:root{--bg:#F6FAFC;--white:#fff;--pale:#EAF6FA;--pale2:#EDF4F8;--aqua:#25C8D1;--sky:#25B6E8;--blue:#1787DB;--navy:#174B78;--ink:#183A56;--body:#31485D;--muted:#687D8E;--line:#DCE9F0;--footer:#123653;--radius:18px;--wrap:1180px}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:30px}body{margin:0;color:var(--body);background:var(--bg);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:var(--blue)}a:focus-visible,button:focus-visible,summary:focus-visible{outline:3px solid var(--sky);outline-offset:3px}button{font:inherit;cursor:pointer}.wrap{max-width:var(--wrap);padding:0 28px;margin:0 auto}.skip-link{position:absolute;top:-90px;left:12px;z-index:200;background:#fff;padding:10px}.skip-link:focus{top:10px}.site-header{background:#fff;border-bottom:1px solid 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