:root {
  --bg: #ffffff;
  --text: #1a1a1a;
  --muted: #666;
  --accent: #2563eb;
  --border: #e5e7eb;
  --code-bg: #f5f5f7;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f1115;
    --text: #ececec;
    --muted: #9aa0a6;
    --accent: #60a5fa;
    --border: #2a2f3a;
    --code-bg: #191c22;
  }
}
* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  background: var(--bg);
  color: var(--text);
  font: 16px/1.7 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
    "Helvetica Neue", Arial, "PingFang SC", "Hiragino Sans GB",
    "Microsoft YaHei", sans-serif;
  padding: 2rem 1rem 4rem;
}
.container { max-width: 780px; margin: 0 auto; }
.hero { border-bottom: 1px solid var(--border); padding-bottom: 1.25rem; margin-bottom: 1.5rem; }
h1 { font-size: 2rem; margin: 0 0 .4rem; }
h2 { font-size: 1.3rem; margin: 2rem 0 .6rem; color: var(--accent); }
h3 { font-size: 1.05rem; margin: 1.4rem 0 .4rem; }
.tagline { color: var(--muted); margin: 0; }
.muted { color: var(--muted); font-size: .9rem; }
.updated { color: var(--muted); font-size: .9rem; margin-bottom: 1.5rem; }
p, li { margin: 0 0 .8rem; }
ul, ol { padding-left: 1.4rem; }
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
code { background: var(--code-bg); padding: .1em .35em; border-radius: 4px; font-size: .95em; }
hr { border: none; border-top: 1px solid var(--border); margin: 2rem 0; }
table { width: 100%; border-collapse: collapse; margin: .8rem 0 1.2rem; font-size: .95rem; }
th, td { border: 1px solid var(--border); padding: .55rem .7rem; text-align: left; vertical-align: top; }
th { background: var(--code-bg); }
.nav { margin-bottom: 1rem; }
.nav a { margin-right: 1rem; }
footer { margin-top: 3rem; border-top: 1px solid var(--border); padding-top: 1rem; }