:root {
  --paper: #f8f7f3;
  --card: #ffffff;
  --ink: #111111;
  --muted: #5c5a55;
  --line: #e4e1d9;
  --chip: #efede6;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root {
    --paper: #121211;
    --card: #1b1b19;
    --ink: #f4f2ec;
    --muted: #a8a59c;
    --line: #2e2d2a;
    --chip: #24231f;
    color-scheme: dark;
  }
  .mark { filter: invert(1); }
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font: 17px/1.6 -apple-system, BlinkMacSystemFont, "SF Pro Text", "Inter", "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}
a { color: inherit; text-underline-offset: 3px; }
.wrap { max-width: 960px; margin: 0 auto; padding: 0 20px; }

header.top { padding: 20px 0; }
header.top .wrap { display: flex; align-items: center; justify-content: space-between; gap: 16px; }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; font-size: 19px; letter-spacing: -0.01em; text-decoration: none; }
.brand img { width: 36px; height: 36px; }
nav.top a { color: var(--muted); text-decoration: none; margin-left: 18px; font-size: 15px; }
nav.top a:hover { color: var(--ink); }

.hero { padding-top: 56px; padding-bottom: 40px; text-align: center; }
.hero .mark { width: 112px; height: 112px; }
.chip { display: inline-block; margin: 20px 0 8px; padding: 5px 12px; border-radius: 999px; background: var(--chip); border: 1px solid var(--line); color: var(--muted); font-size: 14px; }
h1 { font-size: clamp(34px, 6vw, 54px); line-height: 1.08; letter-spacing: -0.03em; margin: 12px auto 16px; max-width: 14ch; }
.lead { font-size: clamp(18px, 2.4vw, 21px); color: var(--muted); max-width: 36ch; margin: 0 auto; }

.features { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 16px; padding-top: 32px; padding-bottom: 24px; }
.card { background: var(--card); border: 1px solid var(--line); border-radius: 18px; padding: 22px 22px 18px; }
.card h2 { font-size: 18px; margin: 0 0 6px; letter-spacing: -0.01em; }
.card p { margin: 0; color: var(--muted); font-size: 16px; }

.cta { text-align: center; padding-top: 40px; padding-bottom: 64px; }
.cta h2 { font-size: 26px; letter-spacing: -0.02em; margin: 0 0 8px; }
.cta p { color: var(--muted); margin: 0 0 20px; }
.button { display: inline-block; padding: 12px 22px; border-radius: 12px; background: var(--ink); color: var(--paper); text-decoration: none; font-weight: 600; }

footer { border-top: 1px solid var(--line); padding: 24px 0 40px; color: var(--muted); font-size: 14px; }
footer .wrap { display: flex; flex-wrap: wrap; gap: 8px 20px; justify-content: space-between; }
footer a { color: var(--muted); }

.doc { max-width: 720px; padding-top: 24px; padding-bottom: 64px; }
.doc h1 { text-align: left; max-width: none; font-size: clamp(30px, 5vw, 40px); margin: 16px 0 4px; }
.doc .updated { color: var(--muted); margin: 0 0 28px; }
.doc h2 { font-size: 21px; margin: 32px 0 8px; letter-spacing: -0.01em; }
.doc p, .doc li { color: var(--ink); }
.doc ul { padding-left: 22px; }
.doc li { margin: 4px 0; }

@media (max-width: 520px) {
  nav.top a { margin-left: 12px; }
  .hero { padding-top: 32px; }
}