:root{--bg:#F6F8F8;--paper:#fff;--soft:#EAF0F2;--ink:#193946;--body:#374D58;--muted:#647981;--border:#D9E3E6;--header:#122E3B;--panel:#1A4050;--accent:#168E96;--link:#226D9D}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:100px}body{margin:0;background:var(--bg);color:var(--body);font:16px/1.82 Arial,"PingFang SC","Microsoft YaHei",sans-serif;overflow-wrap:break-word}a{color:var(--link);text-underline-offset:3px}a:hover{color:#11616e}a:focus-visible,button:focus-visible,summary:focus-visible{outline:3px solid #23aab3;outline-offset:3px}h1,h2,h3{color:var(--ink);line-height:1.33;letter-spacing:.01em}h1{font-size:clamp(34px,3vw,42px);margin:0 0 20px}h2{font-size:27px;margin:0 0 20px}h3{font-size:20px;margin:0 0 12px}p{margin:0 0 18px}ul,ol{padding-left:1.5em;margin:0 0 22px}.container{width:min(1220px,calc(100% - 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