:root{--bg:#F4F7FA;--paper:#fff;--soft:#EAF1F6;--aqua:#E9F8F8;--nav:#102E46;--deep:#163C57;--cyan:#13B8C5;--blue:#237BD3;--heading:#18364B;--body:#344C60;--muted:#64798A;--line:#DCE6ED;--footer:#0B2539;--footertext:#DCECF5}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:28px}body{margin:0;min-width:0;background:var(--bg);color:var(--body);font:16px/1.8 Arial,'PingFang SC','Microsoft YaHei',sans-serif}body.menu-open{overflow:hidden}a{color:#176CA9;text-underline-offset:3px}a:hover{color:#087E94}button{font:inherit;cursor:pointer}img{max-width:100%;height:auto}h1,h2,h3{color:var(--heading);line-height:1.38;margin:0 0 .65em}h1{font-size:clamp(32px,3.1vw,36px)}h2{font-size:clamp(23px,2.4vw,27px)}h3{font-size:20px}p{margin:0 0 1.15em}ul,ol{padding-left:1.35em}li{margin:.4em 0}strong{color:var(--heading)}.container{width:min(100% - 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