:root {
  --bg: #0f1115;
  --panel: #171a21;
  --text: #e6e8ec;
  --muted: #8a93a3;
  --accent: #6c8cff;
  --border: #2a2f3a;
}
:root.light { --bg: #f4f6fa; --panel: #fff; --text: #1a1d24; --muted: #6b7280; --border: #e2e6ee; }
* { box-sizing: border-box; }
body {
  margin: 0; font-family: -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif;
  background: var(--bg); color: var(--text); line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}
header.top {
  display: flex; justify-content: space-between; align-items: center;
  padding: 16px 28px; border-bottom: 1px solid var(--border);
  background: var(--panel); position: sticky; top: 0; z-index: 10;
}
.brand { display: flex; align-items: center; gap: 10px; color: var(--text); text-decoration: none; font-weight: 600; }
.brand .logo {
  width: 30px; height: 30px; border-radius: 8px;
  background: linear-gradient(135deg, var(--accent), #8a6cff);
  display: inline-flex; align-items: center; justify-content: center; color: white;
}
nav a { color: var(--muted); text-decoration: none; margin-left: 20px; font-size: 14px; }
nav a:hover { color: var(--accent); }
main { max-width: 800px; margin: 0 auto; padding: 40px 24px; }
h1 { font-size: 28px; margin: 0 0 16px; }
h2 { font-size: 18px; margin: 32px 0 12px; color: var(--text); }
.lead { font-size: 16px; color: var(--muted); }
ul { padding-left: 22px; }
li { margin: 6px 0; }
code {
  background: var(--panel); border: 1px solid var(--border);
  padding: 1px 6px; border-radius: 4px; font-size: 13px;
}
a { color: var(--accent); }
footer {
  text-align: center; padding: 30px 20px; color: var(--muted);
  border-top: 1px solid var(--border); margin-top: 40px; font-size: 13px;
}
footer a { color: var(--muted); margin: 0 4px; }
footer a:hover { color: var(--accent); }