:root{--bg:#F6FAFC;--surface:#fff;--wash:#EAF6FA;--pale:#EDF4F8;--cyan:#25C8D1;--sky:#25B6E8;--blue:#1787DB;--navy:#174B78;--title:#183A56;--text:#31485D;--muted:#687D8E;--line:#DCE9F0;--footer:#123653}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:26px}body{margin:0;background:var(--bg);color:var(--text);font:16px/1.8 Arial,'PingFang SC','Microsoft YaHei',sans-serif;overflow-x:hidden}body.drawer-open{overflow:hidden}a{color:var(--navy);text-decoration-thickness:1px;text-underline-offset:4px}a:hover{color:#0876ac}button,a,summary{ -webkit-tap-highlight-color:transparent } :focus-visible{outline:3px solid var(--sky);outline-offset:3px}img{max-width:100%;height:auto}p{margin:0 0 1.15em}h1,h2,h3{color:var(--title);line-height:1.38;letter-spacing:-.02em}h1{font-size:clamp(27px,3.4vw,42px);margin:0 0 22px}h2{font-size:clamp(21px,2.45vw,27px);margin:0 0 22px}h3{font-size:19px;margin:0 0 10px}ul,ol{padding-left:1.4em}li{margin:0 0 8px}.wrap{width:min(100% - 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