burger span::after { bottom: 0; }
body.menu-open .nav-burger span::before { transform: translateY(4px) rotate(45deg); }
body.menu-open .nav-burger span::after { transform: translateY(-3.5px) rotate(-45deg); }

#scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  height: 2px;
  width: 100%;
  background: var(--ink);
  transform: scaleX(0);
  transform-origin: 0 50%;
  z-index: 210;
  will-change: transform;
}

/* ---------- buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 0.82rem 1.5rem;
  border-radius: 999px;
  font-size: 0.9rem;
  font-weight: 500;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform 0.34s var(--ease), background 0.34s var(--ease),
              border-color 0.34s var(--ease), color 0.34s var(--ease);
  white-space: nowrap;
}
.btn-primary { background: var(--ink); color: var(--void); }
.btn-primary:hover { transform: translateY(-2px); background: #fff; }
.btn-ghost { border-color: var(--line-2); color: var(--ink); }
.btn-ghost:hover { border-color: var(--ink); background: rgba(255, 255, 255, 0.05); transform: translateY(-2px); }
.btn-sm { padding: 0.6rem 1.15rem; font-size: 0.84rem; }
.btn-group { display: flex; flex-wrap: wrap; gap: 13px; }

/* ============================================================
   Cinematic scrub sections
   ============================================================ */
.cinematic { position: relative; background: var(--void); }
.cinematic .sticky {
  position: sticky;
  top: 0;
  height: 100vh;
  height: 100svh;
  overflow: hidden;
}
.cinematic canvas { width: 100%; height: 100%; display: block; }

#hero { height: 520vh; }
#engine-scrub { height: 460vh; }
#ecosystem-scrub { height: 420vh; }

.overlay {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  text-align: center;
  padding: 0 28px;
  pointer-events: none;
}

.reveal-line {
  grid-area: 1 / 1;
  opacity: 0;
  will-change: opacity, transform;
  max-width: 22ch;
}
/* drop-shadow, not text-shadow: these headlines use background-clip:text, and a
   text-shadow paints through the transparent fill instead of behind it. */
.reveal-line h1,
.reveal-line .line-xl {
  filter: drop-shadow(0 2px 18px rgba(8, 8, 10, 0.98)) drop-shadow(0 0 44px rgba(8, 8, 10, 0.85));
}
.reveal-line .sub { text-shadow: 0 1px 24px rgba(8, 8, 10, 0.95); }
.reveal-line.wide { max-width: 34ch; }
.reveal-line .sub {
  display: block;
  margin-top: 1.35rem;
  font-size: clamp(0.98rem, 1.3vw, 1.12rem);
  color: var(--muted);
  font-weight: 400;
  letter-spacing: 0;
  line-height: 1.6;
  max-width: 46ch;
  margin-left: auto;
  margin-right: auto;
}
.reveal-line .btn-group { justify-content: center; margin-top: 1.9rem; pointer-events: auto; }

/* ---------- split hero: copy left, WebGL mark right ----------
   The mark is offset in 3D rather than by cropping the canvas, so the dust and
   ambient light still cover the full bleed. Declared after the .reveal-line
   rules above so the centred defaults are overridden by source order. */
.hero-overlay {
  place-items: center start;
  text-align: left;
  padding: 0;
}
.hero-overlay > .reveal-line {
  width: 100%;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 28px;
}
/* only the display type gets a measure — a blanket max-width on every child
   wraps the kicker and stacks the buttons */
.hero-overlay h1,
.hero-overlay .line-xl { max-width: 15ch; }
.hero-overlay .sub {
  margin-left: 0;
  margin-right: 0;
  max-width: 36ch;
}
.hero-overlay .btn-group { justify-content: flex-start; }

.hero-intro .kicker { margin-bottom: 1.5rem; white-space: nowrap; }
/* scaled around the asset, not set at display max: this headline shares the
   viewport with the 3D mark */
.hero-intro h1 {
  font-size: clamp(2.4rem, 4.6vw, 4.1rem);
  letter-spacing: -0.03em;
  line-height: 1.04;
}
.hero-intro .sub { margin-top: 1.5rem; }
.hero-intro .btn-group { margin-top: 2.1rem; }

/* names the product as the payoff of the "adapts" beat, sized between the
   display line and the body sub so it reads as a second beat, not a caption */
.hero-meet {
  margin-top: 1.4rem;
  font-size: clamp(1.3rem, 2.2vw, 1.9rem);
  font-weight: 500;
  letter-spacing: -0.015em;
  pointer-events: auto;
}
.hero-meet a {
  color: var(--ink);
  border-bottom: 1px solid var(--line-2);
  padding-bottom: 3px;
  transition: border-color 0.32s var(--ease);
}
.hero-meet a:hover { border-bottom-color: var(--ink); }

