:root {
  --bg: #f5f6f8;
  --surface: #ffffff;
  --text: #0f172a;
  --muted: #5b6474;
  --border: #e3e6eb;
  --accent: #2563eb;
  color-scheme: light dark;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0b0f14;
    --surface: #131a22;
    --text: #e6e9ee;
    --muted: #97a1b0;
    --border: #232c37;
    --accent: #60a5fa;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.6 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
}
main { max-width: 720px; margin: 0 auto; padding: 48px 20px 64px; }
header { display: flex; align-items: center; gap: 16px; margin-bottom: 32px; }
header img { width: 64px; height: 64px; border-radius: 15px; }
header a { color: inherit; text-decoration: none; }
h1 { font-size: 28px; line-height: 1.2; margin: 0; }
h2 { font-size: 19px; margin: 32px 0 8px; }
p, li { color: var(--text); }
.muted { color: var(--muted); }
a { color: var(--accent); }
.card { background: var(--surface); border: 1px solid var(--border); border-radius: 16px; padding: 20px 24px; margin: 16px 0; }
nav { margin-top: 40px; padding-top: 16px; border-top: 1px solid var(--border); font-size: 14px; }
nav a { margin-right: 16px; }
ul { padding-left: 20px; }