* {
            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: 40px 20px;
        }
        .container {
            max-width: 800px;
            margin: 0 auto;
            background: white;
            border-radius: 20px;
            padding: 40px;
            box-shadow: 0 20px 60px rgba(0,0,0,0.3);
        }
        h1 {
            text-align: center;
            color: #333;
            margin-bottom: 30px;
            font-size: 2em;
        }
        .upload-area {
            border: 3px dashed #e0e0e0;
            border-radius: 12px;
            padding: 60px 20px;
            text-align: center;
            cursor: pointer;
            transition: all 0.3s;
            margin-bottom: 30px;
        }
        .upload-area:hover {
            border-color: #667eea;
            background: #f9f9f9;
        }
        .upload-area.dragover {
            border-color: #667eea;
            background: #e7f3ff;
        }
        .upload-icon {
            font-size: 4em;
            margin-bottom: 15px;
        }
        input[type="file"] {
            display: none;
        }
        .quality-control {
            margin: 30px 0;
        }
        .slider-container {
            display: flex;
            gap: 15px;
            align-items: center;
            margin-top: 10px;
        }
        input[type="range"] {
            flex: 1;
            height: 8px;
        }
        .value-display {
            min-width: 50px;
            text-align: right;
            font-family: 'Courier New', monospace;
            font-weight: bold;
            color: #667eea;
            font-size: 1.2em;
        }
        .preview-container {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 20px;
            margin: 30px 0;
        }
        .preview-box {
            border: 2px solid #e0e0e0;
            border-radius: 12px;
            padding: 20px;
            text-align: center;
        }
        .preview-box h3 {
            margin-bottom: 15px;
            color: #666;
        }
        .preview-box img {
            max-width: 100%;
            border-radius: 8px;
            margin-bottom: 15px;
        }
        .file-info {
            background: #f9f9f9;
            padding: 10px;
            border-radius: 8px;
            font-size: 0.9em;
            color: #666;
        }
        button {
            width: 100%;
            padding: 14px;
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            color: white;
            border: none;
            border-radius: 8px;
            font-size: 16px;
            font-weight: 600;
            cursor: pointer;
            transition: transform 0.2s;
            margin-bottom: 10px;
        }
        button:hover {
            transform: translateY(-2px);
        }
        button:disabled {
            opacity: 0.5;
            cursor: not-allowed;
        }
        button.secondary {
            background: linear-gradient(135deg, #95a5a6 0%, #7f8c8d 100%);
        }
        .hidden {
            display: none;
        }
        @media (max-width: 768px) {
            .preview-container {
                grid-template-columns: 1fr;
            }
        }