@import url('https://fonts.googleapis.com/css2?family=DM+Sans:wght@400;500;600;700&family=Space+Grotesk:wght@400;500;600;700&display=swap');
:root{color-scheme:dark;--bg:#0b1014;--panel:#121a20;--panel2:#162128;--line:#26333b;--muted:#96a8b3;--text:#e9f0f2;--accent:#b5ed9c;--teal:#7ed9c4;--orange:#efb27e;--red:#ff9e9a;--radius:20px}*{box-sizing:border-box}body{margin:0;background:var(--bg);color:var(--text);font:15px/1.65 'DM Sans',system-ui,sans-serif}a{color:var(--teal);text-decoration:none}button,input,textarea,select{font:inherit}button,a,input,select,textarea{outline-offset:5px}button{cursor:pointer}button:disabled{cursor:default;opacity:.45}a:hover{color:#d6ffd5}button:hover{filter:brightness(1.12)}h1,h2,h3,h4,.brand,.big-number{font-family:'Space Grotesk',system-ui,sans-serif;line-height:1.2;letter-spacing:-.035em}h1{font-size:clamp(32px,4vw,52px);font-weight:500;margin:10px 0 18px}h2{font-size:25px;font-weight:500;margin:0}h3{font-size:20px;font-weight:500;margin:0 0 12px}p{margin:0 0 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nav{display:grid;gap:7px}.sidebar nav a{color:var(--muted);padding:11px 14px;border-radius:11px;display:flex;gap:12px;align-items:center;font-size:13px}.sidebar nav a span{width:18px;font-size:19px;color:inherit}.sidebar nav a.active{color:var(--accent);background:#24342a}.sidebar nav a small{margin-left:auto;color:inherit}.side-note{margin-top:auto;padding:28px 10px 0;font-size:9px;letter-spacing:.11em;color:var(--accent)}.side-note p{font-size:12px;letter-spacing:0;color:var(--muted);margin-top:14px}.side-note .tiny{letter-spacing:0;font-size:10px}.status-dot{display:inline-block;width:6px;height:6px;background:var(--accent);border-radius:50%;margin-right:5px}.shell{margin-left:252px;min-width:0}.topbar{height:90px;border-bottom:1px solid var(--line);display:flex;align-items:center;gap:20px;padding:0 48px}.breadcrumb{font-size:10px;letter-spacing:.13em;color:#738692;white-space:nowrap}.breadcrumb 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a{font-size:12px}.btn{border:1px solid var(--line);color:var(--text);background:var(--panel2);border-radius:10px;padding:10px 15px;display:inline-flex;gap:8px;align-items:center;justify-content:center;font-size:12px;font-weight:600;min-height:42px}.btn.primary{background:var(--accent);color:#142219;border-color:var(--accent)}.btn.ghost{background:transparent}.btn.small{padding:6px 10px;min-height:32px;font-size:11px}.hero{display:grid;grid-template-columns:1.15fr 1fr;gap:38px;align-items:center;padding:34px;border:1px solid #33443c;border-radius:24px;background:radial-gradient(ellipse at 100% 20%,#263a2a 0,transparent 68%),#141f1b;margin:26px 0}.hero h2{font-size:clamp(28px,3vw,40px);margin:12px 0 16px}.hero p{max-width:440px;font-size:13px;color:#a9bcb0}.hero .eyebrow{color:#a1c4a6}.hero-visual{min-width:0;border-radius:16px;border:1px solid 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@media(min-width:1700px){main{padding-left:65px;padding-right:65px}}@media(max-width:1150px){.sidebar{width:215px;padding:30px 16px}.shell{margin-left:215px}main{padding:34px 28px 50px}.topbar{padding:0 28px}.grid{grid-template-columns:repeat(2,minmax(0,1fr))}.hero{gap:22px;padding:26px}.detail-layout{grid-template-columns:minmax(0,1fr) 240px;gap:20px}.stat{padding:16px}.big-number{font-size:26px}}@media(max-width:850px){.sidebar{display:none}.shell{margin-left:0}.topbar{height:68px;padding:0 22px}.mobile-nav{position:fixed;bottom:0;left:0;right:0;display:flex;justify-content:space-around;padding:9px 0 max(9px,env(safe-area-inset-bottom));background:#101b21f5;border-top:1px solid #33443a;z-index:10;backdrop-filter:blur(15px)}.mobile-nav a{display:grid;text-align:center;font-size:19px;line-height:1.3;min-width:65px;color:var(--muted)}.mobile-nav span{font-size:9px}footer{padding-bottom:100px}.detail-layout{grid-template-columns:1fr}.note-panel{position:static;order:2}.note-panel textarea{height:90px}.hero h2{font-size:32px}#toast{bottom:88px}.hero{grid-template-columns:1fr 1fr}}@media(max-width:600px){body{font-size:14px}.topbar{gap:10px;padding:0 