:root {
  --cement: #5c5e5a;
  --iron: #1a1c1e;
  --lead: #8a8e86;
  --seal: #2f6b45;
  --rust: #a33b1c;
  --paper: #e8e6df;
  --ink: #1a1c1e;
  --mute: #6a6e68;
  --serif: "Source Serif 4", "Noto Serif SC", serif;
  --sans: "Noto Sans SC", "PingFang SC", sans-serif;
  --mono: "IBM Plex Mono", ui-monospace, Menlo, monospace;
}
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
section[id] { scroll-margin-top: 70px; }
body { margin: 0; background: var(--paper); color: var(--ink); font-family: var(--sans); line-height: 1.7; }
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
.app-link { color: var(--rust); text-decoration: underline; text-underline-offset: 3px; }
button { font-family: inherit; cursor: pointer; }
code { font-family: var(--mono); }
.cement {
  pointer-events: none; position: fixed; inset: 0; z-index: 6; opacity: 0.14;
  background-image: url("images/texture.webp"); background-size: 360px; mix-blend-mode: multiply;
}
.skip { position: absolute; left: -999px; }
.skip:focus { left: 10px; top: 8px; z-index: 80; background: var(--seal); color: #fff; padding: 8px; }
.bar {
  position: sticky; top: 0; z-index: 40;
  display: flex; align-items: center; justify-content: space-between; gap: 12px;
  padding: 10px 22px; background: var(--iron); color: var(--paper); border-bottom: 4px solid var(--lead);
}
.brand { font-family: var(--serif); font-weight: 700; }
.brand small { display: block; font-family: var(--mono); font-size: 10px; letter-spacing: 0.14em; color: var(--lead); font-weight: 400; }
.nav-toggle { display: none; background: var(--lead); color: var(--iron); border: 0; padding: 6px 12px; }
.nav-links { display: flex; flex-wrap: wrap; gap: 14px; font-size: 14px; }
.nav-links a { color: #b0b4ae; }
.nav-links a.is-active, .nav-links a:hover { color: #fff; }
.nav-links .live { background: var(--seal); color: #fff; padding: 5px 12px; }
.hero { display: grid; grid-template-columns: 1.05fr 0.95fr; min-height: calc(100vh - 56px); }
.copy { padding: 8vh 32px; }
.hero figure { margin: 0; position: relative; }
.hero img { width: 100%; height: 100%; object-fit: cover; min-height: 100%; }
.hero figcaption { position: absolute; left: 0; right: 0; bottom: 0; padding: 12px; background: linear-gradient(transparent, rgba(26,28,30,0.9)); color: var(--paper); font-size: 13px; }
.kicker { font-family: var(--mono); letter-spacing: 0.14em; font-size: 11px; color: var(--rust); margin: 0 0 10px; }
h1, h2, h3 { font-family: var(--serif); margin: 0 0 12px; line-height: 1.12; }
h1 { font-size: clamp(36px, 5.4vw, 64px); }
h2 { font-size: clamp(24px, 3vw, 36px); }
.latch { margin: 20px 0; max-width: 440px; padding: 16px; background: #fff; border-left: 8px solid var(--rust); }
.latch.is-sealed { border-left-color: var(--seal); }
.claim { font-family: var(--serif); font-size: 20px; margin: 0 0 8px; }
#latch-toggle { background: var(--iron); color: #fff; border: 0; padding: 8px 14px; margin-top: 8px; }
.cta { display: flex; gap: 10px; flex-wrap: wrap; }
.btn { display: inline-flex; padding: 10px 18px; border: 2px solid var(--iron); font-weight: 700; }
.btn.fill { background: var(--iron); color: #fff; }
.btn.line { color: var(--iron); }
.w { width: min(1080px, calc(100% - 40px)); margin: 0 auto; padding: 80px 0; }
.iron { background: var(--iron); color: var(--paper); }
.iron .kicker { color: var(--lead); }
.tri { display: grid; grid-template-columns: 1fr 1fr 1fr; gap: 12px; margin-top: 20px; }
.tri article { background: #fff; padding: 16px; }
.iron .tri article { background: #242628; }
.tri ul, .io ul, #rules ol { margin: 0; padding-left: 1.1em; }
.pair { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; margin-top: 20px; }
.pair img { width: 100%; height: 220px; object-fit: cover; }
.pair figcaption { font-size: 13px; color: var(--mute); }
.iron .pair figcaption { color: #b0b4ae; }
#rules ol { background: #fff; padding: 16px 16px 16px 36px; border-left: 8px solid var(--rust); }
.io { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.io > div { background: #242628; padding: 16px; }
.url { margin-top: 18px; font-family: var(--mono); font-size: 13px; }
footer { padding: 20px 24px 36px; color: var(--mute); font-size: 13px; }
@media (max-width: 900px) {
  .hero, .tri, .pair, .io { grid-template-columns: 1fr; }
  .hero img { min-height: 42vh; height: 42vh; }
  .nav-toggle { display: inline-block; }
  .bar { flex-wrap: wrap; }
  .nav-links { display: none; width: 100%; flex-direction: column; background: #242628; padding: 12px; }
  .nav-links.open { display: flex; }
}