/* Knowledge Graph Page Styles */

/* Main Layout */
.kg-container {
    display: flex;
    flex-direction: column;
    height: calc(100vh - 60px);
    gap: 0;
}

/* Controls Bar */
.kg-controls {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    padding: 16px 20px;
    background: var(--bg-card);
    border-bottom: 1px solid var(--border);
    align-items: center;
}

.kg-view-toggle {
    display: flex;
    background: var(--bg-primary);
    border-radius: var(--radius-sm);
    padding: 4px;
    gap: 4px;
}

.kg-view-btn {
    padding: 8px 16px;
    border: none;
    background: transparent;
    color: var(--text-secondary);
    border-radius: var(--radius-sm);
    cursor: pointer;
    font-size: 0.9rem;
    font-weight: 500;
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    gap: 6px;
}

.kg-view-btn:hover {
    color: var(--primary);
}

.kg-view-btn.active {
    background: var(--primary);
    color: white;
    box-shadow: var(--shadow);
}

.kg-filters {
    display: flex;
    gap: 10px;
    flex: 1;
    flex-wrap: wrap;
}

.kg-filter-select,
.kg-search-input {
    padding: 8px 14px;
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    background: var(--bg-secondary);
    color: var(--text-primary);
    font-size: 0.9rem;
    min-width: 140px;
}

.kg-search-input {
    flex: 1;
    min-width: 200px;
    max-width: 300px;
}

.kg-search-input:focus,
.kg-filter-select:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(34, 197, 94, 0.1);
}

.kg-generate-btn {
    padding: 8px 16px;
    background: linear-gradient(135deg, var(--accent-secondary), var(--primary));
    color: white;
    border: none;
    border-radius: var(--radius-sm);
    cursor: pointer;
    font-size: 0.9rem;
    font-weight: 500;
    display: flex;
    align-items: center;
    gap: 6px;
    transition: all 0.2s ease;
}

.kg-generate-btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-glow);
}

/* Main Content Area */
.kg-main {
    flex: 1;
    display: flex;
    position: relative;
    overflow: hidden;
    background: linear-gradient(135deg, #0f172a 0%, #1e293b 50%, #0f172a 100%);
}

/* Graph Container */
.kg-graph-container {
    flex: 1;
    position: relative;
    overflow: hidden;
}

#kg-graph {
    width: 100%;
    height: 100%;
    touch-action: none; /* Prevent default touch behaviors */
    -webkit-overflow-scrolling: touch;
}

#kg-graph svg {
    display: block;
    touch-action: none;
}

#kg-graph svg g {
    will-change: transform;
}

/* Timeline Container */
.kg-timeline-container {
    flex: 1;
    overflow-y: auto;
    padding: 30px;
    display: none;
}

.kg-timeline-container.active {
    display: block;
}

.kg-graph-container.hidden {
    display: none;
}

/* Timeline Styles */
.kg-timeline {
    position: relative;
    max-width: 1000px;
    margin: 0 auto;
    padding-left: 60px;
}

.kg-timeline::before {
    content: '';
    position: absolute;
    left: 30px;
    top: 0;
    bottom: 0;
    width: 4px;
    background: linear-gradient(to bottom, var(--primary), var(--accent-secondary));
    border-radius: 2px;
}

.kg-timeline-era {
    margin-bottom: 40px;
}

.kg-timeline-era-title {
    font-size: 1.4rem;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 20px;
    padding: 10px 20px;
    background: rgba(34, 197, 94, 0.1);
    border-radius: var(--radius-sm);
    display: inline-block;
}

.kg-timeline-item {
    position: relative;
    margin-bottom: 24px;
    padding-left: 40px;
}

.kg-timeline-item::before {
    content: '';
    position: absolute;
    left: -38px;
    top: 20px;
    width: 16px;
    height: 16px;
    background: var(--bg-card);
    border: 4px solid var(--primary);
    border-radius: 50%;
    z-index: 1;
}

