:root { --bg:#f5f5f7; --card:#fff; --text:#1d1d1f; --muted:#6e6e73; --accent:#5856d6; --line:#e5e5ea; }
@media (prefers-color-scheme: dark) { :root { --bg:#000; --card:#1c1c1e; --text:#f5f5f7; --muted:#a1a1a6; --accent:#7d7aff; --line:#38383a; } }
* { box-sizing: border-box; }
body { margin:0; background:var(--bg); color:var(--text); font:17px/1.6 -apple-system, BlinkMacSystemFont, "PingFang SC", "Helvetica Neue", sans-serif; }
main { max-width: 720px; margin: 0 auto; padding: 40px 20px 80px; }
header { display:flex; align-items:center; gap:16px; margin-bottom:28px; }
header img { width:72px; height:72px; border-radius:16px; box-shadow:0 6px 20px rgba(0,0,0,.15); }
header h1 { margin:0; font-size:28px; }
header p { margin:2px 0 0; color:var(--muted); }
nav { display:flex; gap:10px; flex-wrap:wrap; margin-bottom:24px; }
nav a, .lang button { color:var(--accent); text-decoration:none; font-weight:600; padding:6px 14px; border-radius:999px; background:var(--card); border:1px solid var(--line); font-size:15px; cursor:pointer; font-family:inherit; }
.lang { position:fixed; top:14px; right:14px; display:flex; gap:6px; }
section { background:var(--card); border-radius:20px; padding:22px 24px; margin-bottom:16px; }
h2 { font-size:20px; margin:0 0 10px; }
h3 { font-size:17px; margin:18px 0 6px; }
p, li { color:var(--text); }
.muted { color:var(--muted); font-size:15px; }
a { color:var(--accent); }
body [lang] { display:none; }
html[data-lang="zh"] [lang="zh"], html[data-lang="en"] [lang="en"] { display:revert; }