:root { --bg: #ffffff; --text: #1d1d1f; --muted: #6e6e73; --card: #f5f5f7; --accent: #1f6fd1; }
@media (prefers-color-scheme: dark) {
  :root { --bg: #111418; --text: #f2f2f4; --muted: #a1a1a6; --card: #1c2027; --accent: #5aa2ff; }
}
* { box-sizing: border-box; }
body { margin: 0; background: var(--bg); color: var(--text);
       font: 17px/1.55 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif; }
main { max-width: 720px; margin: 0 auto; padding: 32px 16px 64px; }
header { display: flex; align-items: center; gap: 16px; margin-bottom: 24px; }
header img { width: 72px; height: 72px; border-radius: 16px; }
header h1 { margin: 0; font-size: 28px; line-height: 1.2; }
header p { margin: 2px 0 0; color: var(--muted); }
h2 { font-size: 21px; margin: 32px 0 8px; }
h3 { font-size: 17px; margin: 20px 0 4px; }
p, li { margin: 0 0 10px; }
a { color: var(--accent); }
.card { background: var(--card); border-radius: 14px; padding: 16px 18px; }
.muted { color: var(--muted); font-size: 15px; }
nav { margin-top: 40px; font-size: 15px; }