@import "https://fonts.googleapis.com/css2?family=Outfit:wght@400;500;600;700&family=JetBrains+Mono:wght@400;500&display=swap";:root{--bg:#1e1e2e;--surface:#181825;--surface-2:#1e1e2e;--surface-3:#313244;--border:#313244;--border-bright:#45475a;--accent:#89b4fa;--accent-hi:#b4d0ff;--accent-dim:#89b4fa1f;--accent-glow:#89b4fa38;--success:#a6e3a1;--success-dim:#a6e3a124;--error:#f38ba8;--error-dim:#f38ba824;--warn:#fab387;--easy:#a6e3a1;--medium:#f9e2af;--hard:#f38ba8;--text:#cdd6f4;--text-bright:#cdd6f4;--text-dim:#6c7086;--text-muted:#9399b2;--text-code:#a6adc8;--font-ui:"Outfit", system-ui, sans-serif;--font-mono:"JetBrains Mono", "Fira Code", monospace;--sidebar-w:230px;--sidebar-collapsed-w:52px;--header-h:52px;--radius:6px;--radius-sm:4px}*,:before,:after{box-sizing:border-box;margin:0;padding:0}html,body,#root{height:100%;overflow:hidden}body{background:var(--bg);color:var(--text);font-family:var(--font-ui);-webkit-font-smoothing:antialiased;font-size:14px}.app-root{grid-template-rows:100vh;height:100vh;transition:grid-template-columns .2s;display:grid;overflow:hidden}.sidebar{background:var(--surface);border-right:1px solid var(--border);flex-direction:column;transition:width .2s;display:flex;overflow:hidden}.sidebar-logo{height:var(--header-h);border-bottom:1px solid var(--border);flex-shrink:0;justify-content:space-between;align-items:center;padding:0 14px 0 20px;display:flex}.sidebar.collapsed .sidebar-logo{justify-content:center;padding:0}.logo-text{color:var(--text-bright);letter-spacing:.04em;font-size:14px;font-weight:700}.sidebar-toggle{border:1px solid var(--border);color:var(--text-dim);border-radius:var(--radius-sm);cursor:pointer;background:0 0;flex-shrink:0;justify-content:center;align-items:center;width:26px;height:26px;font-size:15px;line-height:1;transition:color .15s,border-color .15s,background .15s;display:flex}.sidebar-toggle:hover{color:var(--text);border-color:var(--border-bright);background:var(--surface-3)}.sidebar.collapsed .sidebar-toggle{border-color:#0000}.sidebar-section-label{letter-spacing:.1em;text-transform:uppercase;color:var(--text-dim);padding:14px 20px 8px;font-size:10px;font-weight:600}.problem-list{flex:1;padding:4px 0;overflow-y:auto}.problem-item{cursor:pointer;text-align:left;background:0 0;border:none;border-left:2px solid #0000;align-items:flex-start;gap:10px;width:100%;padding:10px 20px;transition:background .12s;display:flex}.sidebar.collapsed .problem-item{border-left:2px solid #0000;justify-content:center;gap:0;padding:10px 0}.problem-item:hover{background:var(--surface-3)}.problem-item.active{background:var(--accent-dim);border-left-color:var(--accent)}.sidebar.collapsed .problem-item.active{border-left-color:var(--accent)}.problem-number{font-family:var(--font-mono);color:var(--text-dim);flex-shrink:0;padding-top:1px;font-size:11px}.problem-item.active .problem-number{color:var(--accent)}.problem-item-content{flex-direction:column;gap:5px;min-width:0;display:flex}.problem-item-title{color:var(--text-muted);word-break:break-word;font-size:13px;font-weight:500;line-height:1.35}.problem-item.active .problem-item-title{color:var(--text-bright)}.sidebar-footer{border-top:1px solid var(--border);color:var(--text-dim);flex-shrink:0;align-items:center;gap:8px;padding:14px 20px;font-size:11px;display:flex}.sidebar.collapsed .sidebar-footer{justify-content:center;padding:14px 0}.footer-dot{background:var(--success);border-radius:50%;flex-shrink:0;width:6px;height:6px}.diff-badge{font-size:10px;font-weight:600;font-family:var(--font-ui);letter-spacing:.04em;border-radius:3px;width:fit-content;padding:2px 7px;display:inline-block}.diff-badge.easy{color:var(--easy);background:#a6e3a124}.diff-badge.medium{color:var(--medium);background:#f9e2af24}.diff-badge.hard{color:var(--hard);background:#f38ba824}.problem-panel{border-right:1px solid var(--border);background:var(--bg);flex-direction:column;display:flex;overflow:hidden}.problem-header{border-bottom:1px solid var(--border);flex-shrink:0;padding:22px 26px 16px}.problem-title{color:var(--text-bright);margin-bottom:10px;font-size:17px;font-weight:700;line-height:1.4}.problem-meta{align-items:center;gap:8px;display:flex}.category-tag{color:var(--accent);background:var(--accent-dim);border-radius:3px;padding:2px 8px;font-size:11px;font-weight:500}.problem-body{scrollbar-width:thin;scrollbar-color:var(--border) transparent;flex:1;padding:22px 26px 