:root {
  --bg: #ffffff;
  --text: #1d1d1f;
  --muted: #6e6e73;
  --accent: #0a66d8;
  --rule: #e5e5ea;
  --card: #f5f5f7;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #000000;
    --text: #f5f5f7;
    --muted: #a1a1a6;
    --accent: #4da3ff;
    --rule: #2c2c2e;
    --card: #1c1c1e;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 17px/1.55 -apple-system, BlinkMacSystemFont, "SF Pro Text", "Helvetica Neue", Arial, sans-serif;
  -webkit-text-size-adjust: 100%;
}
main { max-width: 720px; margin: 0 auto; padding: 40px 20px 64px; }
header.brand { display: flex; align-items: center; gap: 12px; margin-bottom: 28px; }
header.brand img { width: 48px; height: 48px; border-radius: 11px; }
header.brand .name { font-weight: 600; font-size: 20px; }
header.brand .by { color: var(--muted); font-size: 14px; }
h1 { font-size: 32px; line-height: 1.2; margin: 0 0 8px; letter-spacing: -0.01em; }
h2 { font-size: 21px; margin: 32px 0 8px; }
p, li { margin: 0 0 10px; }
ul, ol { padding-left: 22px; }
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
.muted { color: var(--muted); }
.lead { font-size: 19px; }
.card { background: var(--card); border-radius: 14px; padding: 18px 20px; margin: 20px 0; }
nav.links { display: flex; flex-wrap: wrap; gap: 18px; margin-top: 40px; padding-top: 18px; border-top: 1px solid var(--rule); font-size: 15px; }
footer { color: var(--muted); font-size: 13px; margin-top: 12px; }