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

:root {
    --primary-color: #2563eb;
    --primary-hover: #1d4ed8;
    --secondary-color: #64748b;
    --success-color: #059669;
    --warning-color: #d97706;
    --error-color: #dc2626;
    --background-color: #f8fafc;
    --surface-color: #ffffff;
    --border-color: #e2e8f0;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --text-muted: #94a3b8;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    --border-radius: 8px;
    --border-radius-sm: 4px;
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    line-height: 1.5;
    color: var(--text-primary);
    background-color: var(--background-color);
}

/* Layout */
.app-container {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.app-header {
    background: var(--surface-color);
    border-bottom: 1px solid var(--border-color);
    padding: var(--spacing-lg);
    display: flex;
    justify-content: space-between;
    align-items: center;
    box-shadow: var(--shadow-sm);
}

.app-header h1 {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-primary);
}

.file-controls {
    display: flex;
    gap: var(--spacing-md);
    align-items: center;
}

.app-main {
    flex: 1;
    padding: var(--spacing-lg);
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
}

/* Video Section */
.video-section {
    background: var(--surface-color);
    border-radius: var(--border-radius);
    padding: var(--spacing-lg);
    box-shadow: var(--shadow-md);
}

.video-container {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

#video-player {
    width: 100%;
    max-height: 60vh;
    border-radius: var(--border-radius);
    background: #000;
}

.video-info {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-sm) 0;
    border-top: 1px solid var(--border-color);
    margin-top: var(--spacing-sm);
}

.current-frame-info {
    display: flex;
    gap: var(--spacing-lg);
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.current-frame-info span {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.video-controls-extended {
    display: flex;
    gap: var(--spacing-sm);
    align-items: center;
}

.frame-slider {
    width: 200px;
    height: 4px;
    border-radius: 2px;
    background: var(--border-color);
    outline: none;
    appearance: none;
}

.frame-slider::-webkit-slider-thumb {
    appearance: none;
    width: 16px;
    height: 16px;
    border-radius: 50%;
    background: var(--primary-color);
    cursor: pointer;
}

.frame-slider::-moz-range-thumb {
    width: 16px;
    height: 16px;
    border-radius: 50%;
    background: var(--primary-color);
    cursor: pointer;
    border: none;
}

/* Analysis Container */
.analysis-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-lg);
}

.analysis-panel {
    background: var(--surface-color);
    border-radius: var(--border-radius);
    padding: var(--spacing-lg);
    box-shadow: var(--shadow-md);
}

.analysis-panel h2 {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
}

.chart-container {
    position: relative;
    height: 300px;
    margin-bottom: var(--spacing-md);
}

.chart-controls {
    display: flex;
    gap: var(--spacing-sm);
    justify-content: center;
}

/* Metadata Panel */
.metadata-panel {
    grid-column: 1 / -1;
}

.metadata-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-lg);
}

.metadata-basic h3,
.metadata-tracks h3 {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
}

.metadata-basic dl {
    display: grid;
    grid-template-columns: auto 1fr;
    gap: var(--spacing-xs) var(--spacing-md);
}

.metadata-basic dt {
    font-weight: 500;
    color: var(--text-secondary);
}

.metadata-basic dd {
    color: var(--text-primary);
}

/* Box Panel */
.box-panel {
    grid-column: 1 / -1;
}

.box-tree-container {
    max-height: 400px;
    overflow-y: auto;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-sm);
    padding: var(--spacing-sm);
}

/* Button Styles */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-sm) var(--spacing-md);
    border: 1px solid transparent;
    border-radius: var(--border-radius-sm);
    font-size: 0.875rem;
    font-weight: 500;
    text-decoration: none;
    cursor: pointer;
    transition: all 0.2s ease;
    background: var(--primary-color);
    color: white;
}

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

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

.btn-secondary {
    background: var(--surface-color);
    color: var(--text-primary);
    border-color: var(--border-color);
}

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

.btn-small {
    padding: var(--spacing-xs) var(--spacing-sm);
    font-size: 0.75rem;
}

/* File Input */
#video-file-input {
    display: none;
}

.file-input-label {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-sm) var(--spacing-md);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-sm);
    font-size: 0.875rem;
    font-weight: 500;
    text-decoration: none;
    cursor: pointer;
    transition: all 0.2s ease;
    background: var(--surface-color);
    color: var(--text-primary);
}

.file-input-label:hover {
    background: var(--background-color);
}

/* Utility Classes */
.hidden {
    display: none !important;
}

.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.8);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
}

.loading-content {
    background: var(--surface-color);
    padding: var(--spacing-xl);
    border-radius: var(--border-radius);
    text-align: center;
    min-width: 200px;
}

.spinner {
    width: 32px;
    height: 32px;
    border: 3px solid var(--border-color);
    border-top: 3px solid var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto var(--spacing-md);
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.modal {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
}

.modal-content {
    background: var(--surface-color);
    padding: var(--spacing-xl);
    border-radius: var(--border-radius);
    min-width: 300px;
    max-width: 500px;
}

.modal-content h3 {
    margin-bottom: var(--spacing-md);
    color: var(--error-color);
}

.modal-content p {
    margin-bottom: var(--spacing-lg);
    color: var(--text-secondary);
}

/* Responsive Design */
@media (max-width: 1024px) {
    .analysis-container {
        grid-template-columns: 1fr;
    }
    
    .metadata-content {
        grid-template-columns: 1fr;
    }
    
    .app-header {
        flex-direction: column;
        gap: var(--spacing-md);
        align-items: stretch;
    }
    
    .file-controls {
        justify-content: center;
    }
}

@media (max-width: 768px) {
    .app-main {
        padding: var(--spacing-md);
    }
    
    .video-info {
        flex-direction: column;
        gap: var(--spacing-md);
        align-items: stretch;
    }
    
    .video-controls-extended {
        justify-content: center;
    }
    
    .frame-slider {
        width: 100%;
    }
}