:root{--bg:#F4F7FA;--paper:#fff;--muted:#EAF1F6;--aqua:#E9F8F8;--nav:#102E46;--nav2:#163C57;--teal:#13B8C5;--blue:#237BD3;--title:#18364B;--text:#344C60;--sub:#64798A;--line:#DCE6ED;--max:1200px}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:24px}body{margin:0;background:var(--bg);color:var(--text);font-family:Arial,'PingFang SC','Microsoft YaHei',sans-serif;font-size:16px;line-height:1.8}body.drawer-open{overflow:hidden}img{max-width:100%;height:auto}a{color:#16659D;text-decoration:none}a:hover{text-decoration:underline}button{font:inherit}button,a,summary{ -webkit-tap-highlight-color:transparent}a:focus-visible,button:focus-visible,summary:focus-visible{outline:3px solid var(--teal);outline-offset:3px}h1,h2,h3{line-height:1.4;color:var(--title);margin:0 0 .65em;font-weight:750}h1{font-size:clamp(32px,3.15vw,44px)}h2{font-size:clamp(23px,2.35vw,28px)}h3{font-size:20px}p{margin:0 0 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