.kg-timeline-item.scientist::before {
    border-color: #8b5cf6;
}

.kg-timeline-item.equation::before {
    border-color: #22c55e;
}

.kg-timeline-item.concept::before {
    border-color: #f59e0b;
}

.kg-timeline-item.discovery::before {
    border-color: #06b6d4;
}

.kg-timeline-card {
    background: var(--bg-card);
    border-radius: var(--radius-md);
    padding: 20px;
    box-shadow: var(--shadow);
    cursor: pointer;
    transition: all 0.3s ease;
    border-left: 4px solid var(--primary);
}

.kg-timeline-card:hover {
    transform: translateX(8px);
    box-shadow: var(--shadow-md);
}

.kg-timeline-card.scientist {
    border-left-color: #8b5cf6;
}

.kg-timeline-card.equation {
    border-left-color: #22c55e;
}

.kg-timeline-card.concept {
    border-left-color: #f59e0b;
}

.kg-timeline-card.discovery {
    border-left-color: #06b6d4;
}

.kg-timeline-year {
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-bottom: 6px;
}

.kg-timeline-name {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 4px;
}

.kg-timeline-name-zh {
    font-size: 0.95rem;
    color: var(--text-secondary);
    margin-bottom: 8px;
}

.kg-timeline-desc {
    font-size: 0.9rem;
    color: var(--text-secondary);
    line-height: 1.5;
}

.kg-timeline-formula {
    font-family: 'Times New Roman', serif;
    font-size: 1.2rem;
    color: var(--primary);
    background: var(--bg-primary);
    padding: 8px 12px;
    border-radius: var(--radius-sm);
    margin-top: 10px;
    display: inline-block;
}

.kg-timeline-type-badge {
    display: inline-block;
    padding: 2px 10px;
    border-radius: 12px;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    margin-bottom: 8px;
}

.kg-timeline-type-badge.scientist {
    background: rgba(139, 92, 246, 0.15);
    color: #8b5cf6;
}

.kg-timeline-type-badge.equation {
    background: rgba(34, 197, 94, 0.15);
    color: #22c55e;
}

.kg-timeline-type-badge.concept {
    background: rgba(245, 158, 11, 0.15);
    color: #f59e0b;
}

.kg-timeline-type-badge.discovery {
    background: rgba(6, 182, 212, 0.15);
    color: #06b6d4;
}

/* Detail Panel */
.kg-detail-panel {
    width: 380px;
    background: var(--bg-card);
    border-left: 1px solid var(--border);
    padding: 24px;
    overflow-y: auto;
    transform: translateX(100%);
    transition: transform 0.3s ease;
    position: absolute;
    right: 0;
    top: 0;
    bottom: 0;
    z-index: 100;
}

.kg-detail-panel.open {
    transform: translateX(0);
}

.kg-detail-close {
    position: absolute;
    top: 16px;
    right: 16px;
    width: 32px;
    height: 32px;
    border: none;
    background: var(--bg-primary);
    border-radius: 50%;
    cursor: pointer;
    color: var(--text-secondary);
    font-size: 1.2rem;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s ease;
}

.kg-detail-close:hover {
    background: var(--danger);
    color: white;
}

.kg-detail-type {
    display: inline-block;
    padding: 4px 12px;
    border-radius: 16px;
    font-size: 0.8rem;
    font-weight: 600;
    text-transform: uppercase;
    margin-bottom: 12px;
}

.kg-detail-type.scientist {
    background: rgba(139, 92, 246, 0.15);
    color: #8b5cf6;
}

.kg-detail-type.equation {
    background: rgba(34, 197, 94, 0.15);
    color: #22c55e;
}

.kg-detail-type.concept {
    background: rgba(245, 158, 11, 0.15);
    color: #f59e0b;
}

.kg-detail-type.discovery {
    background: rgba(6, 182, 212, 0.15);
    color: #06b6d4;
}

.kg-detail-name {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 4px;
}

.kg-detail-name-zh {
    font-size: 1.1rem;
    color: var(--text-secondary);
    margin-bottom: 16px;
}

.kg-detail-years {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 0.95rem;
    color: var(--text-muted);
    margin-bottom: 16px;
}

