:root{--ink:#16222d;--blue:#4d7490;--accent:#dc2730;--soft:#eaf0f4;--line:#d6e0e6;--muted:#63717c;--shell:1420px}
*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:78px}body{margin:0;min-width:320px;font-family:Arial,"Microsoft YaHei","PingFang SC",sans-serif;color:var(--ink);line-height:1.76;background:#fff}img{display:block;max-width:100%}a{text-decoration:none;color:inherit}.shell{width:min(calc(100% - 56px),var(--shell));margin:auto}
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