18px}.breadcrumb{font-size:8px;max-width:92px;white-space:normal}#global-search{width:auto;flex:1}#global-query{font-size:10px}kbd{display:none}.avatar{width:29px;height:29px}main{padding:28px 18px 40px}h1{font-size:36px;line-height:1.1}.intro{font-size:13px}.hero{grid-template-columns:1fr;padding:23px;gap:25px;margin-top:22px}.hero h2{font-size:33px}.hero-visual{padding:18px}.hero .array{margin:23px 0 17px}.stats{grid-template-columns:repeat(2,minmax(0,1fr));gap:10px}.stat{padding:17px}.big-number{font-size:28px}.grid,.grid.two{grid-template-columns:1fr}.section{margin-top:30px}.section-title h2{font-size:22px}.card{padding:22px}.question{padding:16px;gap:10px}.question h3{font-size:16px}.question .q-index{font-size:10px}.question .arrow{padding:3px}.question .meta{font-size:9px}.filters{padding:14px;gap:8px}.filters .field{width:100%;flex-basis:100%}.filters select{flex:1;min-width:calc(50% - 8px);width:0;font-size:11px}.detail-head h1{font-size:33px}.lab{padding:16px}.lab-state{grid-template-columns:1fr}.lab .tile{min-width:28px;font-size:12px}.lab-inputs{gap:7px}.lab-message{font-size:12px}.lab-controls .btn{padding:7px 10px;font-size:10px}.lab-controls .speed{max-width:80px;min-width:70px}.approach summary{padding:16px}.approach .inside{padding:0 16px 16px}.approach h3{font-size:17px}.prose pre,pre.code{font-size:11px;padding:14px}.prose h2{font-size:22px}.resource{display:block}.resource small{display:block;margin-top:5px}.reading-row{display:block}.reading-row small{display:block;margin-top:3px}.tabs{gap:5px}.tabs .btn{padding:8px 10px;font-size:10px}.path{gap:6px}.path a{font-size:10px}.notice{padding:15px;font-size:11px}footer{padding-left:18px;padding-right:18px;gap:10px}footer a{margin-left:0;width:100%}.completion .btn{margin-top:10px}}@media(prefers-reduced-motion:reduce){*{transition:none!important;scroll-behavior:auto!important}.tile{transform:none!important}}
.runtime-toolbar{display:flex;gap:12px;align-items:end;flex-wrap:wrap;margin:20px 0}.runtime-toolbar label{font-size:11px;color:var(--muted)}.runtime-toolbar select{display:block;margin-top:5px}.workspace>p{max-width:760px}.editor-wrap{position:relative;height:340px;border:1px solid var(--line);border-radius:13px;background:#0a1117;overflow:hidden;margin:7px 0 17px}.editor-wrap .editor,.editor-wrap .editor-mirror{position:absolute;inset:0;width:100%;height:100%;margin:0;padding:18px;border:0;border-radius:0;white-space:pre;overflow:auto;tab-size:4;font:12px/1.7 ui-monospace,SFMono-Regular,Consolas,monospace;letter-spacing:0}.editor-wrap .editor{background:transparent;color:transparent;caret-color:#e9f0f2;z-index:2;resize:none;-webkit-text-fill-color:transparent}.editor-wrap .editor::selection{background:#526e7266}.editor-wrap .editor-mirror{pointer-events:none;z-index:1;scrollbar-width:none}.editor-wrap .editor-mirror::-webkit-scrollbar{display:none}.editor-wrap .editor-mirror code{font:inherit!important;padding:0!important;background:transparent!important;white-space:pre}.runtime-input{display:block;width:100%;font:12px/1.7 ui-monospace,monospace;margin:7px 0;tab-size:4}.test-panel{border:1px solid var(--line);border-radius:12px;padding:15px;margin-top:18px}.test-panel summary{cursor:pointer;font-size:13px}.test-panel p{margin:12px 0 0}.runtime-metrics{display:flex;gap:10px;flex-wrap:wrap;margin:15px 0}.metric{padding:10px 14px;background:#18271e;border:1px solid #35523c;border-radius:10px;min-width:96px}.metric small{display:block;font-size:9px}.metric strong{font:14px 'Space Grotesk',sans-serif;color:var(--accent)}.test-result{border:1px solid var(--line);padding:15px;border-radius:11px;margin:10px 0}.test-result summary{cursor:pointer;font-size:12px}.test-result.passed{border-color:#426e49}.test-result.failed{border-color:#7d4747}.prose pre code.hljs{background:transparent;padding:0;font:inherit}.prose pre{color:#c9d1d9}.runtime-input[hidden],[hidden]{display:none!important}
@media(max-width:600px){.editor-wrap{height:300px}.editor-wrap .editor,.editor-wrap .editor-mirror{font-size:12px;padding:14px}.runtime-toolbar{gap:8px}.runtime-toolbar label{flex:1;min-width:120px}.runtime-toolbar select{width:100%}.metric{min-width:72px;padding:8px 11px}}