:root { --bg:#ffffff; --fg:#1c1c1e; --muted:#6b6b70; --accent:#3b5bdb; --card:#f4f5f8; --line:#e3e4ea; }
@media (prefers-color-scheme: dark) {
  :root { --bg:#111216; --fg:#f2f2f5; --muted:#9a9aa3; --accent:#8aa2ff; --card:#1b1c22; --line:#2a2b33; }
}
* { box-sizing: border-box; }
body { margin:0; background:var(--bg); color:var(--fg); font:17px/1.6 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif; }
main { max-width:720px; margin:0 auto; padding:32px 20px 64px; }
header.site { display:flex; flex-wrap:wrap; gap:8px 20px; align-items:baseline; justify-content:space-between; padding-bottom:16px; border-bottom:1px solid var(--line); margin-bottom:28px; }
header.site .brand { font-weight:700; font-size:1.25rem; color:var(--fg); text-decoration:none; }
header.site nav a { margin-right:16px; }
a { color:var(--accent); }
h1 { font-size:2rem; line-height:1.2; margin:0 0 4px; }
h2 { font-size:1.25rem; margin:32px 0 8px; }
p, li { margin:8px 0; }
.muted { color:var(--muted); font-size:.95rem; }
.card { background:var(--card); border:1px solid var(--line); border-radius:14px; padding:16px 20px; margin:16px 0; }
.card h2 { margin-top:0; }
footer { margin-top:48px; padding-top:16px; border-top:1px solid var(--line); color:var(--muted); font-size:.9rem; }
details { background:var(--card); border:1px solid var(--line); border-radius:12px; padding:12px 16px; margin:10px 0; }
summary { cursor:pointer; font-weight:600; }