:root{color-scheme:light;--bg:#f5f7f5;--card:#fff;--ink:#23343c;--line:#d7e1e2;--accent:#126886}html[data-theme=dark]{color-scheme:dark;--bg:#15242b;--card:#1b2d35;--ink:#e7eff0;--line:#36505b;--accent:#87c8dc}*{box-sizing:border-box}body{margin:0;background:var(--bg);color:var(--ink);font:16px/1.85 system-ui,sans-serif}header,main,footer{max-width:1000px;margin:auto;padding:24px}header{display:flex;justify-content:space-between;gap:16px;align-items:center}a{color:var(--accent);text-underline-offset:4px}h1{font-size:clamp(28px,5vw,44px);line-height:1.3}h2{line-height:1.5}h3{margin-bottom:8px;font-size:17px}nav{display:grid;grid-template-columns:1fr 1fr;gap:12px;margin:28px 0}nav a{padding:12px;background:var(--card);border:1px solid var(--line);border-radius:4px}article{scroll-margin-top:24px;background:var(--card);border:1px solid var(--line);border-radius:5px;padding:28px;margin:24px 0}li{margin:10px 0}.notice,.eyebrow{color:var(--accent)}blockquote{margin:0;border-left:3px solid var(--accent);padding:12px 18px;background:var(--bg)}button{font:inherit;color:var(--ink);background:var(--card);border:1px solid var(--line);border-radius:8px;padding:7px 12px;cursor:pointer}.feedback{display:flex;gap:10px;flex-wrap:wrap;align-items:center;border-top:1px solid var(--line);padding-top:20px;margin-top:24px}footer{font-size:13px}button:focus-visible,a:focus-visible{outline:3px solid var(--accent);outline-offset:3px}@media(max-width:600px){header,main,footer{padding:16px}header span{display:none}nav{grid-template-columns:1fr}article{padding:20px}ol{padding-left:24px}}

/* Atlas companion typography: existing article text, anchors and controls are preserved. */
body{font-family:"Microsoft YaHei UI","PingFang SC","Microsoft YaHei","Segoe UI",sans-serif}h1{font-weight:650;letter-spacing:-1.2px}header{border-bottom:1px solid var(--line)}nav a{background:transparent;border-width:0 0 1px;padding:14px 0;border-radius:0}article{box-shadow:none}a:focus-visible,button:focus-visible{outline:2px solid var(--accent);outline-offset:4px}@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important}}