:root{color-scheme:light;--bg: #f5f6fa;--surface: #ffffff;--surface-2: #f0f2f7;--border: #e2e5ee;--text: #1c2333;--text-dim: #6b7280;--accent: #4f46e5;--accent-soft: #eef0ff;--accent-2: #0ea5e9;--ok: #16a34a;--warn: #d92b2b;--cell: #eef2ff;--cell-border: #6366f1;--cell-changed: #fde68a;--cell-changed-border: #f59e0b;--cell-cursor: #dcfce7;--cell-cursor-border: #16a34a;--node: #e0f2fe;--node-border: #0284c7;--edge: #94a3b8;--shadow: 0 6px 24px rgba(20, 24, 45, .08);--radius: 14px;--mono: "SFMono-Regular", "JetBrains Mono", Consolas, "Liberation Mono", monospace;--sans: "Inter", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif}[data-theme=dark]{color-scheme:dark;--bg: #0e1017;--surface: #171a24;--surface-2: #1e222f;--border: #2a2f3d;--text: #e7eaf3;--text-dim: #9aa3b8;--accent: #818cf8;--accent-soft: #232742;--accent-2: #38bdf8;--ok: #4ade80;--warn: #f87171;--cell: #232a44;--cell-border: #6366f1;--cell-changed: #4d3f16;--cell-changed-border: #f59e0b;--cell-cursor: #14361f;--cell-cursor-border: #4ade80;--node: #10344b;--node-border: #38bdf8;--edge: #4b5568;--shadow: 0 6px 24px rgba(0, 0, 0, .4)}*{box-sizing:border-box}html,body,#root{height:100%;margin:0}body{background:var(--bg);color:var(--text);font-family:var(--sans);font-size:14px}.app{display:flex;flex-direction:column;height:100%}.app-header{display:flex;align-items:center;justify-content:space-between;padding:12px 20px;background:linear-gradient(120deg,var(--surface),var(--surface-2));border-bottom:1px solid var(--border)}.brand{display:flex;align-items:center;gap:12px}.brand-mark{font-size:28px;color:var(--accent);filter:drop-shadow(0 2px 6px rgba(79,70,229,.3))}.brand-name{margin:0;font-size:19px;font-weight:700;letter-spacing:-.02em}.brand-tag{margin:0;font-size:12px;color:var(--text-dim)}.header-actions{display:flex;align-items:center;gap:10px}.segmented{display:flex;background:var(--surface-2);border:1px solid var(--border);border-radius:10px;padding:3px}.segment{border:none;background:transparent;color:var(--text-dim);padding:6px 14px;border-radius:8px;cursor:pointer;font-weight:600;font-size:13px}.segment.active{background:var(--accent);color:#fff;box-shadow:0 2px 8px #4f46e559}.btn{border:1px solid var(--border);background:var(--surface);color:var(--text);padding:7px 12px;border-radius:9px;cursor:pointer;font-size:14px;font-family:var(--sans);transition:transform .05s ease,background .15s ease}.btn:hover:not(:disabled){background:var(--surface-2)}.btn:active:not(:disabled){transform:translateY(1px)}.btn:disabled{opacity:.45;cursor:not-allowed}.btn-primary{background:var(--accent);border-color:var(--accent);color:#fff;font-weight:600}.btn-primary:hover:not(:disabled){background:var(--accent);filter:brightness(1.08)}.btn-ghost{background:transparent}.workspace{flex:1;display:grid;grid-template-columns:minmax(300px,.85fr) minmax(380px,1.05fr) minmax(340px,1fr);gap:16px;padding:16px;min-height:0}.pane{display:flex;flex-direction:column;min-height:0;background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);box-shadow:var(--shadow);overflow:hidden}.toolbar{display:flex;gap:10px;align-items:flex-end;padding:12px;border-bottom:1px solid var(--border);flex-wrap:wrap}.field{display:flex;flex-direction:column;gap:4px}.field-grow{flex:1;min-width:140px}.field label{font-size:11px;text-transform:uppercase;letter-spacing:.04em;color:var(--text-dim);font-weight:600}.text-input,.example-picker,.library-picker{background:var(--surface-2);border:1px