frontend/styles.css

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    padding: 20px;
    color: #333;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
}

header {
    text-align: center;
    color: white;
    margin-bottom: 40px;
}

header h1 {
    font-size: 2.5rem;
    margin-bottom: 10px;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.2);
}

header p {
    font-size: 1.1rem;
    opacity: 0.9;
}

.upload-section {
    background: white;
    border-radius: 16px;
    padding: 30px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.2);
    margin-bottom: 30px;
}

.upload-box {
    border: 3px dashed #667eea;
    border-radius: 12px;
    padding: 60px 20px;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s ease;
    background: #f8f9ff;
}

.upload-box:hover {
    background: #f0f2ff;
    border-color: #764ba2;
}

.upload-box.dragover {
    background: #e8ebff;
    border-color: #764ba2;
    transform: scale(1.02);
}

.upload-content svg {
    color: #667eea;
    margin-bottom: 20px;
}

.upload-content h3 {
    font-size: 1.3rem;
    margin-bottom: 10px;
    color: #333;
}

.upload-content p {
    color: #666;
    font-size: 0.9rem;
}

.btn {
    padding: 12px 30px;
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.3s ease;
    font-weight: 600;
    margin: 10px 5px;
}

.btn.primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    width: 100%;
    margin-top: 20px;
}

.btn.primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(102, 126, 234, 0.4);
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
}

.loading-section {
    background: white;
    border-radius: 16px;
    padding: 60px;
    text-align: center;
    box-shadow: 0 10px 30px rgba(0,0,0,0.2);
}

.spinner {
    width: 50px;
    height: 50px;
    border: 5px solid #f3f3f3;
    border-top: 5px solid #667eea;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto 20px;
}

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

.results-section {
    background: white;
    border-radius: 16px;
    padding: 30px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.2);
}

.stats-panel {
    margin-bottom: 30px;
    padding: 20px;
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    border-radius: 12px;
}

.stats-panel h3 {
    margin-bottom: 20px;
    color: #333;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 15px;
}

.stat-item {
    background: white;
    padding: 15px;
    border-radius: 8px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

.stat-label {
    font-weight: 600;
    color: #666;
}

.stat-value {
    font-size: 1.5rem;
    font-weight: bold;
    color: #667eea;
}

.visualization-panel h3 {
    margin-bottom: 15px;
    color: #333;
}

.controls {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 20px;
    padding: 15px;
    background: #f8f9fa;
    border-radius: 8px;
}

.controls label {
    display: flex;
    align-items: center;
    gap: 8px;
    cursor: pointer;
    margin-left: auto;
}

.controls input[type="checkbox"] {
    width: 18px;
    height: 18px;
    cursor: pointer;
}

#canvas3d {
    width: 100%;
    height: 600px;
    border-radius: 12px;
    background: linear-gradient(135deg, #1e3c72 0%, #2a5298 100%);
    overflow: hidden;
}

footer {
    text-align: center;
    color: white;
    margin-top: 40px;
    opacity: 0.8;
}

@media (max-width: 768px) {
    header h1 {
        font-size: 2rem;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
    }
    
    #canvas3d {
        height: 400px;
    }
}