:root {
  --bg: #f7f8fb;
  --surface: #ffffff;
  --text: #16202e;
  --muted: #5b6676;
  --line: #e2e6ee;
  --accent: #2f5bd8;
  --accent-soft: #e8eefc;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f141c;
    --surface: #161d28;
    --text: #e6ebf3;
    --muted: #9aa6b8;
    --line: #253043;
    --accent: #7c9cff;
    --accent-soft: #1d2a47;
  }
}
* { box-sizing: border-box; }
html, body { margin: 0; background: var(--bg); color: var(--text); }
body { font: 16px/1.6 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif; }
a { color: var(--accent); }
.wrap { max-width: 760px; margin: 0 auto; padding: 0 20px; }
header { border-bottom: 1px solid var(--line); background: var(--surface); }
header .wrap { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.brand { font-weight: 800; letter-spacing: .04em; font-size: 20px; color: var(--text); text-decoration: none; }
.brand span { color: var(--accent); }
nav a { margin-left: 18px; color: var(--muted); text-decoration: none; font-size: 15px; }
nav a:hover { color: var(--text); }
main { padding: 48px 0 64px; }
h1 { font-size: 34px; line-height: 1.2; margin: 0 0 12px; }
h2 { font-size: 20px; margin: 32px 0 8px; }
.lead { font-size: 19px; color: var(--muted); margin: 0 0 28px; }
.systems { display: grid; grid-template-columns: repeat(auto-fit, minmax(210px, 1fr)); gap: 12px; margin: 24px 0; }
.card { background: var(--surface); border: 1px solid var(--line); border-radius: 12px; padding: 14px 16px; }
.card b { display: block; margin-bottom: 2px; }
.card span { color: var(--muted); font-size: 14px; }
.note { background: var(--accent-soft); border-radius: 10px; padding: 12px 16px; }
footer { border-top: 1px solid var(--line); color: var(--muted); font-size: 14px; padding: 20px 0 32px; }
@media (max-width: 520px) { h1 { font-size: 28px; } nav a { margin-left: 12px; } }