:root {
  --bg: #f6f7fb;
  --card: #ffffff;
  --text: #0f172a;
  --muted: #64748b;
  --border: #e2e8f0;
  --brand: #4f46e5;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0b1020;
    --card: #121a2e;
    --text: #e2e8f0;
    --muted: #94a3b8;
    --border: #1f2a44;
    --brand: #818cf8;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.6 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}
main { max-width: 760px; margin: 0 auto; padding: 32px 16px 64px; }
header { display: flex; align-items: center; gap: 12px; margin-bottom: 24px; }
header img { width: 44px; height: 44px; border-radius: 10px; }
header a { color: var(--text); text-decoration: none; font-weight: 700; font-size: 20px; }
h1 { font-size: 30px; line-height: 1.2; margin: 0 0 8px; }
h2 { font-size: 20px; margin: 32px 0 8px; }
h3 { font-size: 17px; margin: 24px 0 4px; }
p, li { color: var(--text); }
.muted { color: var(--muted); }
a { color: var(--brand); }
.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 20px;
  margin: 16px 0;
}
.lang { font-size: 14px; }
hr { border: 0; border-top: 1px solid var(--border); margin: 48px 0; }
footer { margin-top: 48px; font-size: 14px; color: var(--muted); }