:root {
  --bg: #ffffff;
  --fg: #1b1d22;
  --muted: #5d6270;
  --accent: #e8590c;
  --rule: #e4e6eb;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #14161a;
    --fg: #e9eaee;
    --muted: #a3a8b5;
    --accent: #ff8a3d;
    --rule: #2a2d34;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font: 16px/1.6 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}
main { max-width: 720px; margin: 0 auto; padding: 48px 16px 64px; }
header { display: flex; align-items: center; gap: 12px; margin-bottom: 32px; }
.mark {
  width: 40px; height: 40px; border-radius: 10px;
  background: linear-gradient(135deg, #ff8a3d, #e8590c);
  color: #fff; font-weight: 700; font-size: 22px;
  display: grid; place-items: center;
}
.brand { font-weight: 700; letter-spacing: 0.08em; }
h1 { font-size: 28px; line-height: 1.25; margin: 0 0 8px; }
h2 { font-size: 19px; margin: 32px 0 8px; }
p, li { color: var(--fg); }
.muted { color: var(--muted); }
a { color: var(--accent); }
footer {
  margin-top: 48px; padding-top: 16px; border-top: 1px solid var(--rule);
  font-size: 14px; color: var(--muted);
}
footer a { margin-right: 16px; }