/* ---------- layout family 2: low-left title card (engine) ----------
   Distinct from the hero's centre-left split so the two cinematic sections
   do not read as the same composition twice. */
.overlay-lowleft {
  place-items: end start;
  text-align: left;
  padding: 0 0 clamp(4rem, 12vh, 8rem);
}
.overlay-lowleft > .reveal-line {
  width: 100%;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 28px;
}
.overlay-lowleft .line-xl { max-width: 13ch; font-size: clamp(2.6rem, 5.6vw, 5rem); }
.overlay-lowleft .sub { margin: 1.3rem 0 0; max-width: 42ch; }

/* ---------- layout family 3: top-centre (ecosystem) ----------
   The three clusters resolve in the lower two thirds, so the copy sits above
   them rather than on top of them. */
.overlay-top {
  place-items: start center;
  text-align: center;
  padding: calc(var(--nav-h) + clamp(2.5rem, 8vh, 5.5rem)) 28px 0;
}
.overlay-top .line-xl { font-size: clamp(2.4rem, 5vw, 4.4rem); }
.overlay-top .sub { margin-top: 1.2rem; max-width: 46ch; }

.vignette {
  position: absolute;
  inset: 0;
  pointer-events: none;
  background:
    /* Scrim behind the overlay copy. Tuned against the real footage — the
       headlines carry their own drop-shadow, so this only needs to take the
       edge off, not black the frame out. */
    radial-gradient(ellipse 46% 32% at 50% 50%, rgba(8, 8, 10, 0.52), transparent 76%),
    radial-gradient(ellipse at 50% 50%, transparent 40%, rgba(8, 8, 10, 0.44) 100%),
    linear-gradient(180deg, rgba(8, 8, 10, 0.62) 0%, transparent 26%, transparent 74%, rgba(8, 8, 10, 0.84) 100%);
}

/* each cinematic section weights its scrim toward wherever its copy is anchored */
#engine-scrub .vignette {
  background:
    linear-gradient(15deg, rgba(8, 8, 10, 0.9) 0%, rgba(8, 8, 10, 0.5) 34%, transparent 58%),
    radial-gradient(ellipse at 62% 40%, transparent 30%, rgba(8, 8, 10, 0.5) 100%),
    linear-gradient(180deg, rgba(8, 8, 10, 0.5) 0%, transparent 22%, transparent 58%, rgba(8, 8, 10, 0.88) 100%);
}
#ecosystem-scrub .vignette {
  background:
    linear-gradient(180deg, rgba(8, 8, 10, 0.88) 0%, rgba(8, 8, 10, 0.6) 26%, transparent 52%),
    radial-gradient(ellipse at 50% 62%, transparent 34%, rgba(8, 8, 10, 0.46) 100%);
}

/* the hero's copy sits left, so weight its scrim left instead of centre */
#hero .vignette {
  background:
    linear-gradient(90deg, rgba(8, 8, 10, 0.86) 0%, rgba(8, 8, 10, 0.55) 38%, transparent 62%),
    radial-gradient(ellipse at 50% 50%, transparent 44%, rgba(8, 8, 10, 0.42) 100%),
    linear-gradient(180deg, rgba(8, 8, 10, 0.6) 0%, transparent 24%, transparent 78%, rgba(8, 8, 10, 0.82) 100%);
}


/* ============================================================
   Reveals
   ============================================================ */
.reveal {
  opacity: 0;
  transform: translate3d(0, 26px, 0);
  transition: opacity 0.95s var(--ease), transform 0.95s var(--ease);
}
.reveal.in { opacity: 1; transform: none; }
.reveal[data-delay="1"] { transition-delay: 0.09s; }
.reveal[data-delay="2"] { transition-delay: 0.18s; }
.reveal[data-delay="3"] { transition-delay: 0.27s; }
.reveal[data-delay="4"] { transition-delay: 0.36s; }

/* ============================================================
   Thesis
   ============================================================ */
.thesis { border-top: 1px solid var(--line); }
.thesis-quote {
  font-size: clamp(1.9rem, 4vw, 3.2rem);
  font-weight: 500;
  letter-spacing: -0.03em;
  line-height: 1.14;
  max-width: 19ch;
}
.thesis-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: clamp(2.4rem, 6vw, 5rem);
  align-items: start;
}
.thesis-body p + p { margin-top: 1.15rem; }
.thesis-body p { color: var(--muted); }

