:root {
  color-scheme: light dark;
  --bg: #f5f5f7;
  --card: #ffffff;
  --text: #1d1d1f;
  --muted: #6e6e73;
  --accent: #0a9396;
  --line: #e5e5ea;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #000000;
    --card: #1c1c1e;
    --text: #f5f5f7;
    --muted: #98989d;
    --accent: #3cc8c8;
    --line: #38383a;
  }
}
* { 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 16px 64px; }
header { display: flex; align-items: center; gap: 14px; margin-bottom: 28px; }
header img { width: 56px; height: 56px; border-radius: 13px; }
header a { color: inherit; text-decoration: none; font-weight: 700; font-size: 20px; }
h1 { font-size: 34px; line-height: 1.15; margin: 0 0 8px; letter-spacing: -0.02em; }
h2 { font-size: 21px; margin: 32px 0 8px; }
p, li { color: var(--text); }
.lead { color: var(--muted); font-size: 19px; margin-top: 0; }
.muted { color: var(--muted); font-size: 15px; }
.card { background: var(--card); border-radius: 20px; padding: 20px 22px; margin: 16px 0; }
.card h2 { margin-top: 0; }
a { color: var(--accent); }
ul { padding-left: 22px; }
details { background: var(--card); border-radius: 16px; padding: 14px 18px; margin: 10px 0; }
summary { font-weight: 600; cursor: pointer; }
details p { margin-bottom: 0; }
nav { display: flex; flex-wrap: wrap; gap: 8px 18px; margin-top: 40px; padding-top: 18px; border-top: 1px solid var(--line); font-size: 15px; }