:root {
  color-scheme: light dark;
  --bg: #ffffff;
  --fg: #1a1a1a;
  --muted: #5a5a5a;
  --accent: #0b5fff;
  --border: #e5e5e5;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0a0a0b;
    --fg: #f0f0f0;
    --muted: #a0a0a0;
    --accent: #6fa1ff;
    --border: #2a2a2a;
  }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  line-height: 1.6;
  font-size: 16px;
}
main { max-width: 760px; margin: 0 auto; padding: 40px 24px 80px; }
header { border-bottom: 1px solid var(--border); padding-bottom: 24px; margin-bottom: 32px; }
h1 { font-size: 28px; margin: 0 0 8px; font-weight: 700; letter-spacing: -0.01em; }
h2 { font-size: 20px; margin: 32px 0 12px; font-weight: 600; }
h3 { font-size: 16px; margin: 20px 0 8px; font-weight: 600; }
p, li { color: var(--fg); }
.muted { color: var(--muted); font-size: 14px; }
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
ul { padding-left: 22px; }
li { margin-bottom: 6px; }
.toc { margin: 16px 0 0; font-size: 14px; }
.toc a { margin-right: 14px; }
footer { margin-top: 60px; padding-top: 24px; border-top: 1px solid var(--border); font-size: 13px; color: var(--muted); }