.kg-detail-years i {
    color: var(--primary);
}

.kg-detail-formula {
    font-family: 'Times New Roman', serif;
    font-size: 1.8rem;
    color: var(--primary);
    background: linear-gradient(135deg, var(--bg-primary), rgba(34, 197, 94, 0.1));
    padding: 16px 20px;
    border-radius: var(--radius-md);
    margin-bottom: 20px;
    text-align: center;
    border: 1px solid rgba(34, 197, 94, 0.2);
}

.kg-detail-section {
    margin-bottom: 20px;
}

.kg-detail-section-title {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 8px;
}

.kg-detail-description {
    font-size: 0.95rem;
    color: var(--text-primary);
    line-height: 1.6;
    margin-bottom: 8px;
}

.kg-detail-description-zh {
    font-size: 0.9rem;
    color: var(--text-secondary);
    line-height: 1.6;
}

.kg-detail-connections {
    margin-top: 24px;
}

.kg-connection-item {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 10px 12px;
    background: var(--bg-primary);
    border-radius: var(--radius-sm);
    margin-bottom: 8px;
    cursor: pointer;
    transition: all 0.2s ease;
}

.kg-connection-item:hover {
    background: rgba(34, 197, 94, 0.1);
    transform: translateX(4px);
}

.kg-connection-icon {
    width: 32px;
    height: 32px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.8rem;
    color: white;
}

.kg-connection-icon.scientist {
    background: #8b5cf6;
}

.kg-connection-icon.equation {
    background: #22c55e;
}

.kg-connection-icon.concept {
    background: #f59e0b;
}

.kg-connection-icon.discovery {
    background: #06b6d4;
}

.kg-connection-info {
    flex: 1;
}

.kg-connection-name {
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--text-primary);
}

.kg-connection-relation {
    font-size: 0.75rem;
    color: var(--text-muted);
}

/* Graph Node Styles (D3) */
.kg-node {
    cursor: pointer;
}

.kg-node circle {
    stroke: #fff;
    stroke-width: 2px;
    transition: all 0.2s ease;
}

.kg-node:hover circle {
    stroke-width: 4px;
    filter: drop-shadow(0 0 8px currentColor);
}

.kg-node text {
    font-size: 11px;
    fill: #fff;
    text-anchor: middle;
    pointer-events: none;
    text-shadow: 0 1px 3px rgba(0,0,0,0.8);
}

.kg-link {
    stroke: rgba(255, 255, 255, 0.2);
    stroke-width: 1.5px;
    fill: none;
}

.kg-link:hover {
    stroke: rgba(255, 255, 255, 0.5);
    stroke-width: 2.5px;
}

.kg-link-label {
    font-size: 9px;
    fill: rgba(255, 255, 255, 0.6);
    text-anchor: middle;
}

/* Stats Bar */
.kg-stats {
    display: flex;
    gap: 20px;
    padding: 12px 20px;
    background: var(--bg-card);
    border-top: 1px solid var(--border);
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.kg-stat-item {
    display: flex;
    align-items: center;
    gap: 6px;
}

.kg-stat-value {
    font-weight: 600;
    color: var(--text-primary);
}

.kg-stat-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
}

.kg-stat-dot.scientist {
    background: #8b5cf6;
}

.kg-stat-dot.equation {
    background: #22c55e;
}

.kg-stat-dot.concept {
    background: #f59e0b;
}

.kg-stat-dot.discovery {
    background: #06b6d4;
}

/* Loading State */
.kg-loading {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 100%;
    color: white;
    gap: 16px;
}

.kg-loading-spinner {
    width: 48px;
    height: 48px;
    border: 4px solid rgba(255, 255, 255, 0.2);
    border-top-color: var(--primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

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

/* Generate Modal */
.kg-modal {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.6);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
}

.kg-modal.open {
    opacity: 1;
    visibility: visible;
}

.kg-modal-content {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    padding: 32px;
    width: 90%;
    max-width: 500px;
    transform: translateY(20px);
    transition: transform 0.3s ease;
}

.kg-modal.open .kg-modal-content {
    transform: translateY(0);
}

.kg-modal-title {
    font-size: 1.4rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 8px;
}

.kg-modal-subtitle {
    font-size: 0.95rem;
    color: var(--text-secondary);
    margin-bottom: 24px;
}

