/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* Color Palette */
    --primary-color: #0066cc;
    --primary-hover: #0052a3;
    --secondary-color: #6c757d;
    --secondary-hover: #5a6268;

    /* Status Colors - Table */
    --solved-bg: #d4edda;
    --solved-border: #c3e6cb;
    --solved-text: #155724;
    --attempted-bg: #fff3cd;
    --attempted-border: #ffeaa7;
    --attempted-text: #856404;
    --unsolved-bg: #ffffff;
    --unsolved-border: #d1d5da;
    --unsolved-text: #586069;

    /* Status Colors - Progress Grid (Brighter) */
    --grid-solved-bg: #28a745;
    --grid-solved-border: #1e7e34;
    --grid-attempted-bg: #ffc107;
    --grid-attempted-border: #e0a800;
    --grid-unsolved-bg: #e1e4e8;
    --grid-unsolved-border: #d1d5da;

    /* UI Colors */
    --bg-color: #f6f8fa;
    --card-bg: #ffffff;
    --border-color: #e1e4e8;
    --text-primary: #24292e;
    --text-secondary: #586069;
    --shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 4px 6px rgba(0, 0, 0, 0.1);

    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;

    /* Border Radius */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-primary);
    line-height: 1.6;
    font-size: 14px;
}

.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: var(--spacing-lg);
}

/* Compact Header */
.compact-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-lg);
    background: var(--card-bg);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow);
    margin-bottom: var(--spacing-lg);
    flex-wrap: wrap;
    gap: var(--spacing-md);
}

.header-left {
    display: flex;
    align-items: center;
    gap: var(--spacing-lg);
}

.compact-header h1 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
    margin: 0;
}

.header-right {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.username-input {
    padding: var(--spacing-sm) var(--spacing-md);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    font-size: 0.95rem;
    min-width: 200px;
    transition: border-color 0.2s;
}

.username-input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(0, 102, 204, 0.1);
}

.btn-compact {
    padding: var(--spacing-sm) var(--spacing-lg);
    font-size: 0.9rem;
}

.btn-compact-narrow {
    padding: var(--spacing-sm) var(--spacing-md);
    font-size: 0.9rem;
}

.btn-icon {
    padding: var(--spacing-sm) var(--spacing-md);
    border: 1px solid var(--border-color);
    background: var(--card-bg);
    color: var(--primary-color);
    font-size: 1.2rem;
    font-weight: 700;
    cursor: pointer;
    border-radius: var(--radius-sm);
    transition: all 0.2s;
}

.btn-icon:hover {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

.btn-link {
    background: transparent;
    color: var(--text-secondary);
    border: none;
    padding: var(--spacing-sm) var(--spacing-md);
    font-size: 0.85rem;
    cursor: pointer;
    transition: color 0.2s;
}

.btn-link:hover {
    color: var(--primary-color);
    background: transparent;
    transform: none;
}

.btn-sm {
    padding: 4px var(--spacing-sm);
    font-size: 0.8rem;
}

/* Platform Tabs */
.platform-tabs {
    display: flex;
    gap: var(--spacing-xs);
    background: var(--bg-color);
    padding: 4px;
    border-radius: var(--radius-sm);
}

.platform-tab {
    padding: var(--spacing-sm) var(--spacing-md);
    border: none;
    background: transparent;
    color: var(--text-secondary);
    font-size: 0.9rem;
    font-weight: 500;
    cursor: pointer;
    border-radius: var(--radius-sm);
    transition: all 0.2s;
}

.platform-tab:hover:not(:disabled) {
    background: rgba(0, 102, 204, 0.1);
    color: var(--primary-color);
}

.platform-tab.active {
    background: var(--primary-color);
    color: white;
}

.platform-tab:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

/* Compact Filters Panel */
.filters-panel-compact {
    background: var(--card-bg);
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow);
    margin-bottom: var(--spacing-lg);
    position: relative;
}

