.problem-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 15px;
}

.problem-meta {
    margin-bottom: 20px;
}

.meta-item {
    display: inline-block;
    margin-right: 15px;
    margin-bottom: 10px;
}

.meta-label {
    font-weight: 600;
    color: #7f8c8d;
    margin-right: 5px;
}

.meta-value {
    color: #2c3e50;
}

.task-selector {
    margin: 20px 0;
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

.task-btn {
    padding: 10px 20px;
    background: #ecf0f1;
    border: 2px solid transparent;
    border-radius: 4px;
    cursor: pointer;
    transition: all 0.3s;
    font-size: 0.95rem;
}

.task-btn:hover {
    background: #bdc3c7;
}

.task-btn.active {
    background: #3498db;
    color: white;
    border-color: #2980b9;
}

.task-details {
    margin-top: 20px;
}

.task-section {
    margin-bottom: 25px;
    padding: 15px;
    background: #f8f9fa;
    border-left: 4px solid #3498db;
    border-radius: 4px;
}

.task-section h3 {
    margin-bottom: 10px;
    color: #2c3e50;
    font-size: 1.1rem;
}

.code-block {
    background: #f8f9fa;
    padding: 15px;
    border-radius: 4px;
    overflow-x: auto;
    font-family: 'Monaco', 'Menlo', 'Ubuntu Mono', monospace;
    font-size: 0.9rem;
    border: 1px solid #e1e4e8;
}

.task-items-list {
    list-style: none;
}

.task-items-list li {
    padding: 10px;
    margin-bottom: 8px;
    background: white;
    border-radius: 4px;
    border: 1px solid #e1e4e8;
}

.line-ref {
    display: inline-block;
    padding: 2px 8px;
    background: #3498db;
    color: white;
    border-radius: 3px;
    font-family: monospace;
    font-size: 0.85rem;
    margin-right: 8px;
}

.var-name {
    display: inline-block;
    padding: 2px 8px;
    background: #9b59b6;
    color: white;
    border-radius: 3px;
    font-family: monospace;
    font-size: 0.85rem;
}

.io-section {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 15px;
}

@media (max-width: 768px) {
    .io-section {
        grid-template-columns: 1fr;
    }
}

.navigation-hint {
    margin-top: 20px;
    padding: 15px;
    background: #e8f4f8;
    border-radius: 4px;
    color: #2c3e50;
    font-size: 0.9rem;
}

.test-code-section {
    margin-top: 20px;
}

/* Inline task visualization */
.code-with-tasks {
    position: relative;
}

.task-marker {
    display: inline-block;
    margin-left: 10px;
    padding: 2px 8px;
    background: #9b59b6;
    color: white;
    border-radius: 3px;
    font-size: 0.75rem;
    font-weight: 600;
    cursor: crosshair;
}

/* Coverage coloring on lineno spans */
td.linenos .normal.line-executed {
    background-color: #d4edda !important;
    color: #155724 !important;
}

td.linenos .normal.line-not-executed {
    background-color: #f8d7da !important;
    color: #721c24 !important;
}

/* Coverage legend */
.coverage-legend {
    margin: 10px 0;
    padding: 10px 15px;
    background: #f8f9fa;
    border-left: 4px solid #28a745;
    border-radius: 4px;
    font-size: 0.85rem;
    display: none;
}

.coverage-legend-item {
    display: inline-block;
    margin-right: 18px;
}

.coverage-swatch {
    display: inline-block;
    width: 12px;
    height: 12px;
    border-radius: 2px;
    margin-right: 4px;
    vertical-align: middle;
}

/* Ground truth answer badge */
.gt-answer {
    display: inline-block;
    margin-left: 10px;
    padding: 2px 8px;
    background: #17a2b8;
    color: white;
    border-radius: 3px;
    font-family: monospace;
    font-size: 0.82rem;
    font-weight: 600;
}

.gt-answer.loading {
    background: #6c757d;
}

/* SVG arrow overlay */
#arrow-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    overflow: visible;
    z-index: 10;
}

