:root{--bg:#F6FAFC;--white:#fff;--pale:#EAF6FA;--pale2:#EDF4F8;--brand:#1787DB;--cyan:#25C8D1;--navy:#174B78;--heading:#183A56;--body:#31485D;--muted:#687D8E;--border:#DCE9F0;--footer:#123653}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:24px}body{margin:0;background:var(--bg);color:var(--body);font:16px/1.8 Arial,'PingFang SC','Microsoft YaHei',sans-serif;overflow-x:hidden}a{color:var(--navy);text-underline-offset:3px}a:hover{color:#0977B4}a:focus-visible,button:focus-visible,summary:focus-visible{outline:3px solid #25B6E8;outline-offset:3px}h1,h2,h3{color:var(--heading);line-height:1.38;margin:0 0 .7em}h1{font-size:clamp(2rem,3.2vw,2.625rem);letter-spacing:-.025em}h2{font-size:clamp(1.45rem,2.25vw,1.7rem)}h3{font-size:1.24rem}p{margin:0 0 1.15em}ul,ol{padding-left:1.5em;margin:0 0 1.3em}li+li{margin-top:.5em}.wrap{width:min(1180px,calc(100% - 56px));margin-inline:auto}.site-header{background:#fff;border-bottom:1px solid 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