solid var(--border);border-radius:8px;padding:7px 10px;color:var(--text);font-family:var(--mono);font-size:13px;width:100%}.example-picker,.library-picker{font-family:var(--sans);font-weight:600;cursor:pointer;align-self:stretch;color-scheme:light dark}.text-input:focus,.example-picker:focus,.library-picker:focus{outline:2px solid var(--accent);outline-offset:-1px}.editor-wrap{flex:1;min-height:0;overflow:hidden}.editor-host{height:100%}.editor-host .cm-editor{height:100%;font-family:var(--mono);font-size:13.5px}.editor-host .cm-active-step{background:#4f46e529;box-shadow:inset 3px 0 0 var(--accent)}.controls{display:flex;align-items:center;gap:12px;padding:10px 12px;border-top:1px solid var(--border);background:var(--surface-2);flex-wrap:wrap}.controls-group{display:flex;gap:4px}.controls-group .btn{padding:6px 10px;min-width:38px}.scrubber{flex:1;min-width:100px;accent-color:var(--accent)}.step-counter{font-family:var(--mono);font-size:12px;color:var(--text-dim);min-width:62px;text-align:center}.speed{display:flex;align-items:center;gap:6px;font-size:12px;color:var(--text-dim)}.speed input{accent-color:var(--accent-2);width:90px}.example-meta{padding:12px 16px;border-bottom:1px solid var(--border)}.badge{display:inline-block;background:var(--accent-soft);color:var(--accent);font-weight:700;font-size:11px;padding:3px 9px;border-radius:999px;margin-right:10px}.complexity{font-size:12px;color:var(--text-dim)}.complexity strong{color:var(--text);font-family:var(--mono)}.example-desc{margin:8px 0 0;color:var(--text-dim);line-height:1.5}.viz-scroll{flex:1;min-height:0;overflow:auto;padding:16px}.viz-canvas{display:flex;flex-direction:column;gap:18px}.viz-empty{color:var(--text-dim);text-align:center;padding:40px 0;font-style:italic}.viz-block{display:flex;flex-direction:column;gap:6px}.viz-block-label{font-family:var(--mono);font-size:12px;color:var(--text-dim);font-weight:600}.viz-block-body{overflow-x:auto}.viz-cell{fill:var(--cell);stroke:var(--cell-border);stroke-width:1.5px}.viz-cell-changed{fill:var(--cell-changed);stroke:var(--cell-changed-border)}.viz-cell-cursor{fill:var(--cell-cursor);stroke:var(--cell-cursor-border);stroke-width:2.5px}.viz-cursor-label{fill:var(--cell-cursor-border);font-family:var(--mono);font-size:11px;font-weight:700}.viz-cell-text{fill:var(--text);font-family:var(--mono);font-size:14px;font-weight:600}.viz-index-text{fill:var(--text-dim);font-family:var(--mono);font-size:10px}.viz-edge{stroke:var(--edge);stroke-width:1.6px}.viz-arrow-head{fill:var(--edge)}.viz-node{fill:var(--node);stroke:var(--node-border);stroke-width:1.6px}.viz-node-text{fill:var(--text);font-family:var(--mono);font-size:12px;font-weight:600}.viz-kv{border-collapse:collapse;font-family:var(--mono);font-size:12.5px}.viz-kv 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16px;max-height:30%;overflow:auto;display:flex;flex-direction:column;gap:10px}.output-label{font-size:11px;text-transform:uppercase;letter-spacing:.04em;color:var(--text-dim);font-weight:700;margin-bottom:3px}.output-label-error{color:var(--warn)}.output-console,.output-return,.output-error{margin:0;font-family:var(--mono);font-size:12.5px;white-space:pre-wrap;word-break:break-word}.output-return{color:var(--ok)}.output-error{color:var(--warn)}.output-note{font-family:var(--mono);font-size:12px;color:var(--text-dim)}.output-status{color:var(--accent);font-size:13px}.browser-backdrop{position:fixed;inset:0;background:#0a0c148c;display:grid;place-items:start