:root {
  --bg: #ffffff;
  --fg: #1b1d2a;
  --muted: #5b6075;
  --accent: #3949ab;
  --card: #f3f4fa;
  --border: #dfe2ef;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #12131c;
    --fg: #e8e9f3;
    --muted: #a0a4bc;
    --accent: #8c9eff;
    --card: #1b1d2b;
    --border: #2d3045;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font: 16px/1.65 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}
header, main, footer { max-width: 760px; margin: 0 auto; padding: 0 16px; }
header { padding-top: 28px; display: flex; align-items: center; justify-content: space-between; gap: 12px; flex-wrap: wrap; }
.brand { font-weight: 700; font-size: 1.25rem; color: var(--fg); text-decoration: none; }
nav a { color: var(--muted); text-decoration: none; margin-left: 16px; }
nav a:hover { color: var(--accent); }
h1 { font-size: 2rem; line-height: 1.2; margin: 32px 0 8px; }
h2 { font-size: 1.25rem; margin: 32px 0 8px; }
p, li { color: var(--fg); }
.lead { color: var(--muted); font-size: 1.1rem; margin-top: 0; }
.muted { color: var(--muted); font-size: 0.9rem; }
a { color: var(--accent); }
ul { padding-left: 1.2rem; }
.card { background: var(--card); border: 1px solid var(--border); border-radius: 12px; padding: 16px 18px; margin: 16px 0; }
.card h3 { margin: 0 0 4px; font-size: 1.05rem; }
.card p { margin: 0; color: var(--muted); }
footer { padding: 32px 16px 48px; color: var(--muted); font-size: 0.9rem; border-top: 1px solid var(--border); margin-top: 48px; }
.btn { display: inline-block; background: var(--accent); color: var(--bg); padding: 10px 18px; border-radius: 10px; text-decoration: none; font-weight: 600; }
ol li { margin: 6px 0; }
.note { background: var(--card); border: 1px solid var(--border); border-radius: 12px; padding: 14px 18px; margin: 16px 0; }
.brand { display: inline-flex; align-items: center; gap: 10px; }
.brand img { border-radius: 8px; }
.hero-logo { display: block; margin-top: 32px; border-radius: 22px; box-shadow: 0 6px 24px rgba(57, 73, 171, .35); }
.hero-logo + h1 { margin-top: 20px; }