:root {
  --foil: #e7edf0;
  --card: #f7fafb;
  --ink: #1b2a32;
  --mute: #5c6d75;
  --silver: #8aa0aa;
  --void: #c43a3a;
  --ok: #2f7d5b;
  --line: rgba(27, 42, 50, 0.12);
  --sans: "IBM Plex 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: 84px; }

body {
  margin: 0;
  color: var(--ink);
  background: var(--foil);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.7;
}

img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
.app-link { color: #1a6b8a; text-decoration: underline; text-underline-offset: 3px; }
button { font-family: inherit; cursor: pointer; }
code { font-family: var(--mono); font-size: 0.88em; background: rgba(196,58,58,0.08); padding: 0.05em 0.4em; }

.foil {
  pointer-events: none;
  position: fixed;
  inset: 0;
  z-index: 4;
  opacity: 0.2;
  background-image: url("images/texture.webp");
  background-size: 360px auto;
  mix-blend-mode: multiply;
}

.pockets {
  pointer-events: none;
  position: fixed;
  inset: 0;
  z-index: 3;
  opacity: 0.07;
  background-image: radial-gradient(circle at 20px 20px, transparent 12px, rgba(27,42,50,0.55) 13px);
  background-size: 56px 40px;
}

.skip { position: absolute; left: -999px; }
.skip:focus { left: 12px; top: 12px; z-index: 70; background: #fff; padding: 8px 12px; }

.nav {
  position: sticky;
  top: 0;
  z-index: 50;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 12px 28px;
  background: rgba(247, 250, 251, 0.88);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--line);
}

.brand { display: flex; align-items: center; gap: 10px; font-weight: 600; letter-spacing: 0.04em; }
.brand small { display: block; font-family: var(--mono); font-weight: 400; font-size: 10px; letter-spacing: 0.16em; color: var(--mute); }
.seal {
  width: 36px; height: 28px;
  border: 1px solid var(--silver);
  border-radius: 8px;
  display: grid; place-items: center;
  font-size: 13px;
  background: linear-gradient(180deg, #fff, #d5e0e5);
}

.nav-toggle { display: none; background: transparent; border: 1px solid var(--ink); color: var(--ink); padding: 6px 12px; }
.nav-links { display: flex; gap: 16px; font-size: 13px; }
.nav-links a { color: var(--mute); border-bottom: 2px solid transparent; padding-bottom: 2px; }
.nav-links a.is-active, .nav-links a:hover { color: var(--ink); border-bottom-color: var(--void); }
.nav-links a.live { color: #fff; background: var(--ink); border: 0; padding: 6px 12px; }

.hero {
  display: grid;
  grid-template-columns: 0.92fr 1.08fr;
  min-height: calc(100vh - 70px);
}
.hero-copy { padding: 8vh 6vw; display: flex; flex-direction: column; justify-content: center; }
.hero-frame { margin: 0; position: relative; }
.hero-frame img { width: 100%; height: 100%; object-fit: cover; min-height: 540px; }
.hero-frame figcaption {
  position: absolute; left: 12px; right: 12px; bottom: 12px;
  background: rgba(27,42,50,0.78); color: #fff; padding: 8px 12px; font-size: 13px;
}

.kicker, .vlabel { font-family: var(--mono); letter-spacing: 0.2em; font-size: 11px; color: var(--void); margin: 0 0 12px; }
h1, h2, h3 { font-weight: 600; line-height: 1.08; margin: 0 0 14px; letter-spacing: -0.03em; }
h1 { font-size: clamp(38px, 6vw, 76px); }
h2 { font-size: clamp(24px, 3.2vw, 38px); }
h3 { font-size: 20px; }
.lead { max-width: 42em; color: #314249; }

.meta-row { display: flex; flex-wrap: wrap; gap: 8px; margin: 20px 0; }
.chip { border: 1px solid var(--line); padding: 4px 10px; font-size: 12px; font-family: var(--mono); background: #fff; border-radius: 999px; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; }
.btn { display: inline-flex; align-items: center; justify-content: center; padding: 10px 18px; border: 1px solid currentColor; font-size: 14px; }
.btn-fill { background: var(--void); color: #fff; border-color: var(--void); }
.btn-ghost { background: #fff; }

.wrap { width: min(1120px, calc(100% - 48px)); margin: 0 auto; padding: 80px 0; }
.section-head { display: grid; grid-template-columns: 150px 1fr; gap: 22px; margin-bottom: 32px; }
.section-head p:last-child { color: var(--mute); margin: 0; }

.pocket-grid, .bench-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 14px; }
.pocket, .bench, .io-grid > div {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 20px;
  box-shadow: inset 0 8px 16px rgba(255,255,255,0.7);
}
.pocket.empty { outline: 2px solid var(--void); outline-offset: -6px; }
.stamp { font-family: var(--mono); font-size: 11px; letter-spacing: 0.14em; color: var(--void); }
.alt { background: #dfe7eb; }

.lane {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
  align-items: center;
  margin-bottom: 40px;
}
.lane.rev { direction: rtl; }
.lane.rev > * { direction: ltr; }
.lane figure { margin: 0; border: 1px solid var(--line); border-radius: 14px; overflow: hidden; background: #fff; }
.lane img { width: 100%; height: 240px; object-fit: cover; }
.lane figcaption { padding: 10px 14px; font-size: 13px; color: var(--mute); }
.num { font-family: var(--mono); font-size: 12px; color: var(--void); letter-spacing: 0.12em; }

.card-demo { margin-top: 14px; padding: 14px; border-radius: 14px; background: #fff; border: 1px solid var(--line); }
.lock-ok { color: var(--ok); font-weight: 600; }
.lock-warn { color: var(--void); font-weight: 600; }

.rule-list { margin: 0; padding-left: 22px; }
.rule-list li { margin-bottom: 10px; }
.io-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
footer { border-top: 1px solid var(--line); background: #fff; }
.footer-inner { display: flex; justify-content: space-between; gap: 16px; padding: 28px 0 48px; color: var(--mute); font-size: 14px; }

@media (max-width: 900px) {
  .nav { padding: 12px 16px; flex-wrap: wrap; }
  .nav-toggle { display: inline-flex; margin-left: auto; background: #fff; position: relative; z-index: 60; }
  .nav-links { display: none; flex-direction: column; width: 100%; padding: 8px 0 12px; }
  .nav-links.open { display: flex; }
  .hero, .lane, .lane.rev, .section-head, .pocket-grid, .bench-grid, .io-grid, .footer-inner {
    grid-template-columns: 1fr; direction: ltr;
  }
  .hero-copy { padding: 36px 20px 24px; }
  .hero-frame img { min-height: 240px; }
  .wrap { width: min(1120px, calc(100% - 28px)); padding: 52px 0; }
}