.exec-arrow {
    fill: none;
    stroke: #e67e22;
    stroke-width: 2.5;
    stroke-dasharray: none;
    opacity: 0.9;
}

.exec-arrow-head {
    fill: #e67e22;
    opacity: 0.9;
}

/* CRUXEval answer highlight */
.crux-answer {
    border-left: 4px solid #17a2b8 !important;
    background: #e8f6f8 !important;
}

/* Before/after diff view */
.diff-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}

@media (max-width: 1024px) {
    .diff-container {
        grid-template-columns: 1fr;
    }
}

.diff-panel {
    overflow-x: auto;
}

.diff-panel h3 {
    margin-bottom: 10px;
    font-size: 1.1rem;
}

.diff-panel h3 .diff-label-buggy {
    color: #e74c3c;
}

.diff-panel h3 .diff-label-fixed {
    color: #27ae60;
}

.bug-info {
    margin-bottom: 15px;
    padding: 12px 15px;
    border-left: 4px solid #e74c3c;
    background: #fdf2f2;
    border-radius: 4px;
}

.bug-info .bug-category {
    display: inline-block;
    padding: 2px 8px;
    background: #e74c3c;
    color: white;
    border-radius: 3px;
    font-size: 0.82rem;
    font-weight: 600;
    margin-right: 8px;
}

.bug-info .bug-subtype {
    display: inline-block;
    padding: 2px 8px;
    background: #c0392b;
    color: white;
    border-radius: 3px;
    font-size: 0.82rem;
    font-weight: 600;
}

/* Multi-language view */
.lang-tabs {
    display: flex;
    gap: 0;
    border-bottom: 2px solid #e1e4e8;
    margin-bottom: 0;
}

.lang-tab {
    padding: 10px 20px;
    background: #f8f9fa;
    border: 1px solid #e1e4e8;
    border-bottom: none;
    cursor: pointer;
    font-size: 0.95rem;
    font-weight: 500;
    transition: all 0.2s;
    border-radius: 4px 4px 0 0;
    margin-right: 2px;
}

.lang-tab:hover {
    background: #e8f4f8;
}

.lang-tab.active {
    background: white;
    border-bottom: 2px solid white;
    margin-bottom: -2px;
    color: #3498db;
    font-weight: 600;
}

.lang-code-panel {
    display: none;
}

.lang-code-panel.active {
    display: block;
}

/* BigOBench complexity display */
.complexity-badges {
    display: flex;
    gap: 20px;
    flex-wrap: wrap;
}

.complexity-item {
    display: flex;
    align-items: center;
    gap: 10px;
}

.complexity-label {
    font-weight: 600;
    color: #7f8c8d;
    font-size: 0.95rem;
}

.complexity-value {
    display: inline-block;
    padding: 6px 16px;
    background: #2c3e50;
    color: #f1c40f;
    border-radius: 4px;
    font-family: 'Monaco', 'Menlo', 'Ubuntu Mono', monospace;
    font-size: 1.1rem;
    font-weight: 600;
}

/* Diff view (GitHub-style table with line numbers) */
.diff-view {
    font-family: 'Monaco', 'Menlo', 'Ubuntu Mono', monospace;
    font-size: 0.85rem;
    line-height: 1.5;
    overflow-x: auto;
    border: 1px solid #e1e4e8;
    border-radius: 4px;
}

.diff-table {
    border-collapse: collapse;
    width: 100%;
}

.diff-table td {
    padding: 0 8px;
    white-space: pre;
    vertical-align: top;
}

.diff-ln {
    width: 1%;
    min-width: 40px;
    color: #959da5;
    text-align: right;
    user-select: none;
    font-size: 0.8rem;
    padding: 0 6px !important;
    border-right: 1px solid #e1e4e8;
}

.diff-tr-add td { background: #e6ffec; }
.diff-td-add { color: #24292e; }
.diff-tr-add .diff-ln { background: #ccffd8; color: #22863a; }

.diff-tr-del td { background: #ffebe9; }
.diff-td-del { color: #24292e; }
.diff-tr-del .diff-ln { background: #ffd7d5; color: #cb2431; }

