*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;color:#202020;background:#fff;font:14px/1.7 ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif}button,input,textarea{font:inherit}a{color:inherit;text-decoration:none}button,a,input,textarea,summary{outline-offset:4px}button:focus-visible,a:focus-visible,input:focus-visible,textarea:focus-visible,summary:focus-visible{outline:2px solid #555}button{cursor:pointer;background:white;color:#242424;border:1px solid #dedede;border-radius:8px;padding:8px 13px;font-size:12px}button:hover,a.soft:hover{background:#f3f3f3}.skip{position:fixed;top:-80px;left:280px;background:#111;color:white;padding:10px;z-index:100}.skip:focus{top:10px}.sidebar{position:fixed;inset:0 auto 0 0;width:246px;background:#f8f8f8;border-right:1px solid #ebebeb;display:flex;flex-direction:column;padding:25px 17px;z-index:30}.logo{font-weight:750;font-size:18px;letter-spacing:-.7px;display:flex;gap:9px;align-items:center;margin:0 10px 27px}.logo svg{width:23px;height:23px}.nav-label{font-size:9px;color:#888;letter-spacing:1.3px;text-transform:uppercase;margin:24px 12px 7px;font-weight:650}.nav-link{display:flex;align-items:center;gap:11px;border-radius:7px;padding:9px 12px;font-size:12px;margin:3px 0;color:#5e5e5e}.nav-link:hover{background:#eee}.nav-link.active{background:#e9e9e9;color:#111;font-weight:650}.nav-icon{width:21px;display:inline-grid;place-items:center;font-size:13px;font-weight:650;color:#555}.nav-link small{margin-left:auto;font-size:9px;color:#888}.sidebar-footer{margin-top:auto;padding:20px 12px 0;border-top:1px solid #e6e6e6;font-size:10px;color:#929292;line-height:1.8}.sidebar-footer b{display:block;color:#666;font-weight:500}.shell{margin-left:246px;min-height:100vh}.topbar{height:72px;display:flex;justify-content:space-between;align-items:center;border-bottom:1px solid #eee;padding:0 38px;gap:20px;color:#888;font-size:11px}.crumb{display:flex;gap:10px}.crumb strong{font-weight:500;color:#333}.search{display:flex;align-items:center;gap:10px;max-width:320px;width:100%;background:#f8f8f8;border:1px solid #e8e8e8;border-radius:9px;padding:8px 12px}.search input{border:0;background:none;outline:none;width:100%;font-size:11px;color:#444}.search kbd{border:1px solid #ddd;border-radius:4px;padding:0 5px;font-size:10px;color:#999}#menu-toggle{display:none}.content{max-width:1060px;padding:45px 55px 25px;margin:auto}.welcome{text-align:center;max-width:660px;margin:26px auto 45px}.eyebrow{font-size:10px;letter-spacing:1.7px;color:#888;font-weight:600;text-transform:uppercase}.welcome h1{font-size:47px;line-height:1.18;letter-spacing:-2px;font-weight:650;margin:18px 0}.welcome p{font-size:14px;color:#808080;max-width:460px;margin:0 auto 24px}.actions{display:flex;gap:10px;justify-content:center;flex-wrap:wrap}.button{display:inline-flex;align-items:center;justify-content:center;gap:9px;padding:10px 17px;border-radius:8px;border:1px solid #dedede;font-size:11px;font-weight:600}.button.primary{color:white;background:#202020;border-color:#202020}.button.primary:hover{background:#404040}.section-heading{display:flex;justify-content:space-between;align-items:center;margin:35px 0 16px}.section-heading h2{font-size:15px;font-weight:650;margin:0}.section-heading span{font-size:10px;color:#999}.tracks{display:grid;grid-template-columns:repeat(3,1fr);gap:15px}.track{border:1px solid #e4e4e4;border-radius:12px;padding:23px;display:flex;flex-direction:column;min-height:235px;transition:box-shadow .15s,border-color .15s}.track:hover{border-color:#aaa;box-shadow:0 5px 20px #00000005}.symbol{display:inline-flex;align-items:center;justify-content:center;width:34px;height:34px;border:1px solid #ddd;border-radius:8px;background:#fafafa;font-size:11px;font-weight:700;margin-bottom:17px}.track h3{font-size:17px;margin:0 0 7px;font-weight:650;letter-spacing:-.3px}.track p{font-size:11px;color:#888;line-height:1.8;margin:0 0 20px;flex:1}.track-footer{display:flex;justify-content:space-between;align-items:center;font-size:10px;color:#888}.track-footer b{color:#333;font-weight:500}.demo-banner{margin-top:25px;border:1px solid #e4e4e4;background:#fafafa;border-radius:12px;padding:23px;display:flex;gap:22px;align-items:center}.demo-banner .demo-copy{flex:1}.demo-banner h3{font-size:14px;margin:0 0 5px}.demo-banner p{font-size:11px;color:#888;margin:0}.badge{border:1px solid #e1e1e1;background:#f7f7f7;border-radius:5px;font-size:9px;padding:3px 7px;white-space:nowrap;color:#777}.roadmap-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:13px}.roadmap-card{padding:17px;border:1px dashed #ddd;border-radius:9px;color:#888}.roadmap-card strong{font-size:12px;font-weight:500;display:block;color:#666;margin-bottom:6px}.roadmap-card p{font-size:10px;margin:6px 0 0}.bottom{display:flex;justify-content:space-between;border-top:1px solid #efefef;margin-top:40px;padding:22px 0;font-size:9px;color:#aaa;gap:20px}.page-heading h1{font-size:34px;font-weight:650;letter-spacing:-1px;margin:10px 0}.page-heading p{color:#888;font-size:13px;max-width:600px}.course-meta{display:flex;gap:18px;color:#888;font-size:10px;margin:17px 0}.lesson-list{margin:30px 0;border-top:1px solid #e5e5e5}.lesson-row{display:flex;gap:18px;padding:21px 8px;border-bottom:1px solid #e8e8e8;align-items:center}.lesson-row:hover{background:#fafafa}.lesson-number{font-size:12px;color:#999;min-width:24px}.lesson-row h3{font-size:14px;font-weight:550;margin:0 0 3px}.lesson-row p{font-size:11px;color:#999;margin:0}.lesson-row .row-main{flex:1}.lesson-row small{color:#999;font-size:10px}.lesson-layout{display:grid;grid-template-columns:185px minmax(0,1fr);gap:34px}.lesson-nav{align-self:start;position:sticky;top:25px}.lesson-nav a{display:block;padding:8px 10px;border-radius:7px;font-size:11px;color:#888;margin:3px 0}.lesson-nav a.active{background:#f1f1f1;color:#222}.lesson-nav .nav-label{margin:0 10px 15px}.article{min-width:0}.article h1{font-size:33px;font-weight:650;line-height:1.25;letter-spacing:-1px;margin:12px 0 15px}.article h2{font-size:17px;font-weight:650;margin:32px 0 10px}.article p{font-size:13px;color:#737373;line-height:1.95}.article .lead{font-size:14px;color:#888}.codebox{border:1px solid #e1e1e1;border-radius:10px;overflow:hidden;margin-top:18px}.codebar{display:flex;justify-content:space-between;align-items:center;background:#f7f7f7;border-bottom:1px solid #e5e5e5;padding:8px 13px;font-size:10px;color:#888}.codebar button{border:0;background:none;padding:3px 8px;font-size:10px}.codebox pre{margin:0;padding:20px;overflow:auto;background:#fcfcfc;font:11px/1.85 ui-monospace,SFMono-Regular,Consolas,monospace;color:#343434;tab-size:2}.callout{border-left:2px solid #bbb;padding:10px 17px;background:#fafafa;border-radius:0 7px 7px 0;font-size:12px;color:#777;margin:22px 0}.callout strong{display:block;color:#444;font-size:11px;margin-bottom:4px}details{border:1px solid #e4e4e4;border-radius:9px;padding:15px 17px;margin:16px 0}summary{cursor:pointer;font-size:12px;font-weight:500}textarea{width:100%;border:1px solid #ddd;border-radius:8px;min-height:100px;padding:12px;font-size:12px;resize:vertical;color:#444;margin-top:8px}label{font-size:12px;color:#666}.article-tools{display:flex;gap:8px;align-items:center;margin:20px 0;flex-wrap:wrap}.article-tools span{font-size:10px;color:#999}.pager{display:flex;gap:15px;justify-content:space-between;margin-top:35px}.pager