:root {
  --bg: #f5f5f7; --card: #ffffff; --text: #1d1d1f; --secondary: #6e6e73;
  --accent: #2f4a7a; --line: #d2d2d7;
  color-scheme: light dark;
}
@media (prefers-color-scheme: dark) {
  :root { --bg: #000000; --card: #1c1c1e; --text: #f5f5f7; --secondary: #a1a1a6; --accent: #8fb0ff; --line: #38383a; }
}
* { box-sizing: border-box; }
body {
  margin: 0; background: var(--bg); color: var(--text);
  font: 17px/1.55 -apple-system, BlinkMacSystemFont, "SF Pro Text", "Helvetica Neue", Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
}
main { max-width: 720px; margin: 0 auto; padding: 48px 16px 64px; }
nav { display: flex; gap: 20px; font-size: 15px; margin-bottom: 32px; }
nav a { color: var(--secondary); text-decoration: none; }
nav a[aria-current="page"] { color: var(--text); font-weight: 600; }
h1 { font-size: 40px; line-height: 1.1; letter-spacing: -0.02em; margin: 0 0 8px; }
h2 { font-size: 24px; letter-spacing: -0.01em; margin: 0 0 12px; }
h3 { font-size: 18px; margin: 24px 0 6px; }
p, li { color: var(--text); }
.lead { color: var(--secondary); font-size: 19px; margin: 0 0 32px; }
.meta { color: var(--secondary); font-size: 14px; }
section.card { background: var(--card); border-radius: 18px; padding: 24px; margin: 0 0 20px; }
.app-title { display: flex; align-items: center; gap: 14px; margin-bottom: 12px; }
.app-title img { width: 56px; height: 56px; border-radius: 13px; }
.app-title h2 { margin: 0; }
a { color: var(--accent); }
ul { padding-left: 22px; }
hr { border: 0; border-top: 1px solid var(--line); margin: 24px 0; }
footer { color: var(--secondary); font-size: 14px; margin-top: 40px; }