:root{--bg:#f6fafc;--surface:#fff;--pale:#eaf6fa;--pale2:#edf4f8;--teal:#25c8d1;--sky:#25b6e8;--blue:#1787db;--navy:#174b78;--heading:#183a56;--text:#31485d;--muted:#687d8e;--line:#dce9f0;--footer:#123653;--radius:16px}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:30px}body{margin:0;background:var(--bg);color:var(--text);font:16px/1.8 Arial,"PingFang SC","Microsoft YaHei",sans-serif;overflow-x:hidden}a{color:#126cb5;text-underline-offset:4px}a:hover{color:#07538c}a:focus-visible,button:focus-visible,summary:focus-visible{outline:3px solid #079cc0;outline-offset:4px}img{max-width:100%;height:auto}h1,h2,h3{line-height:1.38;color:var(--heading);letter-spacing:-.025em}h1{font-size:clamp(27px,3.5vw,42px);margin:12px 0 20px}h2{font-size:clamp(20px,2.5vw,27px);margin:0 0 15px}h3{font-size:clamp(17px,2vw,21px);margin:0 0 12px}p{margin:0 0 16px}ul,ol{padding-left:1.4em}li{margin:0 0 9px}small{font-size:.8em}.shell{width:min(100% - 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@media(max-height:480px) and (max-width:640px){.mobile-bottom-nav{position:static}.site-footer{padding-bottom:0}.back-top{bottom:16px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*:before,*:after{animation-duration:.01ms!important;transition-duration:.01ms!important}}