/* Cogniartha website. Tokens checked for WCAG AA contrast on their intended backgrounds (see README). */
:root {
  --bg: #0b1020;
  --surface: #121a2b;
  --surface-2: #18223a;
  --line: #24304a;
  --text: #f8fafc;
  --text-2: #b4bfd0;
  --muted: #96a3b8;
  --primary: #6477f5;      /* accents, borders, focus */
  --primary-fill: #4f5fe0; /* button fill: white text 4.96:1 */
  --link: #8b9afb;         /* 7.3:1 on --bg */
  --teal: #45c4b0;
  --amber: #f0a35e;
  --danger: #ff8a8a;
  --radius: 14px;
  --radius-sm: 9px;
  --wrap: 1180px;
  --ease: cubic-bezier(.2, .8, .2, 1);
  color-scheme: dark;
}
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-padding-top: 5rem; }
body {
  margin: 0; background: var(--bg); color: var(--text);
  font: 100%/1.6 system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  -webkit-font-smoothing: antialiased; text-rendering: optimizeLegibility;
}
img, video { max-width: 100%; height: auto; display: block; }
figure { margin: 0; }
a { color: var(--link); text-underline-offset: .18em; }
a:hover { color: #b3bdfd; }
:focus-visible { outline: 2px solid var(--primary); outline-offset: 3px; border-radius: 4px; }
.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }
.skip { position: absolute; left: 1rem; top: -3rem; z-index: 100; background: var(--primary-fill); color: #fff; padding: .5rem .9rem; border-radius: var(--radius-sm); }
.skip:focus { top: 1rem; }
.wrap { width: min(var(--wrap), 100% - 2.5rem); margin-inline: auto; }
.muted { color: var(--muted); }
.small { font-size: .875rem; }
.num { font-variant-numeric: tabular-nums; }

/* type: tight leading and negative tracking as size grows; body near 0 */
h1, h2, h3 { line-height: 1.12; margin: 0 0 .6em; font-weight: 650; }
h1 { font-size: clamp(2.2rem, 4.4vw, 3.5rem); letter-spacing: -.028em; line-height: 1.04; }
h2 { font-size: clamp(1.7rem, 3.2vw, 2.55rem); letter-spacing: -.02em; }
h3 { font-size: 1.15rem; letter-spacing: -.005em; }
p { margin: 0 0 1em; }
.lead { font-size: clamp(1.05rem, 1.6vw, 1.25rem); color: var(--text-2); max-width: 46rem; }
.eyebrow { display: inline-block; font-size: .78rem; letter-spacing: .12em; text-transform: uppercase; color: var(--teal); font-weight: 600; margin-bottom: 1rem; }

/* header: translucent material, content scrolls beneath */
.site-header { position: sticky; top: 0; z-index: 50; background: rgba(11, 16, 32, .72); backdrop-filter: blur(16px) saturate(160%); -webkit-backdrop-filter: blur(16px) saturate(160%); border-bottom: 1px solid transparent; transition: border-color .3s, background .3s; }
.site-header.scrolled { border-bottom-color: var(--line); background: rgba(11, 16, 32, .86); }
.header-row { display: flex; align-items: center; justify-content: space-between; min-height: 4.25rem; gap: 1rem; }
.brand { display: inline-flex; align-items: center; gap: .6rem; color: var(--text); text-decoration: none; font-weight: 650; letter-spacing: -.01em; font-size: 1.08rem; }
.brand img { border-radius: 8px; }
.site-nav { display: flex; align-items: center; gap: 1.6rem; }
.site-nav a:not(.btn) { color: var(--text-2); text-decoration: none; font-size: .95rem; }
.site-nav a:not(.btn):hover, .site-nav a[aria-current="page"] { color: var(--text); }
.site-nav a[aria-current="page"]:not(.btn) { box-shadow: 0 2px 0 var(--primary); }
.nav-toggle { display: none; background: none; border: 1px solid var(--line); border-radius: var(--radius-sm); width: 2.75rem; height: 2.75rem; color: var(--text); cursor: pointer; }
.bars, .bars::before, .bars::after { display: block; width: 18px; height: 2px; background: currentColor; margin: auto; position: relative; transition: transform .25s var(--ease), opacity .2s; }
.bars::before, .bars::after { content: ""; position: absolute; left: 0; }
.bars::before { top: -6px; } .bars::after { top: 6px; }
.nav-toggle[aria-expanded="true"] .bars { background: transparent; }
.nav-toggle[aria-expanded="true"] .bars::before { transform: translateY(6px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .bars::after { transform: translateY(-6px) rotate(-45deg); }
@media (max-width: 920px) {
  .nav-toggle { display: grid; place-items: center; }
  .site-nav { position: absolute; inset: 100% 0 auto; flex-direction: column; align-items: stretch; gap: 0; padding: .5rem 1.25rem 1.25rem; background: var(--bg); border-bottom: 1px solid var(--line); transform-origin: top; }
  .js .site-nav:not(.open) { display: none; }
  .site-nav a:not(.btn) { padding: .85rem 0; border-bottom: 1px solid var(--line); font-size: 1rem; }
  .site-nav a[aria-current="page"]:not(.btn) { box-shadow: none; color: var(--teal); }
  .site-nav .btn { margin-top: 1rem; }
  .site-nav.open { animation: drop .22s var(--ease); }
}
@keyframes drop { from { opacity: 0; transform: translateY(-6px); } }

