:root {
  color-scheme: light dark;
  --bg: #f4f5fa;
  --card: #ffffff;
  --text: #101322;
  --muted: #5a6275;
  --accent: #008c66;
  --border: #e3e5ee;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0a0b12;
    --card: #14161f;
    --text: #f3f4f9;
    --muted: #9ba2b4;
    --accent: #2bd69e;
    --border: #232633;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.6 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
}
main { max-width: 720px; margin: 0 auto; padding: 40px 16px 64px; }
header { margin-bottom: 28px; }
.brand { color: var(--accent); font-weight: 700; letter-spacing: .08em; font-size: 13px; text-transform: uppercase; }
h1 { font-size: 30px; line-height: 1.2; margin: 6px 0 8px; }
h2 { font-size: 19px; margin: 28px 0 8px; }
p, li { color: var(--muted); }
strong { color: var(--text); }
a { color: var(--accent); }
section.card { background: var(--card); border: 1px solid var(--border); border-radius: 18px; padding: 4px 20px 16px; margin-top: 16px; }
nav a { margin-right: 16px; }
footer { margin-top: 40px; font-size: 14px; color: var(--muted); }
section.card h2:first-child { margin-top: 16px; }