.btn-clear-corner {
    position: absolute;
    top: var(--spacing-sm);
    right: var(--spacing-sm);
    background: transparent;
    border: none;
    color: var(--text-secondary);
    font-size: 1.5rem;
    line-height: 1;
    cursor: pointer;
    padding: var(--spacing-xs);
    border-radius: var(--radius-sm);
    transition: all 0.2s;
    width: 24px;
    height: 24px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.btn-clear-corner:hover {
    background: var(--bg-color);
    color: var(--primary-color);
}

.filters-row {
    display: flex;
    align-items: center;
    gap: var(--spacing-lg);
    flex-wrap: wrap;
    padding: var(--spacing-sm) 0;
}

.filters-row:not(:last-child) {
    margin-bottom: var(--spacing-sm);
}

.filter-group-inline {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.filter-label {
    font-weight: 600;
    color: var(--text-secondary);
    font-size: 0.85rem;
    white-space: nowrap;
}

.checkbox-group-inline {
    display: flex;
    gap: var(--spacing-sm);
}

.checkbox-label {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    cursor: pointer;
    font-size: 0.9rem;
}

.checkbox-label input[type="checkbox"] {
    cursor: pointer;
    width: 14px;
    height: 14px;
}

.input-compact {
    padding: 6px var(--spacing-sm);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    font-size: 0.85rem;
    width: 90px;
    transition: border-color 0.2s;
}

.input-compact[type="date"] {
    width: 150px;
}

.input-tag {
    padding: 6px var(--spacing-sm);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    font-size: 0.85rem;
    width: 180px;
    transition: border-color 0.2s;
}

.input-compact:focus,
.input-tag:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 2px rgba(0, 102, 204, 0.1);
}

.separator {
    color: var(--text-secondary);
    font-weight: 300;
}

.filter-actions {
    display: flex;
    gap: var(--spacing-sm);
    margin-left: auto;
}

.tags-section {
    flex: 1;
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

/* Tags Container and Chips */
.tags-container-inline {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
    align-items: center;
}

.tag-chip {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: 4px var(--spacing-sm);
    background-color: var(--primary-color);
    color: white;
    border-radius: var(--radius-sm);
    font-size: 0.8rem;
    font-weight: 500;
    transition: all 0.2s;
}

.tag-chip:hover {
    background-color: var(--primary-hover);
}

.tag-chip .tag-text {
    user-select: none;
}

.tag-chip .tag-remove {
    cursor: pointer;
    background: rgba(255, 255, 255, 0.2);
    border: none;
    color: white;
    width: 18px;
    height: 18px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.9rem;
    font-weight: 700;
    padding: 0;
    line-height: 1;
    transition: background-color 0.2s;
}

.tag-chip .tag-remove:hover {
    background: rgba(255, 255, 255, 0.3);
}

/* Buttons */
.action-buttons {
    grid-column: 1 / -1;
    display: flex;
    gap: var(--spacing-md);
    flex-wrap: wrap;
}

.btn {
    padding: var(--spacing-sm) var(--spacing-lg);
    border: none;
    border-radius: var(--radius-sm);
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
    flex: 1;
    min-width: 150px;
}

.btn-primary {
    background-color: var(--primary-color);
    color: white;
}

.btn-primary:hover {
    background-color: var(--primary-hover);
    transform: translateY(-2px);
    box-shadow: var(--shadow);
}

.btn-secondary {
    background-color: var(--secondary-color);
    color: white;
}

.btn-secondary:hover {
    background-color: var(--secondary-hover);
    transform: translateY(-2px);
    box-shadow: var(--shadow);
}

.btn-tertiary {
    background-color: var(--unsolved-bg);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

.btn-tertiary:hover {
    background-color: var(--border-color);
    transform: translateY(-2px);
    box-shadow: var(--shadow);
}

.btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
}

/* Compact Stats Bar */
.stats-bar-compact {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    background: var(--bg-color);
    padding: var(--spacing-sm) var(--spacing-lg);
    border-radius: var(--radius-sm);
    margin-bottom: var(--spacing-lg);
    font-size: 0.9rem;
}

