:root{--bg:#f4f7fa;--paper:#fff;--soft:#eaf1f6;--mint:#e9f8f8;--navy:#102e46;--deep:#163c57;--cyan:#13b8c5;--blue:#237bd3;--title:#18364b;--text:#344c60;--muted:#64798a;--line:#dce6ed}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:24px}body{margin:0;background:var(--bg);color:var(--text);font:16px/1.8 Arial,'PingFang SC','Microsoft YaHei',sans-serif}body.drawer-open{overflow:hidden}a{color:#1466a6;text-underline-offset:3px}a:hover{color:#0797a6}a:focus-visible,button:focus-visible,summary:focus-visible{outline:3px solid var(--cyan);outline-offset:3px}img{max-width:100%;height:auto}figure{margin:0}.wrap{width:min(1200px,calc(100% - 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