/* buttons: feedback on press, not release */
.btn { display: inline-flex; align-items: center; justify-content: center; gap: .5rem; font: inherit; font-weight: 600; font-size: 1rem; line-height: 1; padding: .95rem 1.35rem; border-radius: 999px; border: 1px solid transparent; text-decoration: none; cursor: pointer; transition: transform .1s ease-out, background .2s, border-color .2s; }
.btn:active { transform: scale(.97); }
.btn-primary { background: var(--primary-fill); color: #fff; }
.btn-primary:hover { background: #5a6ae8; color: #fff; }
.btn-ghost { border-color: var(--line); color: var(--text); background: rgba(255, 255, 255, .02); }
.btn-ghost:hover { border-color: var(--primary); color: var(--text); }
.btn-sm { padding: .62rem 1rem; font-size: .9rem; }
.btn[disabled], .btn[aria-busy="true"] { opacity: .65; cursor: progress; }
.actions { display: flex; flex-wrap: wrap; gap: .8rem; margin-top: 1.8rem; }

/* sections */
.section { padding: clamp(4rem, 9vw, 7rem) 0; }
.section + .section { border-top: 1px solid rgba(36, 48, 74, .6); }
.section-head { max-width: 48rem; margin-bottom: 2.6rem; }
.hero + .section { padding-top: clamp(.5rem, 2vw, 1.5rem); }
.band { background: linear-gradient(180deg, var(--surface) 0%, var(--bg) 100%); }

/* hero */
.hero { padding: clamp(3.5rem, 8vw, 6.5rem) 0 clamp(3rem, 6vw, 5rem); position: relative; overflow: hidden; }
.hero::before { content: ""; position: absolute; inset: -40% -10% auto; height: 80%; background: radial-gradient(50% 50% at 50% 50%, rgba(100, 119, 245, .16), transparent 70%); pointer-events: none; }
.hero-grid { display: grid; grid-template-columns: 1fr 1.2fr; gap: clamp(2rem, 4vw, 3.5rem); align-items: center; position: relative; }
@media (max-width: 980px) { .hero-grid { grid-template-columns: 1fr; } }
.frame { position: relative; border-radius: var(--radius); border: 1px solid var(--line); background: var(--surface); overflow: hidden; box-shadow: 0 30px 80px -30px rgba(0, 0, 0, .7), 0 0 0 1px rgba(255, 255, 255, .02) inset; }
.frame img { aspect-ratio: 16 / 9; object-fit: cover; width: 100%; }
figcaption, .caption { font-size: .8rem; color: var(--muted); padding: .65rem .9rem; border-top: 1px solid var(--line); background: var(--surface); }

