:root{color-scheme:light;--bg:#f7f8f5;--surface:#fff;--text:#213d3a;--muted:#697d73;--border:#e0e7e1;--soft:#edf3ee;--green:#123e3b;--mint:#86d2b0;--gold:#f0c36a;--code:#142d2a;--code-text:#e1eee5}*{box-sizing:border-box}body{margin:0;background:var(--bg);color:var(--text);font:14px/1.8 -apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei",sans-serif}a{color:inherit;text-decoration:none}button,input,select{font:inherit}button,summary{cursor:pointer}button:focus-visible,a:focus-visible,input:focus-visible,select:focus-visible,summary:focus-visible{outline:3px solid var(--mint);outline-offset:3px}[hidden]{display:none!important}.topbar{height:88px;display:flex;align-items:center;justify-content:space-between;padding:0 44px;border-bottom:1px solid var(--border);background:var(--surface)}.brand{display:flex;align-items:center;gap:13px;font-size:22px;line-height:1.3}.brand small{display:block;font-size:10px;letter-spacing:2px;color:var(--muted);margin-top:5px}.brand-icon{position:relative;display:grid;place-content:center;width:46px;height:46px;border-radius:14px;background:var(--green);color:var(--gold);font:bold 23px monospace}.brand-icon span{position:absolute;right:4px;top:2px;color:var(--mint);font-size:17px}.header-actions{display:flex;gap:24px;align-items:center}.header-actions a{font-size:12px;color:var(--muted)}#theme{width:35px;height:35px;border-radius:50%;border:1px solid var(--border);color:var(--text);background:var(--surface);font-size:22px;line-height:1}.layout{display:grid;grid-template-columns:240px minmax(0,1fr);max-width:1500px;margin:auto}.sidebar{position:sticky;top:0;align-self:start;height:100vh;overflow-y:auto;border-right:1px solid var(--border);padding:38px 24px}.sidebar-heading{display:flex;justify-content:space-between;font-size:9px;letter-spacing:1.5px;color:var(--muted);margin-bottom:22px}.sidebar-heading span{letter-spacing:0}.topic-link{display:flex;align-items:center;gap:12px;padding:17px 13px;border-radius:9px;margin:7px 0;font-size:12px}.topic-link>span:first-child{font:12px monospace;color:var(--muted)}.topic-link b{font-size:15px;margin-left:auto;font-weight:400;color:var(--muted)}.topic-link:hover{background:var(--soft)}.topic-link.active{background:var(--green);color:white}.topic-link.active>span:first-child{color:var(--mint)}.topic-link.active b{color:var(--gold)}.sidebar-note{font-size:10px;color:var(--muted);margin-top:32px;padding-top:22px;border-top:1px solid var(--border)}.sidebar-note p{margin:4px 0 0 13px}.live-dot{display:inline-block;width:6px;height:6px;background:var(--mint);border-radius:50%;margin-right:6px}.progress{margin-top:29px;color:var(--muted)}.progress>div{display:flex;justify-content:space-between;font-size:10px}.progress progress{width:100%;height:5px;accent-color:var(--green)}.progress small{font-size:9px}.sibling{display:block;font-size:10px;color:var(--muted);margin-top:32px}main{padding:28px 48px;min-width:0}.breadcrumb{display:flex;gap:13px;font-size:10px;color:var(--muted);margin-bottom:24px}.hero{display:flex;justify-content:space-between;position:relative;overflow:hidden;border-radius:17px;background:var(--green);color:white;padding:33px 38px;min-height:300px}.hero-copy{z-index:1;max-width:580px}.eyebrow{font-size:9px;letter-spacing:1.5px;color:var(--muted);font-weight:600}.hero .eyebrow{color:#b1d1c5}h1{font-size:43px;letter-spacing:-1.5px;line-height:1.4;margin:16px 0 12px;font-weight:650}h1 span{color:var(--gold)}.hero h2{font-size:15px;font-weight:500;margin:0 0 6px}.hero p{font-size:12px;color:#c0d8cd;margin:0;max-width:430px}.hero-tags{display:flex;gap:8px;margin-top:20px}.hero-tags span{font-size:9px;color:#c9e3d5;border:1px solid #ffffff26;padding:3px 10px;border-radius:5px}.hero-art{position:relative;width:210px;min-width:170px;height:235px;align-self:center;margin-left:16px}.orbit{position:absolute;inset:14px;border:1px solid #a0d6b92e;border-radius:50%;transform:rotate(-25deg)}.database{position:absolute;top:46px;left:40px;width:124px;height:125px;transform:rotate(-8deg)}.database span{position:absolute;left:0;width:124px;height:52px;border:1px solid #f0c36a99;background:linear-gradient(90deg,#31524a,#1a4740);border-radius:50%/28%}.database span:before{content:"";position:absolute;top:0;left:0;right:0;height:27px;border-radius:50%;background:#f0c36a1c;border-bottom:1px solid #f0c36a70}.database span:nth-child(1){top:68px}.database span:nth-child(2){top:34px}.database span:nth-child(3){top:0}.art-tag{position:absolute;bottom:3px;right:0;background:#204d45;border:1px solid #84c9a347;border-radius:8px;padding:10px 16px;font:10px/1.8 monospace;color:#bce8cd;transform:rotate(4deg)}.hero-art i{position:absolute;right:8px;top:5px;font:35px serif;color:var(--gold)}.dataset{margin-top:22px}.dataset>details{background:var(--surface);border:1px solid var(--border);border-radius:10px;overflow:hidden}.dataset summary{display:flex;align-items:center;justify-content:space-between;padding:17px 22px;list-style:none}.dataset h2{font-size:15px;margin:3px 0 0}.dataset h2 span{font-size:10px;font-weight:400;color:var(--muted);margin-left:10px}.dataset summary>b{font-size:22px;font-weight:400;color:var(--muted)}.dataset-body{padding:0 22px 20px}.dataset-body>p{font-size:12px;color:var(--muted)}.dataset-body .code-panel{border-radius:8px}.download{display:inline-block;margin-top:12px;font-size:11px;text-decoration:underline}.section-heading{margin-top:36px;margin-bottom:18px}.section-heading h2{font-size:23px;letter-spacing:-.5px;margin:4px 0 0}.section-heading h2>span{font-size:12px;color:var(--muted);font-weight:400;margin-left:10px}.section-heading>p{font-size:12px;color:var(--muted);margin:7px 0}.lesson-heading{display:flex;justify-content:space-between;align-items:center;gap:20px}.search{display:flex;align-items:center;gap:8px;background:var(--surface);border:1px solid var(--border);border-radius:7px;padding:7px 12px;color:var(--muted);font-size:23px}.search input{width:170px;min-width:0;font-size:11px;color:var(--text);background:none;border:0}.controls{display:flex;justify-content:space-between;gap:16px;font-size:10px;color:var(--muted);margin-bottom:20px}.controls select{margin-left:7px;border:1px solid var(--border);border-radius:6px;padding:4px 8px;background:var(--surface);color:var(--text);font-size:10px}.controls>span{font-size:9px}.lesson{display:grid;grid-template-columns:minmax(0,.95fr) minmax(0,1fr);border:1px solid var(--border);border-radius:12px;background:var(--surface);overflow:hidden;margin:15px 0}.lesson-copy{padding:24px}.lesson-meta{display:flex;justify-content:space-between;gap:12px;color:var(--muted);font:10px monospace}.lesson-meta>span:last-child{font-size:9px;background:var(--soft);padding:2px 7px;border-radius:4px}.lesson h3{font-size:19px;line-height:1.5;margin:15px 0 10px}.lesson-copy>p{font-size:12px;color:var(--muted);margin:0}.lesson-copy .before{border-top:1px solid var(--border);padding-top:12px;margin-top:15px;font-size:11px}.before strong{display:block;font-size:10px;color:var(--text)}.caution{border-left:3px solid var(--gold);padding-left:12px;margin:17px 0}.caution strong{font-size:10px}.caution p{font-size:11px;color:var(--muted);margin:5px 0}.source-link{font-size:10px;text-decoration:underline}.review-date{font-size:9px;margin-left:12px;color:var(--muted)}.lesson-example{min-width:0;border-left:1px solid var(--border)}.code-panel{background:var(--code);color:var(--code-text);overflow:hidden}.code-heading{display:flex;justify-content:space-between;padding:10px 18px;border-bottom:1px solid #ffffff0d;color:#b5cfc1;font:9px monospace}.copy{font-size:9px;padding:3px 0;background:none;border:0;color:#c4dbc9}pre{overflow:auto;font:11px/1.9 Consolas,monospace;padding:18px;margin:0}pre code{font:inherit}.result{padding:15px 18px}.result h4,.exercise h4{font-size:10px;margin:0 0 9px}.result>p{font-size:11px;color:var(--muted);margin:0}.table-scroll{overflow-x:auto}table{width:100%;border-collapse:collapse;font:11px/1.8 monospace;text-align:left}th{color:var(--muted);font-weight:500;font-size:10px;background:var(--soft)}th,td{padding:7px 9px;border-bottom:1px solid var(--border);white-space:nowrap}.exercise{padding:18px;border-top:1px solid var(--border);background:var(--soft)}.exercise>p,.exercise