center;padding:8vh 16px 16px;z-index:50;backdrop-filter:blur(2px)}.browser{width:min(760px,100%);max-height:80vh;display:flex;flex-direction:column;background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);box-shadow:0 24px 60px #00000059;overflow:hidden}.browser-head{display:flex;gap:8px;align-items:center;padding:12px;border-bottom:1px solid var(--border)}.browser-search{flex:1;background:var(--surface-2);border:1px solid var(--border);border-radius:9px;padding:9px 12px;color:var(--text);font-family:var(--sans);font-size:14px}.browser-search:focus{outline:2px solid var(--accent);outline-offset:-1px}.browser-close{font-size:15px;line-height:1}.browser-body{overflow-y:auto;padding:6px 0}.browser-group-label{margin:12px 14px 6px;font-size:11px;text-transform:uppercase;letter-spacing:.06em;color:var(--text-dim)}.browser-row{display:flex;align-items:center;justify-content:space-between;gap:12px;width:100%;text-align:left;padding:10px 14px;background:transparent;border:none;border-left:3px solid transparent;cursor:pointer;color:var(--text);font-family:var(--sans)}.browser-row:hover{background:var(--surface-2)}.browser-row.current{border-left-color:var(--accent);background:var(--accent-soft)}.browser-row-main{display:flex;flex-direction:column;gap:3px;min-width:0}.browser-row-title{font-weight:600;font-size:14px}.solved-tick{color:var(--ok);margin-right:6px}.browser-row-desc{font-size:12px;color:var(--text-dim);overflow:hidden;text-overflow:ellipsis;display:-webkit-box;-webkit-line-clamp:1;-webkit-box-orient:vertical}.browser-row-meta{display:flex;align-items:center;gap:6px;flex-shrink:0}.browser-empty{padding:28px 14px;text-align:center;color:var(--text-dim)}.browser-foot{padding:9px 14px;border-top:1px solid var(--border);font-size:12px;color:var(--text-dim);background:var(--surface-2)}.toolbar-stacked{flex-direction:column;align-items:stretch;gap:8px}.switcher{display:flex;gap:6px;width:100%}.switcher .library-picker{flex:1;min-width:0}.switcher-step{padding:7px 10px;min-width:34px;font-size:13px}.browse-btn{width:100%;justify-content:center;font-weight:600}.item-scroll{flex:1;min-height:0;overflow-y:auto;padding:16px}.item-heading{display:flex;align-items:center;justify-content:space-between;gap:12px}.item-title{margin:0;font-size:19px;letter-spacing:-.01em}.difficulty{font-size:11px;font-weight:700;padding:3px 10px;border-radius:999px;white-space:nowrap}.difficulty-easy{background:#16a34a24;color:var(--ok)}.difficulty-medium{background:#d9770629;color:#d97706}.difficulty-hard{background:#d92b2b24;color:var(--warn)}.topic-row{display:flex;flex-wrap:wrap;gap:6px;margin:10px 0 4px}.item-text{line-height:1.65;color:var(--text);margin:10px 0}.complexity-line strong{font-family:var(--mono)}.item-subhead{font-size:12px;text-transform:uppercase;letter-spacing:.06em;color:var(--text-dim);margin:20px 0 8px}.example-card{background:var(--surface-2);border-left:3px solid var(--accent);border-radius:8px;padding:10px 12px;margin-bottom:10px}.example-row{display:flex;gap:10px;margin-bottom:4px;font-size:13px}.example-key{color:var(--text-dim);font-weight:600;min-width:54px}.example-row code,.constraint-list code{font-family:var(--mono);font-size:12.5px;word-break:break-word}.example-explanation{margin:6px 0 0;font-size:12.5px;color:var(--text-dim);line-height:1.5}.constraint-list{margin:0;padding-left:20px;color:var(--text-dim);line-height:1.9}.item-hint{margin:18px 