.diff-tr-ctx td { background: white; }
.diff-td-ctx { color: #586069; }

.diff-tr-hunk td {
    background: #f1f8ff;
    color: #0366d6;
    font-weight: 600;
    padding: 4px 8px;
}

.diff-tr-header td {
    background: #fafbfc;
    color: #6a737d;
    font-weight: 600;
    padding: 4px 8px;
    border-bottom: 1px solid #e1e4e8;
}

/* Diff file sections (GitHub-style per-file headers) */
.diff-file-section {
    margin-bottom: 16px;
    border: 1px solid #d0d7de;
    border-radius: 6px;
    overflow: hidden;
}

.diff-file-section .diff-view {
    border: none;
    border-radius: 0;
}

.diff-file-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 8px 12px;
    background: #f6f8fa;
    border-bottom: 1px solid #d0d7de;
    font-family: 'Monaco', 'Menlo', 'Ubuntu Mono', monospace;
    font-size: 0.85rem;
}

.diff-file-path {
    color: #24292f;
    font-weight: 600;
    word-break: break-all;
}

.diff-file-stats {
    white-space: nowrap;
    margin-left: 12px;
    font-size: 0.8rem;
}

.diff-stat-add { color: #1a7f37; font-weight: 600; }
.diff-stat-del { color: #cf222e; font-weight: 600; margin-left: 6px; }

/* GitHub links bar */
.gh-links-bar {
    display: flex;
    gap: 12px;
    align-items: center;
    flex-wrap: wrap;
}

.gh-link {
    display: inline-block;
    padding: 6px 14px;
    background: #f6f8fa;
    border: 1px solid #d0d7de;
    border-radius: 6px;
    color: #0969da;
    text-decoration: none;
    font-size: 0.9rem;
    font-weight: 500;
    transition: background 0.15s, border-color 0.15s;
}

.gh-link:hover {
    background: #ddf4ff;
    border-color: #0969da;
}

/* Issue / problem statement */
.issue-statement {
    line-height: 1.7;
    padding: 10px;
    white-space: pre-wrap;
    word-wrap: break-word;
    max-height: 500px;
    overflow-y: auto;
    background: #f8f9fa;
    border: 1px solid #e1e4e8;
    border-radius: 4px;
    font-size: 0.9rem;
}

.test-id-list {
    list-style: none;
    padding: 0;
}

.test-id-list li {
    padding: 4px 8px;
    margin-bottom: 4px;
    background: #f8f9fa;
    border-radius: 3px;
    font-family: monospace;
    font-size: 0.82rem;
    border-left: 3px solid #e74c3c;
}

.test-id-list li.pass-to-pass {
    border-left-color: #27ae60;
}

/* Fill-in-the-Middle (SAFIM) view */
.fim-hole-marker {
    display: inline-block;
    padding: 4px 16px;
    background: #e74c3c;
    color: white;
    border-radius: 4px;
    font-family: monospace;
    font-weight: 600;
    font-size: 0.9rem;
    margin: 4px 0;
}

.fim-answer {
    padding: 15px;
    background: #e8f6e8;
    border-left: 4px solid #27ae60;
    border-radius: 4px;
    font-family: monospace;
    font-size: 0.9rem;
}

.fim-merged-legend {
    margin: 8px 0;
    padding: 6px 12px;
    background: #f8f9fa;
    border-radius: 4px;
    font-size: 0.85rem;
    color: #555;
}

/* Vulnerability view */
.vuln-status {
    display: inline-block;
    padding: 4px 12px;
    border-radius: 4px;
    font-size: 0.85rem;
    font-weight: 600;
}

.vuln-status-vulnerable {
    background: #e74c3c;
    color: white;
}

.vuln-status-patched {
    background: #27ae60;
    color: white;
}

.cwe-badge {
    display: inline-block;
    padding: 4px 12px;
    background: #2c3e50;
    color: #e74c3c;
    border-radius: 4px;
    font-family: monospace;
    font-size: 0.85rem;
    font-weight: 600;
}