/* cards */
.grid { display: grid; gap: 1.1rem; }
.grid-3 { grid-template-columns: repeat(auto-fit, minmax(16.5rem, 1fr)); }
.grid-2 { grid-template-columns: repeat(auto-fit, minmax(21rem, 1fr)); }
.card { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 1.5rem; transition: border-color .25s, transform .25s var(--ease); }
.card p:last-child, .card ul:last-child { margin-bottom: 0; }
a.card { display: block; color: inherit; text-decoration: none; }
a.card:hover { border-color: rgba(100, 119, 245, .65); transform: translateY(-2px); }
.card .more { color: var(--link); font-size: .92rem; font-weight: 600; }
.icon { width: 2.4rem; height: 2.4rem; border-radius: 10px; display: grid; place-items: center; background: rgba(100, 119, 245, .14); color: var(--link); margin-bottom: 1rem; }
.icon svg { width: 1.25rem; height: 1.25rem; }
ul.ticks { list-style: none; padding: 0; margin: 0 0 1rem; }
ul.ticks li { position: relative; padding-left: 1.4rem; margin: .45rem 0; color: var(--text-2); }
ul.ticks li::before { content: ""; position: absolute; left: .1rem; top: .62em; width: .5rem; height: .5rem; border-radius: 50%; background: var(--teal); }

/* status badges: what is demonstrated vs specified */
.badge { display: inline-flex; align-items: center; gap: .35rem; font-size: .72rem; font-weight: 600; letter-spacing: .04em; text-transform: uppercase; padding: .28rem .55rem; border-radius: 999px; border: 1px solid; white-space: nowrap; }
.badge-live { color: var(--teal); border-color: rgba(69, 196, 176, .45); background: rgba(69, 196, 176, .08); }
.badge-val { color: var(--amber); border-color: rgba(240, 163, 94, .45); background: rgba(240, 163, 94, .08); }
.badge-spec { color: var(--muted); border-color: var(--line); }

/* tabs */
.tablist { display: flex; flex-wrap: wrap; gap: .45rem; margin-bottom: 1.4rem; }
.tab { font: inherit; font-size: .93rem; color: var(--text-2); background: transparent; border: 1px solid var(--line); border-radius: 999px; padding: .55rem .95rem; cursor: pointer; transition: background .2s, color .2s, border-color .2s; }
.tab:hover { color: var(--text); border-color: #34446a; }
.tab[aria-selected="true"] { color: #fff; background: var(--primary-fill); border-color: var(--primary-fill); }
.tabpanel[hidden] { display: none; }
.tabpanel { animation: fade .3s var(--ease); }
@keyframes fade { from { opacity: 0; } }
.split { display: grid; grid-template-columns: 1fr 1.25fr; gap: 2rem; align-items: start; }
@media (max-width: 900px) { .split { grid-template-columns: 1fr; } }

/* workflow diagram */
.flow { display: grid; grid-template-columns: repeat(5, 1fr); gap: 1rem; position: relative; counter-reset: step; }
.flow::before { content: ""; position: absolute; left: 6%; right: 6%; top: 1.45rem; height: 2px; background: linear-gradient(90deg, var(--primary), var(--teal)); transform-origin: left; transform: scaleX(var(--p, 1)); transition: transform 1.2s var(--ease); }
.js .flow:not(.in) { --p: 0; }
.flow li { list-style: none; position: relative; text-align: center; }
.flow .dot { width: 2.9rem; height: 2.9rem; margin: 0 auto .9rem; border-radius: 50%; display: grid; place-items: center; background: var(--surface-2); border: 1px solid var(--primary); color: var(--text); font-weight: 650; position: relative; font-variant-numeric: tabular-nums; }
.flow h3 { font-size: 1rem; margin-bottom: .35rem; }
.flow p { font-size: .88rem; color: var(--muted); margin: 0; }
.flow ol, ol.flow { padding: 0; margin: 0; }
@media (max-width: 860px) {
  .flow { grid-template-columns: 1fr; gap: 1.4rem; }
  .flow::before { left: 1.45rem; right: auto; top: 1rem; bottom: 1rem; width: 2px; height: auto; transform-origin: top; transform: scaleY(var(--p, 1)); background: linear-gradient(180deg, var(--primary), var(--teal)); }
  .flow li { text-align: left; display: grid; grid-template-columns: 2.9rem 1fr; column-gap: 1rem; }
  .flow .dot { margin: 0; grid-row: span 2; }
}

