:root {
  --bg: #f6f8fb;
  --fg: #1c2430;
  --muted: #5b6676;
  --card: #ffffff;
  --accent: #2266d4;
  --border: #dde3ec;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #11161d;
    --fg: #e6ebf2;
    --muted: #9aa6b6;
    --card: #19202a;
    --accent: #6ea3ff;
    --border: #2a3442;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font: 16px/1.6 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}
main {
  max-width: 720px;
  margin: 0 auto;
  padding: 48px 16px 64px;
}
header {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 32px;
}
header img { width: 64px; height: 64px; }
h1 { margin: 0; font-size: 1.8rem; }
h2 { margin-top: 2rem; font-size: 1.2rem; }
.sub { margin: 0; color: var(--muted); }
.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 20px 24px;
}
a { color: var(--accent); }
footer {
  margin-top: 40px;
  padding-top: 16px;
  border-top: 1px solid var(--border);
  color: var(--muted);
  font-size: 0.9rem;
}