:root{color-scheme:light dark;--ink:#172033;--muted:#64748b;--bg:#f5f7fa;--card:#fff;--brand:#2563eb}
@media (prefers-color-scheme:dark){:root{--ink:#e5e9f0;--muted:#9aa8bc;--bg:#0d1424;--card:#151e30;--brand:#60a5fa}}
body{margin:0;background:var(--bg);color:var(--ink);font:16px/1.6 "Segoe UI",system-ui,sans-serif}
main{max-width:720px;margin:0 auto;padding:40px 20px}
header{display:flex;align-items:center;gap:14px}h1{margin:0;font-size:28px}h2{font-size:18px;margin-top:28px}
.lead{font-size:18px}.meta,footer{color:var(--muted);font-size:14px}footer{margin-top:40px}
a{color:var(--brand)}.button{display:inline-block;background:#2563eb;color:#fff;padding:10px 18px;border-radius:8px;text-decoration:none;font-weight:600}
code{font-size:14px}