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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    min-height: 100vh;
    color: #333;
    line-height: 1.6;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.header {
    text-align: center;
    margin-bottom: 30px;
    color: white;
}

.header h1 {
    font-size: 2.5rem;
    margin-bottom: 10px;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
}

.header p {
    font-size: 1.2rem;
    opacity: 0.9;
}

.main-content {
    flex: 1;
    background: white;
    border-radius: 15px;
    padding: 30px;
    position: relative;
}

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

.upload-area {
    border: 3px dashed #667eea;
    border-radius: 15px;
    padding: 50px 20px;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s ease;
    background: #f8f9ff;
}

.upload-area:hover {
    border-color: #5a67d8;
    background: #f0f4ff;
    transform: translateY(-2px);
}

.upload-area.dragover {
    border-color: #4c51bf;
    background: #e6fffa;
    transform: scale(1.02);
}

.upload-content {
    pointer-events: none;
}

.upload-icon {
    font-size: 3rem;
    color: #667eea;
    margin-bottom: 20px;
}

.upload-content h3 {
    font-size: 1.5rem;
    margin-bottom: 10px;
    color: #4a5568;
}

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

.supported-formats {
    font-size: 0.9rem;
    color: #a0aec0;
    font-style: italic;
}

.error-message {
    display: none;
    background: #fed7d7;
    color: #c53030;
    padding: 15px;
    border-radius: 10px;
    margin-bottom: 20px;
    border-left: 4px solid #e53e3e;
}

.success-message {
    display: none;
    background: #c6f6d5;
    color: #22543d;
    padding: 15px;
    border-radius: 10px;
    margin-bottom: 20px;
    border-left: 4px solid #38a169;
}

.preview-section {
    display: none;
    margin-bottom: 30px;
}

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

.section-header h2 {
    font-size: 1.8rem;
    color: #2d3748;
    margin-bottom: 5px;
}

.drag-instruction {
    color: #718096;
    font-size: 0.9rem;
}

.image-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 20px;
    margin-bottom: 30px;
}

.image-item {
    position: relative;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
    cursor: move;
    transition: all 0.3s ease;
    background: white;
}

.image-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(0,0,0,0.15);
}

.image-item.dragging {
    opacity: 0.5;
    transform: rotate(5deg);
}

.image-item img {
    width: 100%;
    height: 150px;
    object-fit: cover;
    display: block;
}

.image-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0,0,0,0.7);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transition: opacity 0.3s ease;
}

.image-item:hover .image-overlay {
    opacity: 1;
}

.image-controls {
    display: flex;
    gap: 10px;
}

.control-btn {
    background: white;
    border: none;
    border-radius: 50%;
    width: 40px;
    height: 40px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s ease;
    color: #333;
}

.control-btn:hover {
    background: #f7fafc;
    transform: scale(1.1);
}

.control-btn.delete {
    background: #e53e3e;
    color: white;
}

.control-btn.delete:hover {
    background: #c53030;
}

.image-info {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    background: linear-gradient(transparent, rgba(0,0,0,0.8));
    color: white;
    padding: 10px;
    font-size: 0.8rem;
}

.action-buttons {
    display: none;
    justify-content: center;
    gap: 20px;
    margin-top: 30px;
}

.btn {
    padding: 15px 30px;
    border: none;
    border-radius: 10px;
    cursor: pointer;
    font-size: 1rem;
    font-weight: 600;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    gap: 8px;
    text-decoration: none;
}

.btn-primary {
    background: #667eea;
    color: white;
}

.btn-primary:hover {
    background: #5a67d8;
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(102, 126, 234, 0.4);
}

.btn-clear {
    background: #e2e8f0;
    color: #4a5568;
}

.btn-clear:hover {
    background: #cbd5e0;
    transform: translateY(-2px);
}

.loading-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(255,255,255,0.9);
    display: none;
    align-items: center;
    justify-content: center;
    border-radius: 15px;
    z-index: 1000;
}

.loading-content {
    text-align: center;
    color: #4a5568;
}

.spinner {
    width: 50px;
    height: 50px;
    border: 4px solid #e2e8f0;
    border-top: 4px solid #667eea;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto 20px;
}

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

.footer {
    text-align: center;
    margin-top: 30px;
    color: rgba(255,255,255,0.8);
    font-size: 0.9rem;
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 10px;
    }
    
    .header h1 {
        font-size: 2rem;
    }
    
    .main-content {
        padding: 20px;
    }
    
    .upload-area {
        padding: 30px 15px;
    }
    
    .upload-icon {
        font-size: 2rem;
    }
    
    .upload-content h3 {
        font-size: 1.2rem;
    }
    
    .image-grid {
        grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
        gap: 15px;
    }
    
    .image-item img {
        height: 120px;
    }
    
    .action-buttons {
        flex-direction: column;
        align-items: center;
    }
    
    .btn {
        width: 100%;
        max-width: 250px;
        justify-content: center;
    }
}

@media (max-width: 480px) {
    .header h1 {
        font-size: 1.5rem;
    }
    
    .header p {
        font-size: 1rem;
    }
    
    .main-content {
        padding: 15px;
    }
    
    .image-grid {
        grid-template-columns: repeat(auto-fill, minmax(120px, 1fr));
        gap: 10px;
    }
    
    .image-item img {
        height: 100px;
    }
    
    .control-btn {
        width: 35px;
        height: 35px;
    }
}

/* Drag and Drop Styles */
.drag-over {
    background: #e6fffa;
    border-color: #4c51bf;
}

.drop-zone {
    border: 2px dashed #667eea;
    border-radius: 10px;
    padding: 20px;
    margin: 10px 0;
    background: #f8f9ff;
    transition: all 0.3s ease;
}

.drop-zone.active {
    border-color: #4c51bf;
    background: #e6fffa;
}

/* Animation for image items */
.image-item {
    animation: fadeInUp 0.5s ease-out;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}