/* NXS — site styles. Follows NXS Brand Guide v1.0:
   Ink #0A0A0A, Paper #FAFAFA, Signal Green #00D26A (≈5%, never text on light), Inter only. */
:root {
  --ink: #0A0A0A;
  --paper: #FAFAFA;
  --green: #00D26A;
  --grey-500: #71717A;
  --grey-400: #A1A1AA;
  --grey-200: #E4E4E7;

  --bg: var(--paper);
  --fg: var(--ink);
  --muted: var(--grey-500);
  --line: var(--grey-200);
  --panel: #F1F1F3;
  --link-line: var(--green);

  --maxw: 1160px;
  --radius: 14px;
  --font: "Inter", -apple-system, "Helvetica Neue", Arial, sans-serif;
  --mono: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: var(--ink);
    --fg: var(--paper);
    --muted: var(--grey-400);
    --line: #27272A;
    --panel: #161618;
    color-scheme: dark;
  }
}

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body {
  margin: 0; background: var(--bg); color: var(--fg);
  font: 400 17px/1.6 var(--font); font-optical-sizing: auto;
  -webkit-font-smoothing: antialiased;
}
img, svg { display: block; max-width: 100%; }
a { color: inherit; text-decoration: underline; text-decoration-color: var(--link-line); text-decoration-thickness: 2px; text-underline-offset: 4px; }
a:hover { text-decoration-thickness: 3px; }
:focus-visible { outline: 2px solid var(--green); outline-offset: 3px; border-radius: 4px; }
::selection { background: var(--green); color: var(--ink); }

.wrap { width: 100%; max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }
@media (max-width: 600px) { .wrap { padding: 0 16px; } }
.skip { position: absolute; left: -999px; top: 8px; background: var(--paper); color: var(--ink); padding: 8px 12px; z-index: 20; }
.skip:focus { left: 8px; }

h1, h2, h3 { margin: 0; line-height: 1.08; font-weight: 700; letter-spacing: -0.02em; }
h1 { font-size: clamp(40px, 6.4vw, 72px); }
h2 { font-size: clamp(30px, 4vw, 44px); }
h3 { font-size: 20px; font-weight: 600; letter-spacing: -0.01em; line-height: 1.25; }
.label { display: inline-flex; align-items: center; gap: 8px; font-size: 12px; font-weight: 600; letter-spacing: 0.12em; text-transform: uppercase; color: var(--muted); }
.label::before { content: ""; width: 8px; height: 8px; border-radius: 50%; background: var(--green); }

/* Ink zone: header + hero + any .ink section. Always dark, whatever the theme. */
.ink-zone { background: var(--ink); color: var(--paper); --muted: var(--grey-400); --line: #27272A; --panel: #161618; }

.site-header { position: sticky; top: 0; z-index: 10; border-bottom: 1px solid #1d1d20; }
.site-header .wrap { display: flex; align-items: center; justify-content: space-between; height: 72px; }
.brand { display: block; text-decoration: none; }
.brand img { width: 120px; height: auto; }
.nav { display: flex; align-items: center; gap: 28px; }
.nav a { color: var(--grey-400); text-decoration: none; font-size: 15px; font-weight: 500; }
.nav a:hover { color: var(--paper); }
.nav .cta { color: var(--ink); background: var(--green); padding: 8px 16px; border-radius: 999px; font-weight: 600; }
.nav .cta:hover { color: var(--ink); }
.nav a { white-space: nowrap; }
@media (max-width: 720px) { .nav { gap: 16px; } .nav .hide-sm { display: none; } }
@media (max-width: 480px) { .nav a:not(.cta) { display: none; } }

/* Hero */
.hero { padding: 80px 0 96px; position: relative; overflow: hidden; }
.hero .wrap { display: grid; grid-template-columns: 1.05fr 0.95fr; gap: 56px; align-items: center; }
@media (max-width: 920px) { .hero { padding: 48px 0 64px; } .hero .wrap { grid-template-columns: 1fr; gap: 40px; } }
.hero h1 .sig { color: var(--green); }
.hero .lede { font-size: clamp(17px, 2vw, 20px); color: var(--grey-400); max-width: 34em; margin: 24px 0 32px; }
.hero .lede strong { color: var(--paper); font-weight: 600; }
.actions { display: flex; flex-wrap: wrap; gap: 12px; }
.btn { display: inline-flex; align-items: center; gap: 8px; padding: 13px 22px; border-radius: 999px; font-weight: 600; font-size: 15px; text-decoration: none; border: 1px solid transparent; transition: transform .15s ease; }
.btn:hover { transform: translateY(-1px); }
.btn-green { background: var(--green); color: var(--ink); }
.btn-line { border-color: #3f3f46; color: var(--paper); }
.btn-ink { background: var(--fg); color: var(--bg); }

