:root {
  --frost: #f4f7f5; --surface: #ffffff; --hairline: #d3dcd7;
  --ink: #18221f; --ink-muted: #55635e; --emerald: #2a715d;
}
@media (prefers-color-scheme: dark) {
  :root {
    --frost: #0e1413; --surface: #172020; --hairline: #27322f;
    --ink: #e8efec; --ink-muted: #9aa9a3; --emerald: #62c4a6;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0; background: var(--frost); color: var(--ink);
  font: 17px/1.6 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
}
main { max-width: 680px; margin: 0 auto; padding: 48px 20px 64px; }
header { display: flex; align-items: center; gap: 14px; margin-bottom: 32px; }
header img { width: 56px; height: 56px; border-radius: 13px; }
header a { color: inherit; text-decoration: none; font-size: 26px; font-weight: 600; }
h1 { font-size: 30px; line-height: 1.25; margin: 0 0 8px; }
h2 { font-size: 21px; margin: 36px 0 8px; }
p, li { color: var(--ink); }
.muted { color: var(--ink-muted); font-size: 15px; }
a { color: var(--emerald); }
.card {
  background: var(--surface); border: 1px solid var(--hairline); border-radius: 16px;
  padding: 4px 24px 20px; margin: 24px 0;
}
.lang { display: flex; gap: 12px; margin-bottom: 8px; font-size: 15px; }
nav { display: flex; gap: 20px; margin-top: 40px; font-size: 15px; }