* {
    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;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    min-height: calc(100vh - 40px);
}

.upload-card {
    background: white;
    border-radius: 12px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    padding: 40px;
    flex-grow: 1;
    display: flex;
    flex-direction: column;
}

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

.header h1 {
    color: #2d3748;
    font-size: 2.5rem;
    margin-bottom: 10px;
    font-weight: 700;
}

.header p {
    color: #718096;
    font-size: 1.1rem;
}

.upload-section {
    margin-bottom: 30px;
}

.drop-zone {
    border: 3px dashed #cbd5e0;
    border-radius: 12px;
    padding: 60px 20px;
    text-align: center;
    transition: all 0.3s ease;
    cursor: pointer;
    background: #f7fafc;
}

.drop-zone:hover {
    border-color: #667eea;
    background: #edf2f7;
}

.drop-zone.drag-over {
    border-color: #667eea;
    background: #ebf8ff;
    transform: scale(1.02);
}

.drop-content svg {
    color: #a0aec0;
    margin-bottom: 20px;
}

.drop-content h3 {
    color: #2d3748;
    font-size: 1.5rem;
    margin-bottom: 10px;
    font-weight: 600;
}

.drop-content p {
    color: #718096;
    margin-bottom: 5px;
}

.upload-btn {
    width: 100%;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    border-radius: 8px;
    padding: 16px 24px;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    margin-top: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
}

.upload-btn:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(102, 126, 234, 0.4);
}

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

.btn-spinner {
    animation: spin 1s linear infinite;
}

@keyframes spin {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

.file-list {
    background: #f7fafc;
    border-radius: 8px;
    padding: 20px;
    margin-bottom: 20px;
}

.file-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 12px 0;
    border-bottom: 1px solid #e2e8f0;
}

.file-item:last-child {
    border-bottom: none;
}

.file-info {
    display: flex;
    align-items: center;
    gap: 12px;
}

.file-icon {
    width: 24px;
    height: 24px;
    color: #667eea;
}

.file-details h4 {
    color: #2d3748;
    font-size: 0.9rem;
    font-weight: 600;
}

.file-details p {
    color: #718096;
    font-size: 0.8rem;
}

.remove-btn {
    background: #fed7d7;
    color: #c53030;
    border: none;
    border-radius: 4px;
    padding: 6px 12px;
    font-size: 0.8rem;
    cursor: pointer;
    transition: background-color 0.2s;
}

.remove-btn:hover {
    background: #feb2b2;
}

.progress-section {
    margin-bottom: 20px;
}

.progress-bar {
    width: 100%;
    height: 8px;
    background: #e2e8f0;
    border-radius: 4px;
    overflow: hidden;
    margin-bottom: 10px;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    width: 0%;
    transition: width 0.3s ease;
}

.progress-text {
    text-align: center;
    color: #718096;
    font-size: 0.9rem;
}

.results {
    background: #f0fff4;
    border: 1px solid #9ae6b4;
    border-radius: 8px;
    padding: 20px;
    margin-top: 20px;
}

.results.error {
    background: #fed7d7;
    border-color: #feb2b2;
}

.results h3 {
    color: #22543d;
    margin-bottom: 15px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.results.error h3 {
    color: #c53030;
}

.result-item {
    background: white;
    border-radius: 6px;
    padding: 12px;
    margin-bottom: 8px;
    border-left: 4px solid #48bb78;
}

.result-item.error {
    border-left-color: #e53e3e;
}

.result-item h4 {
    color: #2d3748;
    font-size: 0.9rem;
    margin-bottom: 4px;
}

.result-item p {
    color: #718096;
    font-size: 0.8rem;
}

.footer {
    text-align: center;
    margin-top: 40px;
    padding: 20px;
    color: white;
    opacity: 0.8;
}

.footer p {
    margin-bottom: 8px;
    font-size: 0.9rem;
}

/* Responsive design */
@media (max-width: 640px) {
    body {
        padding: 10px;
    }
    
    .upload-card {
        padding: 20px;
    }
    
    .header h1 {
        font-size: 2rem;
    }
    
    .drop-zone {
        padding: 40px 20px;
    }
    
    .drop-content h3 {
        font-size: 1.2rem;
    }
}

/* Animation for successful upload */
.success-animation {
    animation: successPulse 0.6s ease-out;
}

@keyframes successPulse {
    0% { transform: scale(1); }
    50% { transform: scale(1.05); }
    100% { transform: scale(1); }
}