/* Neuron point cloud (assets/neuron.js) */
.neuron { position: relative; aspect-ratio: 1 / 1; width: 100%; max-width: 560px; justify-self: center; }
.neuron canvas { position: absolute; inset: 0; width: 100%; height: 100%; }
@media (max-width: 920px) { .neuron { max-width: 420px; margin: -8px auto 0; } }

/* Proof numbers */
.proof { border-top: 1px solid #1d1d20; }
.proof .wrap { display: grid; grid-template-columns: repeat(4, 1fr); }
.proof .stat { padding: 28px 24px 32px 0; }
.proof .stat + .stat { padding-left: 24px; border-left: 1px solid #1d1d20; }
.proof .num { font-size: clamp(30px, 3.6vw, 44px); font-weight: 700; letter-spacing: -0.02em; line-height: 1; }
.proof .num i { font-style: normal; color: var(--green); }
.proof .cap { color: var(--grey-400); font-size: 14px; margin-top: 8px; line-height: 1.45; }
@media (max-width: 820px) {
  .proof .wrap { grid-template-columns: 1fr 1fr; }
  .proof .stat:nth-child(3) { padding-left: 0; border-left: 0; }
  .proof .stat:nth-child(n+3) { border-top: 1px solid #1d1d20; }
}

/* Sections */
section.block { padding: 96px 0; border-top: 1px solid var(--line); }
@media (max-width: 600px) { section.block { padding: 64px 0; } }
.head { max-width: 680px; margin-bottom: 48px; }
.head h2 { margin-top: 14px; }
.head p { color: var(--muted); font-size: 18px; margin: 16px 0 0; }

.areas { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1px; background: var(--line); border: 1px solid var(--line); border-radius: 18px; overflow: hidden; }
@media (max-width: 900px) { .areas { grid-template-columns: 1fr 1fr; } }
@media (max-width: 600px) { .areas { grid-template-columns: 1fr; } }
.area { background: var(--bg); padding: 28px; min-height: 230px; display: flex; flex-direction: column; }
.area .ico { width: 40px; height: 40px; border-radius: 10px; background: var(--ink); display: grid; place-items: center; margin-bottom: 22px; }
@media (prefers-color-scheme: dark) { .area .ico { background: #1c1c1f; } }
.area .ico svg { width: 22px; height: 22px; stroke: var(--paper); fill: none; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }
.area .ico svg .g { stroke: var(--green); }
.area p { color: var(--muted); margin: 10px 0 0; font-size: 16px; }
.area .kw { margin-top: auto; padding-top: 18px; font: 500 12px/1.5 var(--mono); color: var(--muted); }

.principles { display: grid; grid-template-columns: repeat(2, 1fr); gap: 20px 56px; }
@media (max-width: 760px) { .principles { grid-template-columns: 1fr; } }
.principle { display: grid; grid-template-columns: 44px 1fr; gap: 4px 16px; padding: 24px 0; border-top: 1px solid var(--line); }
.principle .n { font: 600 13px var(--mono); color: var(--muted); padding-top: 4px; }
.principle:last-child:nth-child(odd) { grid-column: 1 / -1; }
.principle p { max-width: 62ch; grid-column: 2; color: var(--muted); margin: 6px 0 0; }

/* Why NXS (Ink band) */
.why { padding: 104px 0; }
@media (max-width: 600px) { .why { padding: 68px 0; } }
.why .head { max-width: 820px; }
.why h2 .sig { color: var(--green); }
.pillars { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1px; background: #27272A; border: 1px solid #27272A; border-radius: 18px; overflow: hidden; }
@media (max-width: 860px) { .pillars { grid-template-columns: 1fr; } }
.pillar { background: var(--ink); padding: 32px 28px 36px; }
.pillar .n { display: inline-block; font: 600 13px var(--mono); color: var(--green); margin-bottom: 18px; }
.pillar p { color: var(--grey-400); margin: 12px 0 0; font-size: 16px; }
.thesis { font-size: clamp(20px, 2.4vw, 26px); line-height: 1.4; letter-spacing: -0.01em; color: var(--grey-400); margin: 48px 0 0; max-width: 34em; }
.thesis strong { color: var(--paper); font-weight: 600; }

