:root{--ink:#1d1d1f;--muted:#6e6e73;--line:#e8e8ed;--soft:#f5f5f7;--blue:#0071e3;--purple:#7255c9;--orange:#a85917;--header:72px;--sidebar:240px;font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;color:var(--ink);font-size:16px;font-synthesis:none}*{box-sizing:border-box}body{margin:0;background:#fff}a{color:inherit;text-decoration:none}button,input{font:inherit}button,a,input{-webkit-tap-highlight-color:transparent}button{cursor:pointer}button:disabled{cursor:default}button{color:inherit}a,button,input{outline-offset:5px}a:focus-visible,button:focus-visible,input:focus-visible,summary:focus-visible{outline:3px solid #0071e3}button{border:0}::selection{background:#d5e9ff}.header{height:var(--header);display:flex;align-items:center;gap:36px;padding:0 34px;border-bottom:1px solid 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0}.section-head>span{color:var(--muted);font-size:12px;white-space:nowrap}.path-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:17px}.path-card{border:1px solid var(--line);border-radius:15px;padding:23px 22px;display:flex;flex-direction:column;min-height:216px;transition:box-shadow .2s,transform .2s}.path-card:hover{transform:translateY(-3px);box-shadow:0 8px 25px #1d1d1f09;border-color:#ceced5}.path-icon{width:36px;height:36px;border-radius:10px;display:grid;place-items:center;margin-bottom:18px}.path-icon svg{width:21px;height:21px}.blue{--accent:var(--blue);--tint:#edf5ff}.purple{--accent:var(--purple);--tint:#f2edff}.orange{--accent:var(--orange);--tint:#fdf3e9}.path-icon{background:var(--tint);color:var(--accent)}.path-card h3{margin:0 0 9px;font-size:19px;letter-spacing:-.4px}.path-card p{font-size:13px;line-height:1.8;color:var(--muted);margin:0 0 18px}.path-card 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@media(min-width:1500px){main{padding:60px 70px 85px}.hero h1{font-size:52px}.hero{gap:70px}.path-card{min-height:235px}.article-layout{gap:65px}}
@media(max-width:1200px){:root{--sidebar:215px}.header{padding:0 24px;gap:23px}.top-nav{gap:20px}.search-trigger .search-label{display:none}.search-trigger kbd{margin-left:0}.article-layout{grid-template-columns:minmax(0,1fr)}.toc{display:none}main{padding:38px 36px 64px}.hero{gap:25px;grid-template-columns:1.3fr 1fr}.hero h1{font-size:38px}.start-card{padding:20px}.path-card{padding:20px 17px}.path-card p{font-size:13px}.footer{padding:0 36px}}
@media(max-width:950px){.hero{grid-template-columns:1fr}.start-card{display:none}.path-grid{gap:10px}.path-card{padding:18px 14px}.path-card h3{font-size:17px}.path-card .card-meta{font-size:10px}.header .brand strong span{display:none}.quick-grid{grid-template-columns:1fr}.hero h1{font-size:43px}.footer{gap:15px;font-size:10px}.glossary-item{grid-template-columns:155px 1fr}}
@media(max-width:760px){:root{--header:60px;--sidebar:0px}.header{padding:0 18px;gap:14px}.brand strong{font-size:17px}.brand-mark{width:27px;height:27px;font-size:20px}.top-nav{gap:17px;font-size:12px}.top-nav a{line-height:60px}.search-trigger{background:transparent;border:0;padding:0;margin-left:auto}.search-trigger kbd{display:none}.mobile-menu{display:block;font-size:19px;width:30px}.sidebar{position:fixed;width:268px;left:0;top:var(--header);height:calc(100dvh - var(--header));z-index:29;transform:translateX(-100%);transition:transform .22s}.sidebar.open{transform:translateX(0)}.sidebar-shade{position:fixed;inset:var(--header) 0 0;background:#0004;z-index:28;backdrop-filter:blur(2px)}main{padding:32px 23px 50px;max-width:100%}.hero{padding-bottom:30px}.hero h1{font-size:38px;letter-spacing:-1px}.hero .intro{font-size:15px}.hero .eyebrow{font-size:10px}.hero-actions{gap:20px}.hero-note{font-size:11px}.path-grid{grid-template-columns:1fr}.path-card{min-height:0;position:relative;padding:21px 22px 21px 78px}.path-icon{position:absolute;left:22px;top:22px}.path-card h3{font-size:18px}.path-card p{margin-bottom:13px}.path-card .card-meta{font-size:11px;justify-content:flex-start;gap:18px}.section-head h2{font-size:21px}.section-head>span{font-size:11px}.editorial{padding:22px;display:block}.editorial a{display:inline-block;margin-top:16px}.footer{padding:22px 23px;height:auto;flex-wrap:wrap;gap:10px 20px}.footer a{margin-left:0}.footer span:first-child{display:none}.page-head h1{font-size:32px}.article-head h1{font-size:30px}.article-head .subtitle{font-size:16px}.article-meta{font-size:11px;gap:10px}.article-meta span+span:before{margin-right:10px}.article-body{font-size:16px}.article-body h2{font-size:22px}.step{padding-left:37px}.step p{font-size:15px}.screenshot button{padding:10px}.screenshot figcaption{font-size:10px}.course-row{gap:16px;align-items:flex-start}.course-row>.course-number{min-width:30px;font-size:23px}.course-row h3{font-size:17px}.course-row p{font-size:13px}.course-row .course-time{font-size:11px;padding-top:4px}.goal-box{padding:18px;font-size:13px;align-items:flex-start}.feature-grid{grid-template-columns:1fr}.glossary-item{grid-template-columns:1fr;gap:8px;padding:20px 0}.glossary-item h3{font-size:18px}.glossary-item p{margin-top:4px}.lesson-navigation{gap:10px}.lesson-navigation a{padding:14px 13px;font-size:13px}.complete-row{flex-wrap:wrap}.search-dialog{margin-top:8vh}.search-hint span{display:none}.search-top{padding:14px}.search-top input{font-size:14px}.prose{font-size:15px}.prose ul{padding-left:22px}.breadcrumb{font-size:11px;margin-bottom:24px}.code-block pre{font-size:12px;padding:17px}}
@media(max-width:380px){.top-nav{gap:11px;font-size:11px}.brand strong{font-size:15px}.brand-mark{display:none}.hero h1{font-size:33px}.header{gap:10px}.course-time{display:none}}
@media(prefers-reduced-motion:reduce){*,*:before,*:after{transition:none!important;scroll-behavior:auto!important}}
@media print{.header,.sidebar,.footer,.toc,.complete-row,.lesson-navigation,.related-links{display:none}.shell{display:block}main{padding:0;max-width:none}.article-layout{display:block}.screenshot{break-inside:avoid}.step{break-inside:avoid}body{font-size:12pt}}
.side-home svg{width:18px;height:18px;flex-shrink:0}