.pillars { margin-top: clamp(3.6rem, 8vh, 5.4rem); display: grid; grid-template-columns: repeat(3, 1fr); gap: 1px; background: var(--line); border: 1px solid var(--line); border-radius: var(--r); overflow: hidden; }
.pillar { background: var(--graphite); padding: 2.2rem 1.9rem; transition: background 0.4s var(--ease); }
.pillar:hover { background: var(--graphite-2); }
.pillar-n { color: var(--faint); }
.pillar h3 { margin: 1.1rem 0 0.7rem; }
.pillar p { color: var(--muted); font-size: 0.95rem; }

/* ============================================================
   Engine / stack
   ============================================================ */
.stack { display: grid; gap: 1px; background: var(--line); border: 1px solid var(--line); border-radius: var(--r); overflow: hidden; margin-top: 3.4rem; }
.stack-row {
  background: var(--graphite);
  padding: 2rem 2.1rem;
  display: grid;
  grid-template-columns: 60px 1fr 1.15fr;
  gap: 1.9rem;
  align-items: center;
  transition: background 0.4s var(--ease);
}
.stack-row:hover { background: var(--graphite-2); }
.stack-idx { color: var(--faint); }
.stack-row h3 { margin-bottom: 0.35rem; }
.stack-row .tag { color: var(--matter); }
.stack-row p { color: var(--muted); font-size: 0.96rem; margin: 0; }

/* ============================================================
   Stats
   ============================================================ */
.stat-band { margin-top: 3.2rem; }
.stat-band + .stat-band { margin-top: 2.6rem; }
.stat-label {
  display: flex;
  align-items: center;
  gap: 14px;
  color: var(--faint);
  margin-bottom: 1.5rem;
}
.stat-label::after { content: ""; flex: 1; height: 1px; background: var(--line); }

.stat-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 1px; background: var(--line); border: 1px solid var(--line); border-radius: var(--r); overflow: hidden; }
.stat {
  background: var(--graphite);
  padding: 2.1rem 1.7rem;
  transition: background 0.4s var(--ease);
}
.stat:hover { background: var(--graphite-2); }
.stat-num {
  font-size: clamp(2.1rem, 3.6vw, 3rem);
  font-weight: 600;
  letter-spacing: -0.035em;
  line-height: 1;
  background: var(--signal);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  font-variant-numeric: tabular-nums;
}
.stat-cap { color: var(--ink); font-size: 0.95rem; margin-top: 0.85rem; font-weight: 500; }
.stat-sub { color: var(--faint); font-size: 0.82rem; margin-top: 0.3rem; line-height: 1.5; }

.verified-note {
  margin-top: 1.5rem;
  color: var(--faint);
  font-size: 0.82rem;
  max-width: 76ch;
  line-height: 1.65;
}

/* ============================================================
   Products
   ============================================================ */
.products { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.4rem; margin-top: 3.4rem; }
.product {
  --accent: var(--matter);
  --accent-2: var(--matter);
  position: relative;
  background: var(--graphite);
  border: 1px solid var(--line);
  border-radius: var(--r);
  padding: 2.1rem 1.9rem 1.9rem;
  display: flex;
  flex-direction: column;
  transition: transform 0.5s var(--ease), border-color 0.5s var(--ease), background 0.5s var(--ease);
  transform-style: preserve-3d;
  overflow: hidden;
}
.product::before {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(420px circle at var(--mx, 50%) var(--my, 0%),
              color-mix(in srgb, var(--accent) 13%, transparent), transparent 62%);
  opacity: 0;
  transition: opacity 0.5s var(--ease);
  pointer-events: none;
}
.product:hover { border-color: var(--line-2); background: var(--graphite-2); }
.product:hover::before { opacity: 1; }
.product-top { display: flex; align-items: center; justify-content: space-between; gap: 14px; margin-bottom: 1.5rem; }
.product-dot {
  width: 9px; height: 9px; border-radius: 999px;
  background: var(--accent);
  box-shadow: 0 0 0 4px color-mix(in srgb, var(--accent) 16%, transparent);
  flex: none;
}
.product-badge {
  font-family: "JetBrains Mono", monospace;
  font-size: 0.61rem;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  padding: 0.32rem 0.66rem;
  border-radius: 999px;
  border: 1px solid var(--line-2);
  color: var(--muted);
}
.product-badge.live { color: var(--accent); border-color: color-mix(in srgb, var(--accent) 42%, transparent); }
.product h3 { margin-bottom: 0.55rem; }
.product .exam { color: var(--accent); font-family: "JetBrains Mono", monospace; font-size: 0.7rem; letter-spacing: 0.17em; text-transform: uppercase; }
.product p { color: var(--muted); font-size: 0.95rem; margin-top: 0.75rem; }
.product ul { list-style: none; margin: 1.35rem 0 0; display: grid; gap: 0.6rem; }
.product li { color: var(--muted); font-size: 0.89rem; display: flex; gap: 0.65rem; align-items: flex-start; }
.product li::before { content: ""; width: 4px; height: 4px; border-radius: 999px; background: var(--accent); margin-top: 0.55rem; flex: none; }
.product-links { margin-top: auto; padding-top: 1.7rem; display: flex; flex-wrap: wrap; gap: 9px; }
.plink {
  display: inline-flex; align-items: center; gap: 7px;
  font-size: 0.8rem; color: var(--muted);
  border: 1px solid var(--line-2); border-radius: 999px;
  padding: 0.46rem 0.9rem;
  transition: color 0.3s var(--ease), border-color 0.3s var(--ease), transform 0.3s var(--ease);
}
.plink:hover { color: var(--ink); border-color: var(--ink); transform: translateY(-2px); }
.plink[aria-disabled="true"] { opacity: 0.45; pointer-events: none; }
.plink svg { width: 13px; height: 13px; flex: none; }