/* Timeline */
.timeline { list-style: none; margin: 0; padding: 0; position: relative; }
.timeline::before { content: ""; position: absolute; left: 132px; top: 8px; bottom: 8px; width: 1px; background: var(--line); }
.timeline li { display: grid; grid-template-columns: 112px 1fr; gap: 41px; padding: 0 0 36px; position: relative; }
.timeline li::after { content: ""; position: absolute; left: 128px; top: 8px; width: 9px; height: 9px; border-radius: 50%; background: var(--bg); border: 2px solid var(--fg); }
.timeline li.now::after { background: var(--green); border-color: var(--green); }
.timeline .yr { font: 600 15px/1.6 var(--mono); text-align: right; }
.timeline p { color: var(--muted); margin: 6px 0 0; max-width: 60ch; }
@media (max-width: 600px) {
  .timeline::before { left: 4px; }
  .timeline li { grid-template-columns: 1fr; gap: 2px; padding-left: 28px; }
  .timeline li::after { left: 0; }
  .timeline .yr { text-align: left; }
}

.founder { display: grid; grid-template-columns: 0.85fr 1.15fr; gap: 64px; align-items: start; }
@media (max-width: 880px) { .founder { grid-template-columns: 1fr; gap: 32px; } }
.card { background: var(--panel); border-radius: 18px; padding: 28px; }
.card .name { font-size: 20px; font-weight: 700; letter-spacing: -0.01em; }
.card .creds { display: flex; flex-wrap: wrap; gap: 8px; margin: 14px 0 18px; }
.chip { font-size: 13px; font-weight: 600; border: 1px solid var(--line); background: var(--bg); border-radius: 999px; padding: 4px 12px; }
.card p { color: var(--muted); margin: 0; font-size: 15px; }
.founder .story p { font-size: 18px; color: var(--muted); margin: 0 0 18px; }
.founder .story p strong { color: var(--fg); font-weight: 600; }

.stack { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 8px; }
.stack span { font: 500 13px var(--mono); border: 1px solid var(--line); border-radius: 8px; padding: 6px 10px; color: var(--muted); }

/* Closing CTA (Ink) */
.closing { padding: 96px 0; }
.closing .wrap { display: grid; grid-template-columns: 1.2fr 0.8fr; gap: 40px; align-items: end; }
@media (max-width: 820px) { .closing .wrap { grid-template-columns: 1fr; } }
.closing h2 .sig { color: var(--green); }
.closing p { color: var(--grey-400); font-size: 18px; margin: 18px 0 0; max-width: 40ch; }
.closing .actions { justify-content: flex-end; }
@media (max-width: 820px) { .closing .actions { justify-content: flex-start; } }

/* Footer */
.site-footer { padding: 40px 0 56px; border-top: 1px solid #1d1d20; font-size: 14px; color: var(--grey-400); }
.site-footer .wrap { display: flex; flex-wrap: wrap; justify-content: space-between; align-items: flex-start; gap: 28px; }
.site-footer img { width: 120px; margin-bottom: 12px; }
.site-footer nav { display: flex; flex-wrap: wrap; gap: 10px 24px; }
.site-footer a { color: var(--grey-400); text-decoration: none; }
.site-footer a:hover { color: var(--paper); }

/* Long-form (policy) pages */
.doc { padding: 64px 0 96px; }
.doc .wrap { max-width: 760px; }
.doc .crumbs { font-size: 14px; color: var(--muted); margin-bottom: 20px; }
.doc h1 { font-size: clamp(34px, 5vw, 48px); }
.doc .meta { color: var(--muted); font-size: 16px; margin: 14px 0 36px; }
.doc h2 { font-size: 20px; font-weight: 600; letter-spacing: -0.01em; margin: 40px 0 10px; }
.doc p, .doc li { color: var(--muted); }
.doc ul { padding-left: 1.2em; }
.doc li { margin: 6px 0; }
.doc .callout { background: var(--panel); border-left: 3px solid var(--green); border-radius: 0 12px 12px 0; padding: 18px 22px; color: var(--fg); margin: 0 0 8px; }
.notice { background: var(--panel); border-radius: 12px; padding: 14px 18px; font-size: 15px; color: var(--muted); margin: 0 0 28px; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .btn { transition: none; }
  .lab .halo { animation: none; }
}