.stat-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    color: var(--text-primary);
    font-weight: 500;
}

.stat-item.stat-solved {
    color: var(--solved-text);
}

.stat-item.stat-attempted {
    color: var(--attempted-text);
}

.stat-icon {
    font-size: 1rem;
}

.stat-divider {
    color: var(--border-color);
    font-weight: 300;
}

/* Main Content */
.main-content {
    display: grid;
    grid-template-columns: 2.33fr 1fr;
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
    min-width: 0;
}

/* Problem Table */
.problem-table-container {
    background: var(--card-bg);
    padding: var(--spacing-lg);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow);
    min-width: 0;
}

.problem-table-container h2 {
    font-size: 1.3rem;
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
}

.table-wrapper {
    overflow-x: auto;
}

#problem-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.9rem;
}

#problem-table thead {
    background-color: var(--bg-color);
    position: sticky;
    top: 0;
    z-index: 10;
}

#problem-table th {
    padding: var(--spacing-md);
    text-align: left;
    font-weight: 700;
    border-bottom: 2px solid var(--border-color);
    white-space: nowrap;
}

#problem-table th.sortable {
    cursor: pointer;
    user-select: none;
}

#problem-table th.sortable:hover {
    background-color: var(--border-color);
}

.sort-icon {
    display: inline-block;
    margin-left: var(--spacing-xs);
    opacity: 0.3;
}

.sort-icon::after {
    content: '⇅';
}

th.sorted-asc .sort-icon::after {
    content: '↑';
    opacity: 1;
}

th.sorted-desc .sort-icon::after {
    content: '↓';
    opacity: 1;
}

#problem-table td {
    padding: var(--spacing-md);
    border-bottom: 1px solid var(--border-color);
}

#problem-table tbody tr {
    transition: all 0.2s;
}

#problem-table tbody tr:hover {
    background-color: var(--bg-color);
    transform: scale(1.01);
    box-shadow: var(--shadow);
}

/* Status-based row coloring */
#problem-table tbody tr.solved {
    background-color: var(--solved-bg);
}

#problem-table tbody tr.attempted {
    background-color: var(--attempted-bg);
}

#problem-table tbody tr.unsolved {
    background-color: var(--unsolved-bg);
}

.problem-name {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
}

.problem-name:hover {
    text-decoration: underline;
}

.contest-link {
    color: var(--text-primary);
    text-decoration: none;
}

.contest-link:hover {
    color: var(--primary-color);
    text-decoration: underline;
}

.problem-tags {
    display: flex;
    gap: var(--spacing-xs);
    flex-wrap: wrap;
}

.tag {
    padding: var(--spacing-xs) var(--spacing-sm);
    background-color: var(--bg-color);
    border-radius: var(--radius-sm);
    font-size: 0.75rem;
    color: var(--text-secondary);
    border: 1px solid var(--border-color);
}

.status-badge {
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-sm);
    font-size: 0.8rem;
    font-weight: 600;
    text-transform: uppercase;
}

.status-badge.solved {
    background-color: var(--solved-text);
    color: white;
}

.status-badge.attempted {
    background-color: var(--attempted-text);
    color: white;
}

.status-badge.unsolved {
    background-color: var(--unsolved-text);
    color: white;
}

/* Progress Grid */
.progress-grid-container {
    background: var(--card-bg);
    padding: var(--spacing-lg);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow);
    min-width: 0;
    width: 100%;
    max-width: 100%;
    align-self: start;
}

.progress-grid-container h2 {
    font-size: 1.3rem;
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
}

.progress-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(12px, 1fr));
    gap: 4px;
    margin-bottom: var(--spacing-md);
    width: 100%;
    box-sizing: border-box;
}

.grid-cell {
    aspect-ratio: 1;
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: all 0.2s;
    position: relative;
    box-sizing: border-box;
}

.grid-cell.solved {
    background-color: var(--grid-solved-bg);
}

.grid-cell.attempted {
    background-color: var(--grid-attempted-bg);
}

.grid-cell.unsolved {
    background-color: var(--grid-unsolved-bg);
}

.grid-cell:hover {
    transform: scale(1.3);
    box-shadow: var(--shadow-lg);
    z-index: 100;
}