/* ============================================================
   Impact
   ============================================================ */
.impact { border-top: 1px solid var(--line); }
.impact-quote {
  font-size: clamp(1.5rem, 3.1vw, 2.4rem);
  font-weight: 400;
  letter-spacing: -0.024em;
  line-height: 1.3;
  max-width: 26ch;
  color: var(--ink);
}
.impact-quote em { font-style: normal; color: var(--matter); }
.impact-grid { display: grid; grid-template-columns: 1.05fr 1fr; gap: clamp(2.4rem, 6vw, 5rem); align-items: center; }
.impact-list { list-style: none; display: grid; gap: 1.5rem; }
.impact-list li { display: grid; grid-template-columns: 46px 1fr; gap: 1.2rem; align-items: start; }
.impact-list .n { color: var(--faint); padding-top: 0.28rem; }
.impact-list strong { display: block; font-weight: 500; margin-bottom: 0.28rem; }
.impact-list span { color: var(--muted); font-size: 0.94rem; }

/* ============================================================
   Labs — asymmetric split, not a third card grid
   ============================================================ */
.labs-split {
  display: grid;
  grid-template-columns: 0.85fr 1.15fr;
  gap: clamp(2.6rem, 7vw, 6rem);
  align-items: start;
}
.labs-head { position: sticky; top: calc(var(--nav-h) + 3rem); }
.labs-head h2 { margin-top: 1.1rem; font-size: clamp(1.9rem, 3.6vw, 3.1rem); }
.labs-head .lead { margin-top: 1.4rem; }
.labs-list { display: grid; }
.lab-row { padding: 2.2rem 0; border-top: 1px solid var(--line); }
.lab-row:first-child { border-top: 0; padding-top: 0; }
.lab-row .mono { color: var(--faint); }
.lab-row h3 { margin: 0.9rem 0 0.6rem; }
.lab-row p { color: var(--muted); font-size: 0.96rem; max-width: 52ch; }

/* ============================================================
   FAQ — question-phrased headings with self-contained answers,
   the shape featured snippets and AI Overviews extract from
   ============================================================ */
.faq-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: clamp(2rem, 4vw, 3.4rem) clamp(2.4rem, 6vw, 5rem);
  margin-top: 3.4rem;
}
.faq-item h3 { margin-bottom: 0.8rem; }
.faq-item p { color: var(--muted); font-size: 0.96rem; max-width: 54ch; }

/* ============================================================
   CTA + footer
   ============================================================ */
.cta {
  border-top: 1px solid var(--line);
  text-align: center;
  position: relative;
  overflow: hidden;
}
.cta::before {
  content: "";
  position: absolute;
  top: 0; left: 50%;
  width: min(760px, 90%);
  height: 1px;
  transform: translateX(-50%);
  background: var(--edge);
}
.cta h2 { margin: 1.2rem auto 1.4rem; max-width: 17ch; }
.cta .lead { margin: 0 auto; }
.cta .btn-group { justify-content: center; margin-top: 2.2rem; }

