:root{--bg:#F4F7FA;--white:#fff;--pale:#EAF1F6;--mint:#E9F8F8;--navy:#102E46;--deep:#163C57;--teal:#13B8C5;--blue:#237BD3;--ink:#18364B;--body:#344C60;--muted:#64798A;--line:#DCE6ED;--foot:#0B2539}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:25px}body{margin:0;background:var(--bg);color:var(--body);font:16px/1.82 Arial,"PingFang SC","Microsoft YaHei",sans-serif}a{color:#146aa5;text-decoration-thickness:1px;text-underline-offset:4px}a:hover{color:#0d4a73}a:focus-visible,button:focus-visible,summary:focus-visible{outline:3px solid var(--teal);outline-offset:4px}img{max-width:100%}h1,h2,h3{color:var(--ink);line-height:1.36;margin:0 0 .75em}h1{font-size:clamp(32px,3vw,42px);letter-spacing:-.025em}h2{font-size:27px}h3{font-size:20px}p{margin:0 0 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