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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    padding: 20px;
}

.container {
    max-width: 1400px;
    margin: 0 auto;
    background: white;
    border-radius: 20px;
    padding: 40px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
}

h1 {
    color: #333;
    text-align: center;
    margin-bottom: 10px;
    font-size: 2.5em;
}

.subtitle {
    text-align: center;
    color: #666;
    margin-bottom: 30px;
    font-size: 1.1em;
}

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

.upload-area {
    border: 3px dashed #667eea;
    border-radius: 15px;
    padding: 60px;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s ease;
    background: #f8f9ff;
}

.upload-area:hover {
    border-color: #764ba2;
    background: #f0f2ff;
    transform: translateY(-2px);
}

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

.upload-content svg {
    color: #667eea;
    margin-bottom: 15px;
}

.upload-content p {
    color: #333;
    font-size: 1.2em;
    margin: 10px 0;
}

.upload-hint {
    color: #999;
    font-size: 0.9em;
}

.controls-section {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
    margin-bottom: 30px;
    padding: 25px;
    background: #f8f9ff;
    border-radius: 15px;
}

.control-group {
    display: flex;
    align-items: center;
    gap: 10px;
}

.control-group label {
    color: #333;
    font-weight: 500;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 8px;
}

.control-group input[type="number"] {
    padding: 8px 12px;
    border: 2px solid #ddd;
    border-radius: 8px;
    font-size: 1em;
    width: 100px;
}

.control-group input[type="checkbox"] {
    width: 20px;
    height: 20px;
    cursor: pointer;
}

.generate-btn, .download-btn {
    grid-column: 1 / -1;
    padding: 15px 40px;
    font-size: 1.2em;
    font-weight: bold;
    color: white;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border: none;
    border-radius: 10px;
    cursor: pointer;
    transition: all 0.3s ease;
    margin-top: 10px;
}

.generate-btn:hover:not(:disabled), .download-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 25px rgba(102, 126, 234, 0.4);
}

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

.preview-section {
    margin-top: 40px;
}

.preview-section h2 {
    color: #333;
    margin-bottom: 20px;
}

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

.preview-item {
    position: relative;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease;
}

.preview-item:hover {
    transform: scale(1.05);
}

.preview-item img {
    width: 100%;
    height: auto;
    display: block;
}

.preview-item .download-icon {
    position: absolute;
    top: 10px;
    right: 10px;
    background: rgba(102, 126, 234, 0.9);
    color: 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;
}

.preview-item .download-icon:hover {
    background: rgba(118, 75, 162, 0.9);
    transform: scale(1.1);
}

.loading {
    text-align: center;
    padding: 40px;
}

.spinner {
    border: 4px solid #f3f3f3;
    border-top: 4px solid #667eea;
    border-radius: 50%;
    width: 50px;
    height: 50px;
    animation: spin 1s linear infinite;
    margin: 0 auto 20px;
}

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

.loading p {
    color: #666;
    font-size: 1.1em;
}