:root{color-scheme:light;--text:#172537;--muted:#576579;--accent:#1266cf;--line:#dce3ed;--paper:#fff;--bg:#f4f7fb}
*{box-sizing:border-box}body{margin:0;background:var(--bg);color:var(--text);font:16px/1.65 system-ui,-apple-system,Segoe UI,Roboto,Arial,sans-serif}
header{border-bottom:1px solid var(--line);background:#fff}header .inner{max-width:910px;margin:auto;padding:20px 24px;display:flex;align-items:center;justify-content:space-between;gap:18px}header strong{font-size:22px;letter-spacing:.08em}nav{display:flex;flex-wrap:wrap;gap:16px}a{color:var(--accent)}nav a{font-size:14px;text-decoration:none}main{max-width:910px;margin:32px auto;padding:35px 42px;background:var(--paper);border:1px solid var(--line);border-radius:18px;box-shadow:0 8px 26px #1525350a}h1{font-size:clamp(27px,4vw,36px);line-height:1.25;margin:0 0 14px}h2{font-size:19px;margin:30px 0 8px}h3{font-size:16px;margin:18px 0 6px}p,li{color:#283849}li{margin:6px 0}ul,ol{padding-left:22px}.lede{font-size:17px;color:var(--muted)}.note{padding:13px 18px;border-left:4px solid #176acc;background:#f0f6ff;border-radius:8px}footer{max-width:910px;margin:12px auto 35px;padding:10px 24px;color:var(--muted);font-size:13px}.meta{font-size:13px;color:var(--muted)}@media(max-width:600px){header .inner{display:block}nav{margin-top:10px}main{margin:16px 10px;padding:22px 20px}}