/* Tooltip */
.grid-cell::after {
    content: attr(data-tooltip);
    position: absolute;
    bottom: 120%;
    left: 50%;
    transform: translateX(-50%);
    background-color: var(--text-primary);
    color: white;
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--radius-sm);
    font-size: 0.8rem;
    white-space: nowrap;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.2s;
    z-index: 1000;
}

.grid-cell:hover::after {
    opacity: 1;
}

.grid-legend {
    display: flex;
    justify-content: center;
    gap: var(--spacing-lg);
    flex-wrap: wrap;
}

.legend-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 0.9rem;
}

.legend-color {
    width: 20px;
    height: 20px;
    border-radius: var(--radius-sm);
    border: 1px solid var(--border-color);
}

.legend-color.solved {
    background-color: var(--grid-solved-bg);
}

.legend-color.attempted {
    background-color: var(--grid-attempted-bg);
}

.legend-color.unsolved {
    background-color: var(--grid-unsolved-bg);
}

/* Loading Spinner */
.loading-spinner {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    z-index: 9999;
    backdrop-filter: blur(4px);
}

.loading-spinner.hidden {
    display: none;
}

.spinner {
    width: 60px;
    height: 60px;
    border: 6px solid rgba(255, 255, 255, 0.3);
    border-top-color: white;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

.loading-spinner p {
    color: white;
    font-size: 1.2rem;
    margin-top: var(--spacing-md);
    font-weight: 600;
}

/* Error Message */
.error-message {
    position: fixed;
    top: var(--spacing-lg);
    right: var(--spacing-lg);
    max-width: 400px;
    z-index: 10000;
    animation: slideIn 0.3s ease-out;
}

.error-message.hidden {
    display: none;
}

@keyframes slideIn {
    from {
        transform: translateX(100%);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

.error-content {
    background-color: #f8d7da;
    border: 1px solid #f5c6cb;
    border-left: 4px solid #dc3545;
    color: #721c24;
    padding: var(--spacing-md);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-lg);
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.error-icon {
    background-color: #dc3545;
    color: white;
    width: 24px;
    height: 24px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    flex-shrink: 0;
}

.error-text {
    flex: 1;
    font-size: 0.9rem;
}

.error-close {
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: #721c24;
    padding: 0;
    width: 24px;
    height: 24px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.error-close:hover {
    opacity: 0.7;
}

/* Success Message (variant of error message) */
.error-message.success .error-content {
    background-color: #d4edda;
    border: 1px solid #c3e6cb;
    border-left: 4px solid #28a745;
    color: #155724;
}

.error-message.success .error-icon {
    background-color: #28a745;
}

.error-message.success .error-close {
    color: #155724;
}

/* Responsive Design */
@media (max-width: 1024px) {
    .main-content {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .compact-header {
        flex-direction: column;
        align-items: stretch;
    }

    .header-left {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--spacing-sm);
    }

    .header-right {
        flex-direction: column;
    }

    .username-input {
        width: 100%;
    }

    .filters-row {
        flex-direction: column;
        align-items: stretch;
    }

    .filter-group-inline {
        flex-wrap: wrap;
    }

    .filter-actions {
        margin-left: 0;
        flex-direction: column;
    }

    .btn-compact {
        width: 100%;
    }

    .stats-bar-compact {
        flex-wrap: wrap;
        justify-content: center;
    }

    #problem-table {
        font-size: 0.8rem;
    }

    #problem-table th,
    #problem-table td {
        padding: var(--spacing-sm);
    }
}

/* Hide Tags Column */
#problem-table th:nth-child(4),
#problem-table td:nth-child(4) {
    display: none;
}

/* Empty State */
.empty-state {
    text-align: center;
    padding: var(--spacing-xl);
    color: var(--text-secondary);
}

.empty-state h3 {
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
}

.empty-state p {
    margin-bottom: var(--spacing-md);
}