.footer { border-top: 1px solid var(--line); padding: 3.4rem 0 2.6rem; }
.footer-top { display: flex; justify-content: space-between; gap: 2.4rem; flex-wrap: wrap; }
.footer-cols { display: flex; gap: clamp(2.4rem, 6vw, 5rem); flex-wrap: wrap; }
.footer-col h4 { font-size: 0.72rem; letter-spacing: 0.19em; text-transform: uppercase; color: var(--faint); font-weight: 500; font-family: "JetBrains Mono", monospace; margin-bottom: 1rem; }
.footer-col a { display: block; color: var(--muted); font-size: 0.89rem; padding: 0.26rem 0; transition: color 0.3s var(--ease); }
.footer-col a:hover { color: var(--ink); }
.footer-blurb { color: var(--faint); font-size: 0.88rem; max-width: 34ch; margin-top: 1rem; }
.footer-bottom {
  margin-top: 3rem;
  padding-top: 1.7rem;
  border-top: 1px solid var(--line);
  display: flex;
  justify-content: space-between;
  gap: 1.2rem;
  flex-wrap: wrap;
  color: var(--faint);
  font-size: 0.82rem;
}

/* ============================================================
   Responsive
   ============================================================ */
@media (max-width: 980px) {
  .thesis-grid, .impact-grid { grid-template-columns: 1fr; }
  .pillars, .products { grid-template-columns: 1fr; }
  .labs-split, .faq-grid { grid-template-columns: 1fr; }
  .labs-head { position: static; }
  .stat-grid { grid-template-columns: repeat(2, 1fr); }
  .stack-row { grid-template-columns: 40px 1fr; gap: 1rem 1.2rem; }
  .stack-row p { grid-column: 2; }
}

@media (max-width: 760px) {
  body { font-size: 16px; }
  .container { padding: 0 20px; }
  .nav-inner { padding: 0 20px; }
  .nav-burger { display: inline-flex; }

  .nav-links {
    position: fixed;
    inset: var(--nav-h) 0 0;
    background: rgba(8, 8, 10, 0.97);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    flex-direction: column;
    justify-content: center;
    gap: 1.9rem;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.42s var(--ease), visibility 0.42s;
  }
  body.menu-open .nav-links { opacity: 1; visibility: visible; }
  .nav-links a { font-size: 1.5rem; color: var(--ink); }
  .nav-cta { display: none; }

  #hero { height: 480vh; }
  #engine-scrub { height: 400vh; }
  #ecosystem-scrub { height: 380vh; }

  /* narrow viewports have no room for a side-by-side split: centre the copy
     and let the mark sit behind it (hero3d re-centres the object to match) */
  .hero-overlay { place-items: center; text-align: center; }
  .hero-overlay > .reveal-line { padding: 0 20px; }
  .hero-overlay .reveal-line > * { max-width: 100%; margin-left: auto; margin-right: auto; }
  .hero-overlay .sub { max-width: 40ch; margin-left: auto; margin-right: auto; }
  .hero-overlay .btn-group { justify-content: center; }
  .hero-intro h1 { max-width: 100%; }

  /* both cinematic families re-centre on narrow viewports; the scenes
     re-centre to match (see lattice3d.js `wide`, ecosystem3d camera pullback) */
  .overlay-lowleft { place-items: center; text-align: center; padding: 0 20px; }
  .overlay-lowleft > .reveal-line { padding: 0; }
  .overlay-lowleft .line-xl { max-width: 100%; }
  .overlay-lowleft .sub { margin-left: auto; margin-right: auto; }
  .overlay-top { padding-top: calc(var(--nav-h) + 2rem); }
  #engine-scrub .vignette,
  #ecosystem-scrub .vignette {
    background:
      radial-gradient(ellipse 62% 42% at 50% 46%, rgba(8, 8, 10, 0.74), transparent 78%),
      linear-gradient(180deg, rgba(8, 8, 10, 0.7) 0%, transparent 26%, transparent 74%, rgba(8, 8, 10, 0.86) 100%);
  }
  #hero .vignette {
    background:
      radial-gradient(ellipse 60% 40% at 50% 50%, rgba(8, 8, 10, 0.72), transparent 78%),
      linear-gradient(180deg, rgba(8, 8, 10, 0.68) 0%, transparent 26%, transparent 74%, rgba(8, 8, 10, 0.86) 100%);
  }


  .stat-grid { grid-template-columns: 1fr; }
  .impact-list li { grid-template-columns: 34px 1fr; gap: 0.9rem; }
  .footer-top { flex-direction: column; }
}

@media (prefers-reduced-motion: reduce) {
  * { animation-duration: 0.001ms !important; animation-iteration-count: 1 !important; transition-duration: 0.001ms !important; }
  .reveal { opacity: 1; transform: none; }
  /* .reveal-line opacity stays JS-driven: it tracks scroll position directly
     rather than animating on its own, and forcing it visible here would stack
     every overlay line on top of the others. */
}