:root{--bg:#F4F7FA;--paper:#fff;--soft:#EAF1F6;--mint:#E9F8F8;--nav:#102E46;--dark:#163C57;--cyan:#13B8C5;--blue:#237BD3;--title:#18364B;--text:#344C60;--muted:#64798A;--line:#DCE6ED;--footer:#0B2539;--gutter:28px}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:24px}body{margin:0;background:var(--bg);color:var(--text);font-family:Arial,'PingFang SC','Microsoft YaHei',sans-serif;font-size:16px;line-height:1.8;overflow-wrap:break-word}a{color:#1266a7;text-underline-offset:3px}a:hover{color:#075284}a:focus-visible,button:focus-visible,summary:focus-visible{outline:3px solid var(--cyan);outline-offset:3px}h1,h2,h3{color:var(--title);line-height:1.38;margin:0 0 .7em;font-weight:750}h1{font-size:35px}h2{font-size:27px}h3{font-size:20px}p{margin:0 0 1.1em}strong{color:var(--title)}img{max-width:100%}.container{width:min(100% - 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