32px;overflow-y:auto}.problem-description{color:var(--text-muted);font-size:14px;line-height:1.75}.problem-description p+p{margin-top:12px}.problem-description code{font-family:var(--font-mono);background:var(--surface-3);color:var(--text-code);border-radius:var(--radius-sm);padding:2px 5px;font-size:12.5px}.problem-description strong{color:var(--text-bright);font-weight:600}.problem-description em{color:var(--accent);font-style:italic}.section-label{letter-spacing:.12em;text-transform:uppercase;color:var(--text-dim);align-items:center;gap:8px;margin-top:24px;margin-bottom:12px;font-size:10px;font-weight:600;display:flex}.problem-body>.section-label:first-child{margin-top:0}.section-sublabel{letter-spacing:.06em;color:var(--success);background:var(--success-dim);text-transform:uppercase;border-radius:3px;padding:1px 6px;font-size:10px;font-weight:500}.example-block{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);margin-bottom:10px;padding:14px 16px}.example-num{letter-spacing:.08em;text-transform:uppercase;color:var(--text-dim);margin-bottom:10px;font-size:10px;font-weight:600}.example-io{flex-direction:column;gap:7px;display:flex}.io-row{align-items:baseline;gap:10px;display:flex}.io-label{text-transform:uppercase;letter-spacing:.08em;color:var(--text-dim);flex-shrink:0;width:48px;font-size:10px;font-weight:600}.io-value{font-family:var(--font-mono);color:var(--text-code);background:var(--surface-3);border-radius:var(--radius-sm);word-break:break-all;padding:3px 8px;font-size:12.5px}.example-explanation{color:var(--text-dim);border-top:1px solid var(--border);margin-top:10px;padding-top:10px;font-size:13px;line-height:1.65}.example-explanation b{color:var(--text-muted);font-weight:500}.constraints-list{flex-direction:column;gap:4px;margin-bottom:24px;list-style:none;display:flex}.constraints-list li{font-family:var(--font-mono);color:var(--text-muted);border-left:2px solid var(--border-bright);background:var(--surface);padding:5px 12px;font-size:12px}.test-cases-grid{grid-template-columns:1fr 1fr;gap:8px;margin-bottom:24px;display:grid}.tc-card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);flex-direction:column;gap:4px;padding:11px 13px;display:flex}.tc-label{letter-spacing:.08em;text-transform:uppercase;color:var(--text-dim);font-size:10px;font-weight:600}.tc-input{font-family:var(--font-mono);color:var(--text-muted);word-break:break-all;font-size:11px;line-height:1.5}.tc-arrow{color:var(--text-dim);font-size:11px}.tc-expected{font-family:var(--font-mono);color:var(--accent);font-size:12.5px;font-weight:500}.hints-section{margin-top:0}.hints-list{flex-direction:column;gap:8px;display:flex}.hint-item{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);overflow:hidden}.hint-item.unlocked{border-color:var(--border-bright)}.hint-item p{color:var(--text-muted);padding:13px 15px;font-size:13.5px;line-height:1.7}.hint-item p code{font-family:var(--font-mono);background:var(--surface-3);color:var(--text-code);border-radius:3px;padding:1px 5px;font-size:12px}.hint-item p em{color:var(--accent);font-style:italic}.unlock-hint-btn{background:var(--accent-dim);width:100%;color:var(--accent);font-family:var(--font-ui);cursor:pointer;text-align:left;border:none;padding:11px 15px;font-size:13px;font-weight:500;transition:background .15s}.unlock-hint-btn:hover{background:var(--accent-glow)}.hint-locked{color:var(--text-dim);padding:11px 15px;font-size:12px;display:block}.workspace{background:var(--bg);flex-direction:column;display:flex;overflow:hidden}.workspace-header{height:var(--header-h);border-bottom:1px solid var(--border);background:var(--surface);flex-shrink:0;align-items:center;gap:12px;padding:0 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.15s;display:inline-flex}.btn:disabled{opacity:.38;cursor:default}.btn-icon{font-size:11px;line-height:1}.btn-run{background:var(--success-dim);color:var(--success);border-color:#a6e3a140}.btn-run:hover:not(:disabled){background:#a6e3a138;border-color:#a6e3a166}.btn-submit{background:var(--accent-dim);color:var(--accent);border-color:#89b4fa40}.btn-submit:hover:not(:disabled){background:var(--accent-glow);border-color:#89b4fa66}.btn-custom{background:var(--surface-3);border-color:var(--border);color:var(--text-dim)}.btn-custom:hover:not(:disabled),.btn-custom.active{background:var(--surface-2);color:var(--text);border-color:var(--border-bright)}.runtime-pills{gap:6px;margin-left:auto;display:flex}.rt-pill{font-family:var(--font-mono);border:1px