a{border:1px solid #e1e1e1;border-radius:9px;padding:12px;max-width:48%;font-size:11px;color:#555}.search-result{display:block;padding:20px 0;border-bottom:1px solid #eee}.search-result h3{font-size:15px;margin:0 0 5px}.search-result p{font-size:12px;color:#888;margin:0}.empty{padding:35px 0;text-align:center;color:#999}.reference{font-size:11px!important}.reference a{text-decoration:underline;text-underline-offset:3px}.progress-track{height:3px;background:#eee;border-radius:4px;overflow:hidden}.progress-track span{display:block;height:100%;background:#555}.resource-card{border:1px solid #ddd;border-radius:12px;padding:27px;margin-top:20px}.resource-card h2{font-size:21px;margin:0 0 10px}.resource-card p{font-size:13px;color:#888;max-width:600px}.resource-card ul{font-size:12px;color:#888;padding-left:20px}.resource-links{display:flex;gap:12px;flex-wrap:wrap;margin-top:20px}#site-toast{position:fixed;bottom:22px;left:calc(50% + 123px);transform:translateX(-50%);padding:11px 20px;background:#242424;color:white;border-radius:9px;font-size:12px;z-index:100}#site-toast:empty{display:none}.backdrop{display:none}@media(max-width:1100px){.content{padding:32px}.lesson-layout{grid-template-columns:150px minmax(0,1fr);gap:22px}.track{padding:18px}.welcome h1{font-size:39px}}@media(max-width:850px){.tracks{grid-template-columns:1fr}.track{min-height:0}.track p{margin-bottom:13px}.track-footer{margin-top:10px}.roadmap-grid{grid-template-columns:1fr}.demo-banner{align-items:start;flex-wrap:wrap}.demo-banner .demo-copy{min-width:200px}.lesson-layout{display:block}.lesson-nav{position:static;display:flex;overflow:auto;gap:5px;margin-bottom:25px}.lesson-nav a{white-space:nowrap;font-size:10px;flex-shrink:0}.lesson-nav .nav-label{display:none}}@media(max-width:650px){.sidebar{transform:translateX(-100%);transition:transform .2s}.sidebar.open{transform:translateX(0)}.shell{margin-left:0}.topbar{height:65px;padding:0 17px;gap:12px}.crumb{display:none}#menu-toggle{display:block;border:0;padding:7px;font-size:18px;min-height:44px;min-width:44px}.search{max-width:100%}.search input{font-size:12px;min-height:24px}.search kbd{display:none}.content{padding:25px 20px}.welcome{margin:30px auto}.welcome h1{font-size:37px}.welcome p{font-size:13px}.tracks{gap:12px}.track{padding:21px}.button,button{min-height:44px}.codebar button{min-height:36px}.backdrop.visible{display:block;position:fixed;inset:0;background:#0004;z-index:29}.section-heading span{font-size:9px}.article h1{font-size:29px}.lesson-row{gap:10px}.lesson-row small{min-width:34px}.demo-banner{padding:20px;gap:15px}.demo-banner .button{width:100%}.bottom{flex-wrap:wrap;gap:7px}.skip{left:15px}#site-toast{left:50%;max-width:90vw}.codebox pre{font-size:11px;padding:15px}.page-heading h1{font-size:29px}.course-meta{flex-wrap:wrap;gap:9px}.resource-links .button{width:100%}}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}.sidebar,.track{transition:none}}

.visit-counters{position:fixed;right:18px;bottom:18px;display:flex;gap:8px;z-index:20;pointer-events:none}.count-box{width:96px;height:96px;background:#000;color:#fff;display:flex;flex-direction:column;align-items:center;justify-content:center;border:1px solid #333;box-shadow:0 3px 12px #0002}.count-box strong{font-size:23px;line-height:1.3;font-weight:650;max-width:100%;overflow-wrap:anywhere}.count-box span{font-size:10px;margin-top:5px}.content{padding-bottom:140px}#site-toast{bottom:125px}@media(max-width:650px){.visit-counters{right:12px;bottom:12px;gap:6px}.count-box{width:76px;height:76px}.count-box strong{font-size:19px}.count-box span{font-size:9px}.content{padding-bottom:110px}#site-toast{bottom:100px}}
