:root {
  --bg: #ffffff;
  --fg: #1a1a1a;
  --muted: #5a5a5a;
  --accent: #4a6cf7;
  --hr: #e5e5e5;
  --card: #f6f7f9;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f1115;
    --fg: #e8e8e8;
    --muted: #9aa0a6;
    --accent: #8aa1ff;
    --hr: #2a2d33;
    --card: #181b21;
  }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font: 16px/1.6 -apple-system, BlinkMacSystemFont, "Segoe UI", system-ui, sans-serif;
  color: var(--fg);
  background: var(--bg);
}
main { max-width: 720px; margin: 0 auto; padding: 48px 24px 80px; }
h1 { font-size: 2rem; margin: 0 0 4px; line-height: 1.2; }
h2 { font-size: 1.2rem; margin: 32px 0 8px; }
.updated { color: var(--muted); font-size: 0.9rem; margin: 0 0 32px; }
.nav { font-size: 0.9rem; margin-bottom: 24px; }
hr { border: 0; border-top: 1px solid var(--hr); margin: 40px 0; }
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
ul { padding-left: 22px; }
li { margin: 4px 0; }
.card {
  background: var(--card);
  border: 1px solid var(--hr);
  border-radius: 10px;
  padding: 18px 22px;
  margin: 14px 0;
}
.card h3 { margin: 0 0 6px; font-size: 1.05rem; }
.card p { margin: 0; color: var(--muted); font-size: 0.95rem; }
footer { color: var(--muted); font-size: 0.85rem; margin-top: 56px; }