:root{--bg:#F4F7FA;--white:#fff;--soft:#EAF1F6;--mint:#E9F8F8;--nav:#102E46;--deep:#163C57;--teal:#13B8C5;--blue:#237BD3;--heading:#18364B;--text:#344C60;--muted:#64798A;--line:#DCE6ED}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:var(--bg);font-family:Arial,'PingFang SC','Microsoft YaHei',sans-serif;color:var(--text);font-size:16px;line-height:1.8;overflow-wrap:break-word}a{color:#146cae;text-decoration:none}a:hover{text-decoration:underline}a:focus-visible,button:focus-visible,summary:focus-visible{outline:3px solid #13B8C5;outline-offset:3px}button{font:inherit;cursor:pointer}img{max-width:100%;height:auto}h1,h2,h3{color:var(--heading);line-height:1.4;letter-spacing:-.018em}h1{font-size:clamp(2rem,3vw,2.65rem);margin:0 0 18px}h2{font-size:clamp(1.45rem,2.1vw,1.75rem);margin:0 0 18px}h3{font-size:1.2rem;margin:0 0 12px}p{margin:0 0 18px}.container{width:min(1200px,calc(100% - 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