/* layers diagram (architecture) */
.layers { display: grid; gap: .7rem; }
.layer { display: grid; grid-template-columns: 11rem 1fr; gap: 1rem; align-items: center; background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 1rem 1.2rem; }
.layer strong { font-size: .95rem; }
.layer .chips { display: flex; flex-wrap: wrap; gap: .45rem; }
.chip { font-size: .82rem; color: var(--text-2); background: var(--surface-2); border: 1px solid var(--line); border-radius: 8px; padding: .3rem .6rem; }
.layer.compute { border-color: rgba(69, 196, 176, .5); }
.layer.intel { border-color: rgba(100, 119, 245, .55); }
@media (max-width: 700px) { .layer { grid-template-columns: 1fr; } }

/* separation diagram */
.sep { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1rem; }
@media (max-width: 860px) { .sep { grid-template-columns: 1fr; } }
.sep .card { border-top: 3px solid var(--line); }
.sep .lang { border-top-color: var(--link); }
.sep .ml { border-top-color: var(--amber); }
.sep .det { border-top-color: var(--teal); }
.sep .tag { font-size: .78rem; color: var(--muted); text-transform: uppercase; letter-spacing: .08em; }

/* facts strip: verified product facts only */
.facts { display: grid; grid-template-columns: repeat(auto-fit, minmax(10rem, 1fr)); gap: 1rem; margin-top: 2.5rem; }
.fact { border-left: 2px solid var(--primary); padding: .2rem 0 .2rem 1rem; }
.fact b { display: block; font-size: 2rem; letter-spacing: -.02em; font-variant-numeric: tabular-nums; line-height: 1.1; }
.fact span { color: var(--muted); font-size: .9rem; }

/* tables */
.table-wrap { overflow-x: auto; border: 1px solid var(--line); border-radius: var(--radius); }
table { border-collapse: collapse; width: 100%; font-size: .93rem; }
th, td { text-align: left; padding: .8rem 1rem; border-bottom: 1px solid var(--line); vertical-align: top; }
th { color: var(--muted); font-weight: 600; font-size: .78rem; text-transform: uppercase; letter-spacing: .06em; background: var(--surface); position: sticky; top: 0; }
tr:last-child td { border-bottom: 0; }
td:first-child { color: var(--text); font-weight: 550; }
td { color: var(--text-2); }

/* video player */
.player { display: grid; grid-template-columns: minmax(0, 1fr) 20rem; gap: 1.2rem; align-items: start; }
.player.compact { grid-template-columns: 1fr; }
@media (max-width: 980px) { .player { grid-template-columns: 1fr; } }
.player-frame { position: relative; aspect-ratio: 16 / 9; background: #000; border-radius: var(--radius); overflow: hidden; border: 1px solid var(--line); }
.player-frame video, .player-frame iframe { position: absolute; inset: 0; width: 100%; height: 100%; border: 0; }
.player-now { margin-top: .75rem; color: var(--text-2); font-size: .92rem; display: flex; flex-wrap: wrap; gap: .5rem 1rem; align-items: center; justify-content: space-between; }
.chapters { list-style: none; margin: 0; padding: .4rem; max-height: 34rem; overflow-y: auto; background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); counter-reset: none; }
.chapters a { display: grid; grid-template-columns: 2rem 1fr auto; gap: .5rem; align-items: baseline; padding: .55rem .6rem; border-radius: 8px; color: var(--text-2); text-decoration: none; font-size: .9rem; }
.chapters a:hover { background: var(--surface-2); color: var(--text); }
.chapters a[aria-current="true"] { background: rgba(79, 95, 224, .22); color: #fff; }
.chapters .n, .chapters .t { color: var(--muted); font-variant-numeric: tabular-nums; font-size: .8rem; }
.player select { font: inherit; font-size: .9rem; color: var(--text); background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius-sm); padding: .5rem .7rem; max-width: 100%; }

