:root { --fg: #1c2430; --muted: #5b6676; --bg: #fbfbf9; --line: #e3e5e8; --accent: #1f5fa8; }
@media (prefers-color-scheme: dark) {
  :root { --fg: #e6e9ee; --muted: #9aa4b2; --bg: #14181d; --line: #2a313b; --accent: #7fb2ee; }
}
* { box-sizing: border-box; }
body { margin: 0; background: var(--bg); color: var(--fg); font: 17px/1.6 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif; }
header, main, footer { max-width: 720px; margin: 0 auto; padding: 0 16px; }
header { display: flex; flex-wrap: wrap; gap: 12px; align-items: baseline; justify-content: space-between; padding-top: 28px; padding-bottom: 12px; border-bottom: 1px solid var(--line); }
.brand { font-weight: 700; color: var(--fg); text-decoration: none; }
nav a { margin-left: 14px; }
a { color: var(--accent); }
h1 { font-size: 1.9rem; line-height: 1.2; margin: 36px 0 8px; }
h2 { font-size: 1.2rem; margin: 36px 0 8px; }
h3 { font-size: 1.05rem; margin: 20px 0 4px; }
.lead { color: var(--muted); font-size: 1.1rem; }
article p { margin-top: 0; }
footer { color: var(--muted); font-size: 0.9rem; border-top: 1px solid var(--line); margin-top: 48px; padding-top: 12px; padding-bottom: 32px; }