:root{--ink:#1d2433;--muted:#5b6475;--line:#e3e6ec;--bg:#ffffff;--soft:#f5f6f8;--accent:#3a4ea8}
*{box-sizing:border-box}
html,body{margin:0;padding:0}
body{font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;color:var(--ink);background:var(--bg);line-height:1.6;font-size:16px}
a{color:var(--accent)}
.wrap{max-width:880px;margin:0 auto;padding:0 20px}
header{border-bottom:1px solid var(--line)}
header .wrap{display:flex;justify-content:space-between;align-items:center;height:64px}
.logo{font-weight:700;font-size:18px;color:var(--ink);text-decoration:none;letter-spacing:.2px}
nav a{color:var(--muted);text-decoration:none;margin-left:20px;font-size:15px}
nav a:hover{color:var(--ink)}
.hero{padding:72px 0 48px}
.hero h1{font-size:36px;line-height:1.2;margin:0 0 16px}
.hero p{font-size:18px;color:var(--muted);margin:0;max-width:620px}
section{padding:40px 0;border-top:1px solid var(--line)}
section h2{font-size:22px;margin:0 0 16px}
.grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:16px}
.card{border:1px solid var(--line);border-radius:12px;padding:20px;background:var(--bg)}
.card h3{margin:0 0 8px;font-size:17px}
.card p{margin:0;color:var(--muted);font-size:15px}
dl{display:grid;grid-template-columns:200px 1fr;gap:10px 16px;margin:0}
dt{color:var(--muted)}
dd{margin:0}
footer{background:var(--soft);border-top:1px solid var(--line);margin-top:40px;padding:32px 0;font-size:14px;color:var(--muted)}
footer p{margin:4px 0}
.doc{padding:48px 0}
.doc h1{font-size:30px;margin:0 0 8px}
.doc h2{font-size:19px;margin:28px 0 8px}
.doc p,.doc li{color:#333a48}
@media (max-width:560px){.hero h1{font-size:28px}dl{grid-template-columns:1fr}dt{margin-top:8px}nav a{margin-left:14px}}