0 0;padding-top:12px;border-top:1px solid var(--border);font-size:12.5px;color:var(--text-dim);line-height:1.5}.toggle{display:flex;align-items:center;gap:6px;font-size:12px;color:var(--text-dim);white-space:nowrap;cursor:pointer}.results-panel{border-top:1px solid var(--border);background:var(--surface-2);padding:12px 14px;max-height:34%;overflow-y:auto}.results-summary{font-weight:700;font-size:14px;margin-bottom:10px}.results-summary.passed{color:var(--ok)}.results-summary.failed{color:var(--warn)}.results-hint,.results-status{color:var(--text-dim);font-size:13px}.results-status{color:var(--accent)}.case-dots{display:flex;flex-wrap:wrap;gap:5px;margin-bottom:10px}.case-dot{width:22px;height:22px;border-radius:6px;display:grid;place-items:center;font-size:12px;font-weight:700}.case-dot.pass{background:#16a34a29;color:var(--ok)}.case-dot.fail{background:#d92b2b24;color:var(--warn)}.failure-detail{border-top:1px solid var(--border);padding-top:10px}.failure-title{font-size:11px;text-transform:uppercase;letter-spacing:.05em;color:var(--text-dim);font-weight:700;margin-bottom:6px}.failure-table{border-collapse:collapse;width:100%;font-size:12.5px}.failure-table td{padding:3px 0;vertical-align:top}.failure-table td:first-child{color:var(--text-dim);width:74px;font-weight:600}.failure-table code{font-family:var(--mono);word-break:break-word}.error-text{color:var(--warn)}.results-error{margin:8px 0 0;font-family:var(--mono);font-size:12px;color:var(--warn);white-space:pre-wrap}.viz-status-bar{display:flex;justify-content:flex-end;padding:8px 16px 0;min-height:28px}.live-chip{font-size:11px;font-weight:700;padding:2px 9px;border-radius:999px;text-transform:uppercase;letter-spacing:.04em}.live-chip.ok{background:#16a34a24;color:var(--ok)}.live-chip.running{background:var(--accent-soft);color:var(--accent)}.live-chip.stale{background:#d9770629;color:#d97706;cursor:help}.example-viz-label,.example-viz-expected{font-size:12px;color:var(--text-dim);margin-bottom:10px}.example-viz-expected{margin:14px 0 0;padding-top:10px;border-top:1px solid var(--border)}.viz-error{margin:18px 0 0;padding:12px 14px;background:#d92b2b14;border-left:3px solid var(--warn);border-radius:8px;font-size:13px;line-height:1.55;color:var(--text);word-break:break-word}.viz-cta{margin:18px 0 0;padding:12px 14px;background:var(--accent-soft);border-left:3px solid var(--accent);border-radius:8px;font-size:13px;line-height:1.55;color:var(--text)}.example-viz-expected code{font-family:var(--mono);color:var(--text)}@media (max-width: 1200px){.workspace{grid-template-columns:minmax(280px,1fr) minmax(340px,1.2fr)}.workspace .pane-viz{grid-column:1 / -1;min-height:46vh}}@media (max-width: 900px){html,body,#root,.app{height:auto;min-height:100%}.workspace{grid-template-columns:1fr;grid-auto-rows:min-content;min-height:0}.workspace .pane-viz{grid-column:auto}.pane-item{max-height:none}.item-scroll{overflow-y:visible;max-height:60vh;overflow-y:auto}.pane-code{min-height:70vh}.pane-viz{min-height:60vh}.app-header{flex-wrap:wrap;gap:10px;padding:10px 12px}.brand-tag{display:none}.header-actions{width:100%;justify-content:space-between;gap:6px}.segment{padding:6px 10px}.controls{gap:8px}.speed{width:100%}.speed input{flex:1}.browser{max-height:88vh}.browser-backdrop{padding:4vh 10px 10px}.browser-row{flex-direction:column;align-items:flex-start;gap:6px}}