:root {
  --bg: #f4f6fa;
  --card: #ffffff;
  --text: #1f2a3c;
  --muted: #5d6b82;
  --accent: #2f7de1;
  --line: #e1e6ef;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #141a24;
    --card: #1d2532;
    --text: #e8edf5;
    --muted: #9aa8bd;
    --accent: #4ea8ff;
    --line: #2c3646;
  }
}
* { 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: 32px 16px 56px; }
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: 26px; }
header p { margin: 2px 0 0; color: var(--muted); }
nav { display: flex; gap: 16px; margin-bottom: 20px; }
nav a { color: var(--accent); text-decoration: none; font-weight: 600; }
nav a[aria-current] { color: var(--text); }
.card { background: var(--card); border: 1px solid var(--line); border-radius: 14px; padding: 8px 24px 20px; }
h2 { font-size: 19px; margin: 24px 0 6px; }
p, li { color: var(--text); }
.muted { color: var(--muted); font-size: 14px; }
a { color: var(--accent); }
footer { margin-top: 24px; color: var(--muted); font-size: 14px; text-align: center; }