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:root{--ink:#203732;--muted:#53665e;--paper:#f7f8f4;--line:#dce4dc;--teal:#146b55;--soft:#edf3e9;--sidebar:264px;--measure:62ch;--top:64px}*{box-sizing:border-box}html{scroll-behavior:auto;scroll-padding-top:88px}body{margin:0;background:var(--paper);color:var(--ink);font:16px/1.7 "Segoe UI","Microsoft YaHei",sans-serif}button,input,select{font:inherit}button,a,summary{touch-action:manipulation}button{cursor:pointer;border:1px solid var(--line);border-radius:7px;background:white;color:var(--ink);padding:8px 12px;line-height:1.45}button:hover{background:var(--soft);border-color:#8ea694}button:disabled{opacity:.45;cursor:default}a{color:var(--teal);text-underline-offset:4px}button:focus-visible,a:focus-visible,summary:focus-visible,input:focus-visible{outline:3px solid #bd873a;outline-offset:3px}h1,h2,h3,h4,p{margin-top:0}h1,h2,h3,h4{line-height:1.35}p{margin-bottom:18px}h1{font-size:27px;margin:4px 0 8px;letter-spacing:-.5px}h2{font-size:31px;margin:12px 0 18px;letter-spacing:-.6px}h3{font-size:22px;margin:0 0 16px}h4{font-size:18px;margin:0 0 14px}.skip{position:fixed;top:-100px;left:15px;z-index:100;background:white;padding:10px}.skip:focus{top:12px}[hidden]{display:none!important}
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/* Keep the learning content close to the top of each page. */
.hero{padding-bottom:12px}.hero .eyebrow{display:none}.hero h1{font-size:22px;margin:0 0 4px}.hero p{font-size:12px}.lessonHeader{padding:2px 0 14px;margin-bottom:14px}.lessonHeader h2{font-size:29px;margin:8px 0 12px}.lessonHeader p{font-size:12px;margin-bottom:11px}.sectionNav{margin:12px 0 15px}.sectionNav .expandAll{font-size:10px;padding:5px 8px;background:transparent;border-style:dashed}.contentSection{padding-top:21px}

.labGroup[data-lab="normal"]>.lab:last-child,.labGroup[data-lab="lln"]>.lab:first-child{display:none}

/* Reader restores its own semantic position when language or content changes. */
html,body,.workspace,main,#view{overflow-anchor:none}


html{scroll-padding-top:0}.lesson,[data-reading-anchor]{scroll-margin-top:88px}
@media(max-width:600px){.lesson,[data-reading-anchor]{scroll-margin-top:76px}}