:root{--paper:#f4f2ed;--ink:#17343c;--muted:#527076;--teal:#176d70;--line:#ccd8d2;--soft:#e7eeea;--white:#fff;--accent:#a95735}*{box-sizing:border-box}body{margin:0;background:var(--paper);color:var(--ink);font:16px/1.65 -apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif}a{color:var(--teal);text-underline-offset:4px}button,input,select{font:inherit}button,a,input,select,summary{-webkit-tap-highlight-color:transparent}button{cursor:pointer}button:focus-visible,a:focus-visible,summary:focus-visible,input:focus-visible,select:focus-visible{outline:3px solid #ae5d35;outline-offset:4px}[hidden]{display:none!important}.skip{position:absolute;top:-90px;background:white;padding:12px;z-index:5}.skip:focus{top:10px}.site-header{display:flex;justify-content:space-between;align-items:center;gap:25px;padding:22px max(24px,calc((100vw - 1250px)/2));border-bottom:1px solid 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.language-control{display:flex;align-items:center;gap:8px;font-size:13px;white-space:nowrap}.language-control select{font:inherit;color:inherit;background:var(--paper,#fff);border:1px solid #a9bcb5;border-radius:5px;padding:6px 8px;max-width:130px}html[lang="zh-CN"] body{font-family:-apple-system,BlinkMacSystemFont,"PingFang SC","Microsoft YaHei",sans-serif}html[lang="zh-CN"] h1,html[lang="zh-CN"] h2{font-family:inherit;line-height:1.4}html[lang="zh-CN"] .hero h1{font-size:clamp(32px,4vw,54px)}html[lang="zh-CN"] .course-card h3{line-height:1.5}@media(max-width:700px){.site-header nav{flex-wrap:wrap}.language-control{margin-left:auto}.language-control span{font-size:12px}}
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