:root {
  --bg: #f4f7fb;
  --surface: #ffffff;
  --text: #162033;
  --muted: #5a6a82;
  --accent: #0078D4;
  --accent-dark: #005A9E;
  --border: #e4eaf2;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #1A2332;
    --surface: #222e41;
    --text: #eaf0f8;
    --muted: #9fb0c8;
    --accent: #5db4ff;
    --accent-dark: #8ec5ff;
    --border: #33425b;
  }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.65 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}
a { color: var(--accent-dark); }
header, main, footer { max-width: 880px; margin: 0 auto; padding: 0 16px; }
header {
  display: flex; align-items: center; gap: 12px; flex-wrap: wrap;
  padding-top: 20px; padding-bottom: 20px;
  border-bottom: 1px solid var(--border);
}
header img { width: 44px; height: 44px; }
header .brand { font-weight: 700; font-size: 20px; text-decoration: none; color: var(--text); }
header nav { margin-left: auto; display: flex; gap: 16px; flex-wrap: wrap; font-size: 15px; }
header nav a { text-decoration: none; }
main { padding-top: 32px; padding-bottom: 48px; }
h1 { font-size: clamp(28px, 5vw, 40px); line-height: 1.2; margin: 0 0 12px; }
h2 { font-size: 22px; margin: 36px 0 8px; }
h3 { font-size: 18px; margin: 24px 0 6px; }
.lead { font-size: 18px; color: var(--muted); max-width: 680px; }
.cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 14px; margin: 24px 0; }
.card { background: var(--surface); border: 1px solid var(--border); border-radius: 12px; padding: 16px; }
.card h3 { margin-top: 0; }
.note { background: var(--surface); border-left: 4px solid var(--accent); padding: 12px 16px; border-radius: 6px; }
.lang { border-top: 1px solid var(--border); margin-top: 48px; padding-top: 8px; }
footer {
  border-top: 1px solid var(--border);
  padding-top: 20px; padding-bottom: 32px;
  font-size: 14px; color: var(--muted);
}
footer a { margin-right: 14px; }