:root {
  --ink: #1a1512;
  --mute: #6a5c52;
  --rice: #f6f0e4;
  --rice-2: #fffaf1;
  --navy: #1b2a4a;
  --navy-2: #0f1c33;
  --vermilion: #b42318;
  --vermilion-2: #d4533a;
  --gold: #c4a35a;
  --line: rgba(26, 21, 18, 0.14);
  --serif: "Noto Serif SC", "Songti SC", serif;
  --sans: "Noto Sans SC", "PingFang SC", sans-serif;
  --mono: "DM Mono", ui-monospace, monospace;
  --shadow: 0 16px 36px rgba(15, 28, 51, 0.16);
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
section[id] { scroll-margin-top: 108px; }
body {
  margin: 0;
  color: var(--ink);
  background: var(--rice);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.75;
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
.app-link, .live { color: var(--vermilion); border-bottom: 1px solid rgba(180, 35, 24, 0.35); }
footer .app-link { color: var(--gold); border-bottom-color: rgba(196, 163, 90, 0.45); }
button { font-family: inherit; cursor: pointer; }
code {
  font-family: var(--mono);
  font-size: 0.9em;
  background: rgba(180, 35, 24, 0.08);
  padding: 0.05em 0.35em;
}

.paper {
  pointer-events: none;
  position: fixed;
  inset: 0;
  z-index: 50;
  opacity: 0.14;
  background-image: url("images/texture.webp");
  background-size: 480px auto;
  mix-blend-mode: multiply;
}

.skip { position: absolute; left: -999px; }
.skip:focus { left: 12px; top: 12px; z-index: 80; background: var(--rice-2); padding: 8px 12px; }

.mast {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 40;
  background: var(--rice-2);
  border-bottom: 1px solid var(--line);
}
.docno {
  margin: 0;
  padding: 6px 28px 0;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--vermilion);
}
.mast-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 6px 28px 10px;
}
.red-rule {
  height: 6px;
  background: linear-gradient(90deg, var(--vermilion), var(--vermilion-2) 40%, var(--navy));
}
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: var(--serif);
  font-weight: 700;
  font-size: 20px;
}
.brand small {
  display: block;
  font-family: var(--mono);
  font-weight: 400;
  font-size: 10px;
  letter-spacing: 0.2em;
  color: var(--mute);
}
.chop {
  width: 42px;
  height: 42px;
  border: 2px solid var(--vermilion);
  color: var(--vermilion);
  display: grid;
  place-items: center;
  font-family: var(--serif);
  font-size: 22px;
  transform: rotate(-8deg);
}
.nav-toggle {
  display: none;
  background: transparent;
  border: 1px solid var(--vermilion);
  color: var(--vermilion);
  padding: 6px 12px;
}
.nav-links { display: flex; gap: 16px; align-items: center; font-size: 13px; }
.nav-links a { color: var(--mute); }
.nav-links a.is-active, .nav-links a:hover { color: var(--vermilion); }
.nav-links .live {
  padding: 5px 12px;
  border: 1px solid var(--vermilion);
}

.hero {
  position: relative;
  min-height: 100vh;
  display: grid;
  align-items: end;
  color: #fffaf1;
  overflow: hidden;
}
.hero picture { position: absolute; inset: 0; }
.hero picture img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.hero::after {
  content: "";
  position: absolute;
  inset: 0;
  background:
    linear-gradient(180deg, rgba(15, 28, 51, 0.25) 0%, rgba(15, 28, 51, 0.55) 45%, rgba(15, 28, 51, 0.92) 100%);
}
.hero-copy {
  position: relative;
  z-index: 1;
  padding: 22vh 8vw 10vh;
  max-width: 820px;
}
.kicker, .vlabel {
  letter-spacing: 0.28em;
  font-size: 12px;
  margin: 0 0 12px;
  color: var(--gold);
}
.vlabel { color: var(--vermilion); font-family: var(--mono); }
h1, h2, h3 { font-family: var(--serif); font-weight: 700; line-height: 1.08; margin: 0 0 16px; word-break: keep-all; }
h1 { font-size: clamp(48px, 8vw, 108px); }
h2 { font-size: clamp(28px, 3.8vw, 44px); }
h3 { font-size: 22px; }
.lead {
  font-size: 17px;
  max-width: 38em;
  word-break: keep-all;
  overflow-wrap: anywhere;
  color: rgba(255, 250, 241, 0.9);
}
.hero-id {
  font-family: var(--mono);
  font-size: 12px;
  color: var(--gold);
  border-left: 3px solid var(--vermilion);
  padding-left: 12px;
}
.meta-row { display: flex; flex-wrap: wrap; gap: 8px; margin: 22px 0; }
.chip {
  border: 1px solid rgba(255, 250, 241, 0.35);
  padding: 3px 10px;
  font-size: 12px;
  letter-spacing: 0.08em;
}
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; }
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 10px 18px;
  border: 1px solid currentColor;
  font-size: 14px;
}
.btn-fill { background: var(--vermilion); color: #fffaf1; border-color: var(--vermilion); }
.btn-ghost { background: transparent; color: inherit; }