/* forms */
.form-card { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: clamp(1.4rem, 3vw, 2.2rem); }
.fields { display: grid; grid-template-columns: 1fr 1fr; gap: 1.1rem 1.2rem; }
.fields .full { grid-column: 1 / -1; }
@media (max-width: 680px) { .fields { grid-template-columns: 1fr; } }
.field label, .field legend { display: block; font-weight: 600; font-size: .92rem; margin-bottom: .4rem; }
.req { color: var(--muted); font-weight: 400; font-size: .8rem; }
input[type="text"], input[type="email"], select, textarea {
  width: 100%; font: inherit; font-size: 1rem; color: var(--text); background: var(--bg); border: 1px solid #2c3958; border-radius: var(--radius-sm);
  padding: .75rem .85rem; transition: border-color .15s, box-shadow .15s;
}
textarea { min-height: 9rem; resize: vertical; }
input:focus, select:focus, textarea:focus { outline: none; border-color: var(--primary); box-shadow: 0 0 0 3px rgba(100, 119, 245, .25); }
[aria-invalid="true"] { border-color: var(--danger) !important; }
fieldset { border: 0; padding: 0; margin: 0; min-width: 0; }
.checks { display: grid; grid-template-columns: repeat(auto-fit, minmax(15rem, 1fr)); gap: .5rem .9rem; }
.check, .field label.check { display: flex; gap: .6rem; align-items: flex-start; font-size: .95rem; font-weight: 400; color: var(--text-2); cursor: pointer; margin: 0; }
.check input { margin-top: .25rem; width: 1.05rem; height: 1.05rem; accent-color: var(--primary-fill); flex: none; }
.hint { color: var(--muted); font-size: .82rem; margin-top: .35rem; }
.err { color: var(--danger); font-size: .85rem; margin-top: .35rem; }
.err:empty { display: none; }
.hp { position: absolute; left: -10000px; width: 1px; height: 1px; overflow: hidden; }
.form-status { margin-top: 1rem; padding: .85rem 1rem; border-radius: var(--radius-sm); border: 1px solid rgba(255, 138, 138, .4); background: rgba(255, 138, 138, .07); color: #ffc2c2; }
.form-status:empty { display: none; }
.success { text-align: left; padding: 2rem; border: 1px solid rgba(69, 196, 176, .45); background: rgba(69, 196, 176, .07); border-radius: var(--radius); }
.success h2 { font-size: 1.5rem; }
.counter { float: right; font-weight: 400; color: var(--muted); font-size: .8rem; font-variant-numeric: tabular-nums; }

/* prose (privacy) */
.prose { max-width: 46rem; color: var(--text-2); }
.prose h2 { font-size: 1.35rem; color: var(--text); margin-top: 2.2rem; }
.prose li { margin: .35rem 0; }
.note { border-left: 3px solid var(--amber); padding: .8rem 1rem; background: rgba(240, 163, 94, .06); border-radius: 0 var(--radius-sm) var(--radius-sm) 0; color: var(--text-2); }

/* footer */
.site-footer { border-top: 1px solid var(--line); padding: 3.5rem 0 2rem; background: #090d1a; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr; gap: 2rem; }
@media (max-width: 720px) { .footer-grid { grid-template-columns: 1fr; } }
.footer-grid nav a { display: block; color: var(--text-2); text-decoration: none; padding: .25rem 0; font-size: .93rem; }
.footer-grid nav a:hover { color: var(--text); }
.footer-h { font-size: .78rem; text-transform: uppercase; letter-spacing: .1em; color: var(--muted); margin-bottom: .8rem; font-weight: 600; }
.footer-base { margin-top: 2.5rem; padding-top: 1.5rem; border-top: 1px solid var(--line); }

/* reveal: only once JS is running, and never for reduced motion */
.js .reveal { opacity: 0; transform: translateY(14px); transition: opacity .6s var(--ease), transform .6s var(--ease); }
.js .reveal.in { opacity: 1; transform: none; }
.js .reveal.d1 { transition-delay: .07s; } .js .reveal.d2 { transition-delay: .14s; } .js .reveal.d3 { transition-delay: .21s; }

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation: none !important; transition-duration: .01ms !important; scroll-behavior: auto !important; }
  .js .reveal { opacity: 1; transform: none; }
  .js .flow:not(.in) { --p: 1; }
  a.card:hover { transform: none; }
}
@media (prefers-reduced-transparency: reduce) {
  .site-header, .site-header.scrolled { background: var(--bg); backdrop-filter: none; -webkit-backdrop-filter: none; }
}
@media (prefers-contrast: more) {
  :root { --line: #5a6a8c; --muted: #c3ccda; --text-2: #dbe2ec; }
}

/* utilities (no inline style attributes anywhere: the CSP forbids them) */
.mt { margin-top: 1.2rem; }
.items-center { align-items: center; }