:root{--bg-primary:#f8fafc;--bg-secondary:#fff;--text-primary:#0f172a;--text-secondary:#64748b;--border-color:#e2e8f0;--primary-color:#2563eb;--primary-hover:#1d4ed8;--diff-easy:#16a34a;--diff-medium:#d97706;--diff-hard:#dc2626;--btn-run:#64748b;--btn-submit:#16a34a;--btn-ai:#8b5cf6;--shadow-sm:0 1px 2px 0 #0000000d;--shadow-md:0 4px 6px -1px #0000001a, 0 2px 4px -2px #0000001a;--shadow-lg:0 10px 15px -3px #0000001a, 0 4px 6px -4px #0000001a;--radius-sm:4px;--radius-md:8px;--radius-lg:12px}body{background-color:var(--bg-primary);color:var(--text-primary);-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;margin:0;padding:0;font-family:Inter,-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,sans-serif}.navbar{background:var(--bg-secondary);border-bottom:1px solid var(--border-color);z-index:100;height:60px;box-shadow:var(--shadow-sm);justify-content:space-between;align-items:center;padding:0 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td{color:var(--text-primary);border-bottom:1px solid var(--border-color);padding:16px 24px;font-size:14px;transition:background-color .2s}.oj-table tbody tr:hover td{background-color:var(--bg-primary)}.oj-table tbody tr:last-child td{border-bottom:none}.oj-table a{color:var(--text-primary);font-weight:500;text-decoration:none;transition:color .2s}.oj-table a:hover{color:var(--primary-color)}.diff-badge{border-radius:9999px;padding:4px 10px;font-size:12px;font-weight:600;display:inline-block}.diff-easy{color:var(--diff-easy);background-color:#dcfce7}.diff-medium{color:var(--diff-medium);background-color:#fef3c7}.diff-hard{color:var(--diff-hard);background-color:#fee2e2}.problem-layout{background-color:var(--bg-primary);box-sizing:border-box;gap:12px;height:calc(100vh - 60px);padding:12px;display:flex}.problem-card{background:var(--bg-secondary);border-radius:var(--radius-md);box-shadow:var(--shadow-sm);border:1px solid var(--border-color);flex:1;padding:24px;overflow-y:auto}.problem-card h1{color:var(--text-primary);margin-top:0;margin-bottom:16px;font-size:24px}.problem-card .description{color:var(--text-secondary);margin-bottom:24px;font-size:15px;line-height:1.6}.problem-card .examples{background:var(--bg-primary);border-radius:var(--radius-sm);color:var(--text-primary);border:1px solid var(--border-color);margin-bottom:16px;padding:16px;font-family:Fira Code,monospace;font-size:13px}.constraint-badge{background-color:var(--bg-primary);border:1px solid var(--border-color);border-radius:var(--radius-sm);color:var(--text-primary);margin-bottom:8px;margin-right:8px;padding:4px 8px;font-family:Fira Code,monospace;font-size:13px;display:inline-block}.editor-section{flex-direction:column;gap:16px;display:flex}.editor-card{background:var(--bg-secondary);border-radius:var(--radius-md);box-shadow:var(--shadow-sm);border:1px solid var(--border-color);border-radius:10px;flex-direction:column;flex:1;min-height:50vh;display:flex;overflow:hidden}.editor-header{border-bottom:1px solid var(--border-color);background:#f8fafc;align-items:center;padding:8px 16px;display:flex}.editor-toolbar{background:#fff;border:1px solid #e5e7eb;border-bottom:none;border-radius:10px 10px 0 0;justify-content:flex-end;align-items:center;padding:10px 14px;display:flex}.language-select{cursor:pointer;background:#fff;border:1px solid #d1d5db;border-radius:8px;width:140px;height:40px;padding:8px 12px;font-size:14px;font-weight:500}.language-select:hover{border-color:#2563eb}.language-select:focus{border-color:#2563eb;box-shadow:0 0 0 3px #2563eb26}.language-select option{color:#111827;background:#fff;font-size:14px}.verdict-card{background:var(--bg-secondary);border-radius:var(--radius-md);box-shadow:var(--shadow-sm);border:1px solid var(--border-color);flex-direction:column;gap:12px;min-height:200px;padding:16px;display:flex}.verdict-sections{flex:1;gap:16px;display:flex}.verdict-box{background:var(--bg-primary);border-radius:var(--radius-sm);border:1px solid var(--border-color);color:var(--text-secondary);flex:1;padding:12px;font-family:Fira Code,monospace;font-size:13px}.verdict-box strong{color:var(--text-primary);margin-bottom:8px;font-family:Inter,sans-serif;font-size:14px;display:block}.action-buttons{justify-content:flex-end;gap:12px;margin-top:8px;display:flex}.verdict-badge{border-radius:var(--radius-md);padding:6px 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#e5e7eb;border-radius:10px;margin-bottom:15px;padding:15px}.add-btn{color:#fff;cursor:pointer;background:#16a34a;border:none;border-radius:8px;padding:8px 14px}.add-btn:hover{background:#15803d}.delete-btn{color:#fff;cursor:pointer;background:#dc2626;border:none;border-radius:8px;padding:8px 14px}.delete-btn:hover{background:#b91c1c}.submit-btn{color:#fff;cursor:pointer;background:#2563eb;border:none;border-radius:8px;padding:12px 20px;font-weight:600}.submit-btn:hover{background:#1d4ed8}@media (width<=900px){.problem-form-grid{grid-template-columns:1fr}}.page-header{flex-direction:column;justify-content:space-between;align-items:center;margin-bottom:24px;display:flex}.add-problem-btn{color:#fff;background:#2563eb;border-radius:8px;padding:10px 18px;font-weight:600;text-decoration:none;transition:all .2s}.add-problem-btn:hover{background:#1d4ed8;transform:translateY(-1px)}.add-problem-btn:active{transform:translateY(0)}.submission-table-container{width:100%;padding:20px;overflow-x:auto}.submission-table{border-collapse:collapse;background:#fff;border-radius:12px;width:100%;overflow:hidden;box-shadow:0 2px 10px #0000001a}.submission-table thead{color:#fff;background:#1f2937}.submission-table th,.submission-table td{text-align:left;padding:14px 18px}.submission-table th{font-weight:600}.accepted{color:#16a34a;font-weight:600}.rejected{color:#dc2626;font-weight:600}.easy{color:#22c55e;font-weight:600}.medium{color:#f59e0b;font-weight:600}.hard{color:#ef4444;font-weight:600}.submission-table{color:#e2e8f0;background:#1e293b}.submission-table thead{background:#0f172a}.submission-table tbody tr{border-bottom:1px solid #334155}.submission-table tbody tr:hover{background:#293548}