:root {
  --ink: #1a2430;
  --mute: #5b6774;
  --paper: #f6f3ea;
  --paper-2: #fffdf6;
  --navy: #1e3a5f;
  --teal: #3a7d78;
  --amber: #c48a2a;
  --line: rgba(30, 58, 95, 0.16);
  --serif: "Noto Serif SC", "Songti SC", serif;
  --sans: "Noto Sans SC", "PingFang SC", sans-serif;
  --mono: "IBM Plex Mono", ui-monospace, monospace;
}
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
section[id] { scroll-margin-top: 86px; }
body { margin: 0; color: var(--ink); background: var(--paper); font-family: var(--sans); font-size: 16px; line-height: 1.72; }
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
.app-link, .live { color: var(--navy); border-bottom: 1px solid rgba(30,58,95,.35); }
footer .app-link { color: #c9d4e4; }
button { font-family: inherit; cursor: pointer; }
code { font-family: var(--mono); background: rgba(58,125,120,.12); padding: 0.05em 0.35em; }
.fiber { pointer-events: none; position: fixed; inset: 0; z-index: 50; opacity: 0.12; background-image: url("images/texture.webp"); background-size: 440px auto; mix-blend-mode: multiply; }
.skip { position: absolute; left: -999px; }
.skip:focus { left: 12px; top: 12px; z-index: 80; background: #fff; padding: 8px; }

.nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 40;
  display: flex; align-items: center; justify-content: space-between; gap: 12px;
  padding: 10px 20px; background: rgba(246,243,234,.94); border-bottom: 1px solid var(--line);
}
.brand { display: flex; align-items: center; gap: 10px; font-family: var(--serif); font-weight: 700; }
.brand small { display: block; font-family: var(--mono); font-size: 10px; color: var(--mute); letter-spacing: 0.12em; font-weight: 400; }
.arena { width: 26px; height: 26px; border: 3px solid var(--navy); border-radius: 50%; box-shadow: inset 0 0 0 5px var(--paper), 0 0 0 2px var(--teal); }
.nav-toggle { display: none; background: transparent; border: 1px solid var(--navy); padding: 6px 12px; }
.nav-links { display: flex; gap: 14px; align-items: center; font-size: 13px; }
.nav-links a { color: var(--mute); }
.nav-links a.is-active, .nav-links a:hover { color: var(--navy); }
.nav-links .live { padding: 5px 10px; border: 1px solid var(--navy); }

.hero { position: relative; min-height: 100vh; display: grid; align-items: end; overflow: hidden; color: var(--paper-2); }
.hero picture { position: absolute; inset: 0; }
.hero img { width: 100%; height: 100%; object-fit: cover; }
.hero::after { content: ""; position: absolute; inset: 0; background: linear-gradient(180deg, rgba(26,36,48,.2), rgba(26,36,48,.88) 78%); }
.hero-copy { position: relative; z-index: 1; padding: 18vh 7vw 10vh; max-width: 760px; }
.kicker, .vlabel { font-family: var(--mono); letter-spacing: 0.18em; font-size: 11px; color: #c9d4e4; margin: 0 0 12px; }
.vlabel { color: var(--navy); }
h1, h2, h3 { font-family: var(--serif); margin: 0 0 14px; line-height: 1.08; word-break: keep-all; }
h1 { font-size: clamp(36px, 6.2vw, 80px); }
h2 { font-size: clamp(24px, 3.2vw, 38px); }
h3 { font-size: 20px; }
.lead { max-width: 40em; word-break: keep-all; overflow-wrap: anywhere; }
.stands { display: grid; grid-template-columns: repeat(4, 1fr); gap: 8px; margin: 20px 0; max-width: 520px; }
.stands span { text-align: center; padding: 8px 4px; border: 1px solid rgba(255,253,246,.3); font-family: var(--mono); font-size: 12px; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 10px; }
.btn { display: inline-flex; align-items: center; justify-content: center; min-height: 44px; padding: 10px 16px; border: 1px solid currentColor; font-size: 14px; }
.btn-fill { background: var(--teal); color: #fff; border-color: var(--teal); }
.btn-ghost { background: transparent; color: inherit; }

.wrap { width: min(1100px, calc(100% - 40px)); margin: 0 auto; padding: 88px 0; }
.section-head { display: grid; grid-template-columns: 140px 1fr; gap: 20px; margin-bottom: 36px; }
.section-head p:last-child { color: var(--mute); margin: 0; }
.tri, .bench-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; }
.card { background: var(--paper-2); border: 1px solid var(--line); padding: 18px; min-height: 200px; border-radius: 40px 8px; }
.card.warn { outline: 1px solid var(--amber); }
.stamp { display: inline-block; font-family: var(--mono); font-size: 10px; letter-spacing: 0.14em; border: 1px solid var(--navy); color: var(--navy); padding: 2px 8px; margin-bottom: 8px; }
.card ul, .io ul, .rule-list { margin: 0; padding-left: 1.1em; }
.card li, .io li, .rule-list li { margin: 0.35em 0; }
.alt { background: #ece7da; }

.row { display: grid; grid-template-columns: 1fr 1fr; gap: 32px; align-items: center; margin-bottom: 60px; }
.row.flip { direction: rtl; }
.row.flip > * { direction: ltr; }
.num { font-family: var(--mono); color: var(--teal); display: block; margin-bottom: 6px; }
figure { margin: 0; }
figure img { width: 100%; height: 300px; object-fit: cover; border-radius: 50% 8px 50% 8px; }
figcaption { margin-top: 8px; font-size: 13px; color: var(--mute); }
.demo { margin-top: 16px; padding: 12px; border: 1px dashed var(--navy); }
.demo-kicker { margin: 0 0 8px; font-family: var(--mono); font-size: 11px; color: var(--navy); }

.io { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.io > div { background: var(--paper-2); padding: 18px; border-left: 8px solid var(--navy); }
footer { background: var(--navy); color: var(--paper); }
.footer-inner { display: flex; justify-content: space-between; gap: 12px; padding: 28px 0; font-size: 13px; }

@media (max-width: 960px) {
  .hero, .row, .section-head, .tri, .bench-grid, .io, .footer-inner, .stands { grid-template-columns: 1fr 1fr; }
  .hero, .row, .section-head, .tri, .bench-grid, .io, .footer-inner { grid-template-columns: 1fr; }
  .hero { min-height: 100svh; }
  .hero-copy { padding: 110px 20px 48px; }
  .nav-toggle { display: inline-flex; }
  .nav-links { display: none; position: absolute; top: 100%; left: 0; right: 0; flex-direction: column; padding: 12px 16px; background: var(--paper-2); }
  .nav-links.open { display: flex; }
  figure img { height: 210px; border-radius: 24px; }
}