details>p{font-size:11px;color:var(--muted);margin:0 0 10px;overflow-wrap:anywhere}.exercise details{background:var(--surface);border:1px solid var(--border);border-radius:6px;margin-top:13px}.exercise summary{display:flex;justify-content:space-between;padding:9px 12px;font-size:10px;list-style:none}.exercise details>p{padding:0 12px 10px;margin:0}.complete{display:flex;gap:7px;align-items:center;margin-top:14px;font-size:10px;color:var(--muted);cursor:pointer}.complete input{accent-color:var(--green);margin:0}.source-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:13px}.source-card{background:var(--surface);border:1px solid var(--border);border-radius:10px;padding:20px;min-width:0}.source-card h3{font-size:13px;margin:0 0 9px}.source-card p{font-size:11px;color:var(--muted);margin:0}.source-card ul{list-style:none;padding:0;margin:13px 0;font-size:10px}.source-card li{padding:6px 0;border-bottom:1px solid var(--border);overflow-wrap:anywhere}.updated-badge{display:block;font-size:9px;font-weight:400;color:var(--muted);margin-top:4px}footer{margin-top:35px;border-top:1px solid var(--border);padding-top:22px;display:flex;justify-content:space-between;gap:20px;color:var(--muted);font-size:9px}footer p{margin:4px 0}footer>div:last-child{text-align:right}#empty{padding:25px;background:var(--surface);border-radius:8px}#toast{position:fixed;bottom:28px;left:50%;transform:translateX(-50%);padding:10px 20px;background:var(--green);color:white;border-radius:8px;opacity:0;pointer-events:none;font-size:12px}#toast.visible{opacity:1}.sr-only,.skip{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0,0,0,0)}.skip:focus{clip:auto;width:auto;height:auto;padding:10px;background:var(--surface);top:8px;left:8px;z-index:10}:root[data-theme=dark]{color-scheme:dark;--bg:#111e1c;--surface:#182a26;--text:#dcece2;--muted:#9ab5a8;--border:#2b4238;--soft:#20362d;--green:#1b4b40;--code:#102721}
@media(max-width:1100px){.layout{grid-template-columns:210px minmax(0,1fr)}.sidebar{padding:30px 18px}main{padding:28px}.hero{padding:30px}h1{font-size:37px}.hero-art{transform:scale(.85);width:160px;min-width:140px;margin-left:0}.source-grid{grid-template-columns:1fr}.source-card ul{display:flex;flex-wrap:wrap;gap:8px}.source-card li{border:0;padding:2px 0}}@media(max-width:800px){.topbar{height:74px;padding:0 22px}.layout{display:block}.sidebar{position:sticky;top:0;z-index:3;height:auto;overflow:visible;background:var(--bg);border-right:0;border-bottom:1px solid var(--border);padding:14px 22px 10px}.sidebar-heading{margin-bottom:8px}.sidebar nav{display:flex;gap:8px;overflow-x:auto;padding-bottom:3px}.topic-link{flex:none;margin:0;padding:10px 12px;gap:8px}.topic-link b{display:none}.sidebar-note,.progress,.sibling{display:none}.hero-art{width:190px;min-width:160px}.controls>span{max-width:50%}}@media(max-width:560px){.topbar{padding:0 17px}.brand{font-size:18px}.brand-icon{width:39px;height:39px;font-size:20px}.brand small{font-size:8px}.header-actions{gap:13px}.header-actions a{font-size:10px}.sidebar{padding:13px 17px 9px}main{padding:19px 17px}.breadcrumb{font-size:9px;margin-bottom:18px;gap:10px}.hero{padding:25px 23px;min-height:295px}h1{font-size:34px}.hero .eyebrow{font-size:8px;letter-spacing:1px}.hero-art{position:absolute;right:-57px;top:30px;opacity:.15;transform:scale(1.2)}.hero-copy{position:relative}.hero p{font-size:11px}.hero h2{font-size:14px}.dataset summary{padding:15px}.dataset h2{font-size:13px}.dataset h2 span{display:block;margin:3px 0 0;font-size:9px}.dataset .eyebrow{font-size:8px;letter-spacing:.8px}.dataset-body{padding:0 15px 15px}.lesson-heading{align-items:start;flex-direction:column;gap:12px}.section-heading h2{font-size:21px}.search{width:100%}.search input{width:100%;font-size:12px}.controls{gap:8px}.controls>span{font-size:8px}.lesson{grid-template-columns:1fr}.lesson-copy{padding:22px}.lesson h3{font-size:18px}.lesson-example{border-left:0;border-top:1px solid var(--border)}.source-card{padding:18px}footer{flex-direction:column;gap:15px}footer>div:last-child{text-align:left}#toast{width:max-content;max-width:90vw}}