:root {
  --sea: #16352e;
  --sea-2: #1f4a40;
  --foam: #e7efe8;
  --hemp: #8a5a32;
  --brass: #c4a46a;
  --mesh: #2f6b5a;
  --warn: #c45a2a;
  --ok: #3d8f6e;
  --ink: #14241f;
  --mute: #5c6f68;
  --line: rgba(20, 36, 31, 0.14);
  --shadow: 0 22px 48px rgba(22, 53, 46, 0.28);
  --serif: "Noto Serif SC", "Songti 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: 76px; }
body {
  margin: 0;
  color: var(--ink);
  background: var(--foam);
  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 { color: var(--brass); text-decoration: underline; text-underline-offset: 3px; }
button { font-family: inherit; cursor: pointer; }
code {
  font-family: var(--mono);
  font-size: 0.92em;
  background: rgba(47, 107, 90, 0.1);
  padding: 0.05em 0.35em;
}
.grain {
  pointer-events: none;
  position: fixed;
  inset: 0;
  z-index: 40;
  opacity: 0.12;
  background-image: url("images/texture.webp");
  background-size: 640px auto;
  mix-blend-mode: multiply;
}
.skip { position: absolute; left: -999px; }
.skip:focus { left: 12px; top: 12px; z-index: 60; background: #fff; padding: 8px 12px; }
.nav {
  position: sticky;
  top: 0;
  z-index: 30;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 12px 28px;
  background: rgba(231, 239, 232, 0.9);
  backdrop-filter: blur(12px);
  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-weight: 400;
  font-size: 10px;
  letter-spacing: 0.14em;
  color: var(--mute);
}
.seal {
  width: 36px;
  height: 36px;
  display: grid;
  place-items: center;
  border: 1px solid var(--mesh);
  color: var(--mesh);
  font-family: var(--serif);
}
.nav-toggle {
  display: none;
  background: transparent;
  border: 1px solid var(--mesh);
  color: var(--mesh);
  padding: 6px 12px;
}
.nav-links { display: flex; gap: 18px; font-size: 14px; }
.nav-links a { color: var(--mute); border-bottom: 1px solid transparent; padding-bottom: 2px; }
.nav-links a.is-active,
.nav-links a:hover { color: var(--mesh); border-bottom-color: var(--brass); }
.nav-links .live {
  color: var(--foam);
  background: var(--mesh);
  border: 0;
  padding: 6px 12px;
}
.hero {
  position: relative;
  min-height: 94vh;
  display: grid;
  align-items: end;
  overflow: hidden;
  color: var(--foam);
}
.hero img { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; }
.hero::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(22, 53, 46, 0.12) 0%, rgba(22, 53, 46, 0.55) 50%, rgba(14, 32, 28, 0.92) 100%);
}
.hero-inner { position: relative; z-index: 1; padding: 8vh 8vw 9vh; max-width: 920px; }
.kicker, .vlabel {
  font-family: var(--mono);
  letter-spacing: 0.2em;
  font-size: 12px;
  color: var(--brass);
  margin: 0 0 12px;
}
.vlabel { color: var(--mesh); }
h1, h2, h3 {
  font-family: var(--serif);
  font-weight: 700;
  line-height: 0.98;
  margin: 0 0 16px;
  letter-spacing: -0.03em;
}
h1 { font-size: clamp(48px, 8.5vw, 100px); }
h2 { font-size: clamp(28px, 4vw, 44px); line-height: 1.15; }
h3 { font-size: 22px; line-height: 1.25; }
.lead { font-size: 18px; max-width: 42em; color: rgba(231, 239, 232, 0.9); }
.meta-row { display: flex; flex-wrap: wrap; gap: 8px; margin: 22px 0; }
.chip {
  border: 1px solid rgba(196, 164, 106, 0.45);
  padding: 4px 10px;
  font-size: 12px;
  font-family: var(--mono);
}
.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(--brass); color: var(--sea); border-color: var(--brass); }
.btn-ghost { background: transparent; color: inherit; }
.wrap { width: min(1120px, calc(100% - 48px)); margin: 0 auto; padding: 88px 0; }
.section-head {
  display: grid;
  grid-template-columns: 150px 1fr;
  gap: 24px;
  margin-bottom: 40px;
}
.section-head p:last-child { color: var(--mute); margin: 0; }
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.card {
  background: rgba(255, 255, 255, 0.55);
  border: 1px solid var(--line);
  padding: 22px;
  min-height: 220px;
}
.stamp {
  display: inline-block;
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--mesh);
  border: 1px solid var(--mesh);
  padding: 2px 8px;
  margin-bottom: 10px;
  font-family: var(--mono);
}
.card ul, .io-grid ul, .rule-list { margin: 0; padding-left: 1.1em; }
.card li, .io-grid li, .rule-list li { margin: 0.35em 0; }
.alt { background: linear-gradient(180deg, #d5e4da 0%, var(--foam) 100%); }
.step {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 36px;
  align-items: center;
  margin-bottom: 72px;
}
.step.reverse { direction: rtl; }
.step.reverse > * { direction: ltr; }
.num {
  font-family: var(--mono);
  font-size: 13px;
  letter-spacing: 0.2em;
  color: var(--hemp);
  display: block;
  margin-bottom: 8px;
}
figure { margin: 0; }
figure img {
  width: 100%;
  height: 320px;
  object-fit: cover;
  box-shadow: var(--shadow);
}
figcaption { margin-top: 10px; font-size: 13px; color: var(--mute); font-style: italic; }
.gauge-demo {
  margin-top: 22px;
  padding: 16px;
  border: 1px dashed var(--mesh);
  background: rgba(47, 107, 90, 0.06);
}
.clock-label {
  margin: 0 0 12px;
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--mute);
  font-family: var(--mono);
}
.slider {
  display: grid;
  grid-template-columns: 90px 1fr 72px;
  gap: 10px;
  align-items: center;
  font-size: 13px;
  color: var(--mute);
}
.slider input { width: 100%; accent-color: var(--mesh); }
.slider span { font-family: var(--mono); color: var(--mesh); }
.tri-state { margin: 12px 0 0; font-family: var(--mono); font-size: 13px; }
.tri-state.warn { color: var(--warn); }
.tri-state.ok { color: var(--ok); }
.bench-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.bench { padding: 18px; background: #fff; border: 1px solid var(--line); }
.bench h3 { font-size: 18px; margin-bottom: 8px; }
.bench p { margin: 0; color: var(--mute); font-size: 14px; }
.rule-list { font-size: 17px; max-width: 46em; }
.rule-list li { border-left: 2px solid var(--mesh); padding: 8px 0 8px 14px; }
.io-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 28px; }
footer { border-top: 1px solid var(--line); background: var(--sea); color: #c9d9d2; }
.footer-inner {
  padding: 32px 0;
  display: flex;
  justify-content: space-between;
  gap: 16px;
  font-size: 13px;
}
@media (max-width: 860px) {
  .nav-toggle { display: block; }
  .nav-links {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    flex-direction: column;
    padding: 12px 20px 18px;
    background: var(--foam);
    border-bottom: 1px solid var(--line);
  }
  .nav-links.open { display: flex; }
  .section-head, .grid-3, .step, .step.reverse, .io-grid, .bench-grid {
    grid-template-columns: 1fr;
    direction: ltr;
    display: grid;
  }
  .footer-inner { display: flex; flex-direction: column; }
  h1 { font-size: 44px; }
  figure img { height: 220px; }
  .wrap { width: min(1120px, calc(100% - 32px)); padding: 56px 0; }
  .slider { grid-template-columns: 1fr; }
}