:root {
  --bg: #f6f7f9;
  --surface: #ffffff;
  --text: #12151a;
  --dim: #5b6472;
  --border: #e3e7ee;
  --accent: #2563eb;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0e1116; --surface: #171b22; --text: #f2f4f8;
    --dim: #a7b0bf; --border: #28303c; --accent: #5b8cff;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0;
  padding: 40px 20px 80px;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.65 -apple-system, "Helvetica Neue", Arial, sans-serif;
}
main { max-width: 680px; margin: 0 auto; }
header { display: flex; align-items: center; gap: 16px; margin-bottom: 8px; }
.icon {
  width: 64px; height: 64px; border-radius: 15px; flex: none;
  background: linear-gradient(135deg, #3b82f6, #1d4ed8);
  display: grid; place-items: center; font-size: 30px;
}
h1 { font-size: 26px; margin: 0; letter-spacing: -0.4px; }
.sub { color: var(--dim); margin: 2px 0 0; }
h2 { font-size: 18px; margin: 34px 0 10px; letter-spacing: -0.2px; }
p, li { color: var(--text); }
.card {
  background: var(--surface); border: 1px solid var(--border);
  border-radius: 16px; padding: 18px 20px; margin-top: 14px;
}
a { color: var(--accent); }
footer { color: var(--dim); font-size: 14px; margin-top: 48px; }
ul { padding-left: 20px; }