.wrap { width: min(1120px, calc(100% - 48px)); margin: 0 auto; padding: 96px 0; }
.section-head {
  display: grid;
  grid-template-columns: 150px 1fr;
  gap: 24px;
  margin-bottom: 40px;
  padding-bottom: 16px;
  border-bottom: 2px solid var(--vermilion);
}
.section-head p:last-child { color: var(--mute); margin: 0; }
.tri, .bench-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}
.doc {
  background: var(--rice-2);
  border: 1px solid var(--line);
  padding: 22px;
  min-height: 220px;
  box-shadow: inset 8px 0 0 var(--vermilion);
}
.doc.warn { box-shadow: inset 8px 0 0 var(--navy); }
.stamp {
  display: inline-block;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--vermilion);
  border: 1px solid var(--vermilion);
  padding: 1px 8px;
  margin-bottom: 10px;
}
.doc ul, .io ul, .rule-list { margin: 0; padding-left: 1.1em; }
.doc li, .io li, .rule-list li { margin: 0.35em 0; }

.alt { background: linear-gradient(180deg, #ebe3d4 0%, var(--rice) 100%); }

.row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
  align-items: center;
  margin-bottom: 72px;
}
.row.flip { direction: rtl; }
.row.flip > * { direction: ltr; }
.num {
  font-family: var(--serif);
  color: var(--vermilion);
  font-size: 28px;
  display: block;
  margin-bottom: 6px;
}
figure { margin: 0; }
figure img {
  width: 100%;
  height: 340px;
  object-fit: cover;
  box-shadow: var(--shadow);
}
figcaption { margin-top: 10px; font-size: 13px; color: var(--mute); }

.demo {
  margin-top: 20px;
  padding: 16px;
  border: 1px solid var(--navy);
  background: rgba(27, 42, 74, 0.04);
}
.demo-kicker { margin: 0; font-family: var(--mono); font-size: 11px; letter-spacing: 0.16em; color: var(--navy); }
.score {
  font-family: var(--serif);
  font-size: 56px;
  color: var(--vermilion);
  line-height: 1;
  margin: 8px 0;
}
.score.miss { color: var(--navy); }

.io {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}
.io > div {
  background: var(--rice-2);
  border-top: 6px solid var(--vermilion);
  padding: 20px 24px;
}

footer {
  background: var(--navy-2);
  color: var(--rice);
}
.footer-inner {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  padding: 36px 0;
  font-size: 13px;
}

@media (max-width: 960px) {
  .hero, .row, .section-head, .tri, .bench-grid, .io, .footer-inner { grid-template-columns: 1fr; }
  .hero { min-height: 100svh; }
  .hero-copy { padding: 140px 20px 48px; }
  .wrap { width: min(1120px, calc(100% - 32px)); }
  .mast-row { padding: 6px 16px 10px; }
  .docno { padding-left: 16px; }
  .nav-toggle { display: inline-flex; }
  .nav-links {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    padding: 12px 16px 18px;
    background: var(--rice-2);
    border-bottom: 1px solid var(--line);
  }
  .nav-links.open { display: flex; }
  figure img { height: 220px; }
}