.kg-modal-input {
    width: 100%;
    padding: 14px 16px;
    border: 2px solid var(--border);
    border-radius: var(--radius-md);
    font-size: 1rem;
    margin-bottom: 16px;
    transition: border-color 0.2s ease;
}

.kg-modal-input:focus {
    outline: none;
    border-color: var(--primary);
}

.kg-modal-type-select {
    display: flex;
    gap: 8px;
    margin-bottom: 24px;
}

.kg-modal-type-btn {
    flex: 1;
    padding: 10px;
    border: 2px solid var(--border);
    background: transparent;
    border-radius: var(--radius-sm);
    cursor: pointer;
    font-size: 0.85rem;
    color: var(--text-secondary);
    transition: all 0.2s ease;
}

.kg-modal-type-btn:hover {
    border-color: var(--primary);
}

.kg-modal-type-btn.active {
    background: var(--primary);
    border-color: var(--primary);
    color: white;
}

.kg-modal-actions {
    display: flex;
    gap: 12px;
    justify-content: flex-end;
}

.kg-modal-btn {
    padding: 12px 24px;
    border: none;
    border-radius: var(--radius-sm);
    font-size: 0.95rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s ease;
}

.kg-modal-btn.cancel {
    background: var(--bg-primary);
    color: var(--text-secondary);
}

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

.kg-modal-btn:hover {
    transform: translateY(-2px);
}

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

/* Empty State */
.kg-empty {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 100%;
    color: rgba(255, 255, 255, 0.6);
    text-align: center;
    padding: 40px;
}

.kg-empty i {
    font-size: 4rem;
    margin-bottom: 16px;
    opacity: 0.5;
}

.kg-empty h3 {
    font-size: 1.3rem;
    margin-bottom: 8px;
}

.kg-empty p {
    font-size: 0.95rem;
    opacity: 0.7;
}

/* Responsive */
@media (max-width: 768px) {
    .kg-controls {
        flex-direction: column;
        align-items: stretch;
    }

    .kg-view-toggle {
        justify-content: center;
    }

    .kg-filters {
        flex-direction: column;
    }

    .kg-search-input {
        max-width: none;
    }

    .kg-detail-panel {
        width: 100%;
    }

    .kg-timeline {
        padding-left: 40px;
    }

    .kg-timeline::before {
        left: 15px;
    }

    .kg-timeline-item::before {
        left: -33px;
    }

    .kg-stats {
        flex-wrap: wrap;
        gap: 12px;
    }
}

/* Tooltip */
.kg-tooltip {
    position: absolute;
    background: var(--bg-dark);
    color: white;
    padding: 8px 12px;
    border-radius: var(--radius-sm);
    font-size: 0.85rem;
    pointer-events: none;
    z-index: 1000;
    opacity: 0;
    transition: opacity 0.2s ease;
    max-width: 250px;
}

.kg-tooltip.visible {
    opacity: 1;
}

/* Legend */
.kg-legend {
    position: absolute;
    bottom: 20px;
    left: 20px;
    background: rgba(15, 23, 42, 0.9);
    border-radius: var(--radius-md);
    padding: 16px;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.kg-legend-item {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 0.85rem;
    color: rgba(255, 255, 255, 0.8);
}

.kg-legend-dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
}

.kg-legend-dot.scientist {
    background: #8b5cf6;
}

.kg-legend-dot.equation {
    background: #22c55e;
}

.kg-legend-dot.concept {
    background: #f59e0b;
}

.kg-legend-dot.discovery {
    background: #06b6d4;
}

/* Zoom Controls */
.kg-zoom-controls {
    position: absolute;
    bottom: 20px;
    right: 20px;
    display: flex;
    flex-direction: column;
    gap: 4px;
    background: rgba(15, 23, 42, 0.9);
    border-radius: var(--radius-sm);
    padding: 4px;
}

.kg-zoom-btn {
    width: 36px;
    height: 36px;
    border: none;
    background: transparent;
    color: white;
    font-size: 1.2rem;
    cursor: pointer;
    border-radius: var(--radius-sm);
    transition: background 0.2s ease;
}

.kg-zoom-btn:hover {
    background: rgba(255, 255, 255, 0.1);
}