solid var(--border);color:var(--text-dim);background:var(--surface-3);border-radius:3px;padding:3px 8px;font-size:11px;transition:all .3s}.rt-pill.ok{color:var(--success);background:var(--success-dim);border-color:#a6e3a14d}.rt-pill.error{color:var(--error);background:var(--error-dim);border-color:#f38ba84d}.rt-pill.loading{animation:1.5s ease-in-out infinite pulse}@keyframes pulse{0%,to{opacity:1}50%{opacity:.4}}.custom-drawer{border-bottom:1px solid var(--border);background:var(--surface);flex-direction:column;flex-shrink:0;gap:10px;padding:14px 16px;animation:.15s slideDown;display:flex}@keyframes slideDown{0%{opacity:0;transform:translateY(-6px)}to{opacity:1;transform:translateY(0)}}.custom-drawer-header{align-items:baseline;gap:12px;display:flex}.custom-label{letter-spacing:.08em;text-transform:uppercase;color:var(--text-dim);font-size:11px;font-weight:600}.custom-format{font-family:var(--font-mono);color:var(--text-dim);white-space:pre;font-size:11px}.custom-textarea{background:var(--bg);border:1px solid var(--border);border-radius:var(--radius);width:100%;min-height:72px;max-height:120px;color:var(--text-code);font-family:var(--font-mono);resize:vertical;outline:none;padding:10px 12px;font-size:13px;transition:border-color .15s}.custom-textarea:focus{border-color:var(--accent)}.custom-run-btn{align-self:flex-start}.editor-area{flex:1;min-height:0;overflow:hidden}.spinner{border:2px solid;border-top-color:#0000;border-radius:50%;width:12px;height:12px;animation:.6s linear infinite spin;display:inline-block}@keyframes spin{to{transform:rotate(360deg)}}.results-panel{border-top:1px solid var(--border);background:var(--surface);flex-direction:column;flex-shrink:0;min-height:120px;max-height:44%;animation:.18s riseUp;display:flex}@keyframes riseUp{0%{opacity:0;transform:translateY(8px)}to{opacity:1;transform:translateY(0)}}.results-header{border-bottom:1px solid var(--border);flex-shrink:0;align-items:center;gap:10px;padding:9px 16px;display:flex}.results-title{letter-spacing:.1em;text-transform:uppercase;color:var(--text-dim);font-size:11px;font-weight:600}.summary-badge{border-radius:12px;padding:2px 10px;font-size:12px;font-weight:600}.summary-badge.all-pass{color:var(--success);background:var(--success-dim)}.summary-badge.some-fail{color:var(--error);background:var(--error-dim)}.close-results{color:var(--text-dim);cursor:pointer;border-radius:var(--radius-sm);background:0 0;border:none;margin-left:auto;padding:2px 6px;font-size:14px;transition:color .15s}.close-results:hover{color:var(--text)}.results-body{scrollbar-width:thin;scrollbar-color:var(--border) transparent;flex:1;overflow-y:auto}.output-section{border-bottom:1px solid var(--border)}.output-section-label,.result-section-label{letter-spacing:.1em;text-transform:uppercase;color:var(--text-dim);padding:7px 16px 4px;font-size:10px;font-weight:600}.test-result-list{flex-direction:column;display:flex}.tr-item{border-bottom:1px solid var(--border);align-items:center;gap:12px;padding:10px 16px;animation:.1s forwards fadeIn;display:flex}.tr-item:last-child{border-bottom:none}.tr-status{font-family:var(--font-mono);letter-spacing:.08em;border-radius:3px;flex-shrink:0;padding:3px 8px;font-size:10px;font-weight:700}.tr-item.pass .tr-status{color:var(--success);background:var(--success-dim)}.tr-item.fail .tr-status{color:var(--error);background:var(--error-dim)}.tr-detail{font-family:var(--font-mono);color:var(--text-dim);flex-wrap:wrap;align-items:center;gap:10px;font-size:12.5px;display:flex}.tr-case-num{color:var(--text-dim);padding-right:2px;font-size:12px}.tr-detail span{align-items:center;gap:5px;display:flex}.tr-detail code{color:var(--text-code);background:var(--surface-3);font-family:var(--font-mono);border-radius:3px;padding:1px 6px;font-size:12px}code.got-wrong{color:var(--error)!important;background:var(--error-dim)!important}@keyframes fadeIn{0%{opacity:0;transform:translate(-4px)}to{opacity:1;transform:translate(0)}}.raw-output{font-family:var(--font-mono);white-space:pre-wrap;word-break:break-word;padding:12px 16px;font-size:13px;line-height:1.65}.out-stdout{color:var(--text-bright)}.out-stderr{color:var(--error)}.out-info{color:var(--text-dim)}.out-warn{color:var(--warn)}::-webkit-scrollbar{width:5px;height:5px}::-webkit-scrollbar-track{background:0 0}::-webkit-scrollbar-thumb{background:var(--border-bright);border-radius:2px}::-webkit-scrollbar-thumb:hover{background:var(--text-dim)}