:root {
            --primary: #206BC4;
            --primary-hover: #1a56a0;
            --bg-body: #f4f7fb;
            --bg-card: #ffffff;
            --text-main: #2d3748;
            --text-muted: #718096;
            --border: #e2e8f0;
            --radius: 8px;
            --shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
            --transition: all 0.2s ease;
        }

        * { box-sizing: border-box; font-family: 'Segoe UI', Roboto, Helvetica, Arial, sans-serif; }
        body { background-color: var(--bg-body); color: var(--text-main); line-height: 1.6; }

        /* Upload Zone */
        .upload-area {
            background: var(--bg-card);
            border: 2px dashed var(--border);
            border-radius: var(--radius);
            padding: 40px;
            text-align: center;
            cursor: pointer;
            transition: var(--transition);
            margin: 1.5rem;
        }
        .upload-area:hover, .upload-area.drag-over { border-color: var(--primary); background: #f0f7ff; }
        .upload-area svg { width: 64px; height: 64px; fill: var(--primary); margin-bottom: 1rem; }
        .upload-area p { font-size: 1.1rem; font-weight: 500; }
        .upload-area span { color: var(--text-muted); font-size: 0.9rem; }
        #fileInput { display: none; }

        /* Main Workspace */
        .workspace { display: grid; grid-template-columns: 1fr 350px; gap: 0.5rem; display: none; }
        @media (max-width: 992px) { .workspace { grid-template-columns: 1fr; } }

        /* Preview Section */
        .preview-card { background: var(--bg-card); border-radius: var(--radius); padding: 20px; box-shadow: var(--shadow); }
        .preview-container { 
            width: 100%; min-height: 300px; max-height: 500px; 
            background: #f1f1f1; border-radius: 4px; display: flex; 
            align-items: center; justify-content: center; overflow: hidden;
            background-image: linear-gradient(45deg, #eee 25%, transparent 25%), linear-gradient(-45deg, #eee 25%, transparent 25%), linear-gradient(45deg, transparent 75%, #eee 75%), linear-gradient(-45deg, transparent 75%, #eee 75%);
            background-size: 20px 20px; background-position: 0 0, 0 10px, 10px -10px, -10px 0px;
        }
        .preview-container img { max-width: 100%; max-height: 100%; object-fit: contain; }
        
        /* Bulk List */
        .bulk-list { margin-top: 20px; border-top: 1px solid var(--border); padding-top: 15px; }
        .bulk-item { display: flex; align-items: center; gap: 10px; padding: 8px; border-bottom: 1px solid #f8f8f8; font-size: 0.85rem; }
        .bulk-item img { width: 40px; height: 40px; object-fit: cover; border-radius: 4px; }

        /* Controls Section */
        .controls-card { background: var(--bg-card); border-radius: var(--radius); padding: 25px; box-shadow: var(--shadow); height: fit-content; }
        .control-group { margin-bottom: 1.5rem; }
        .control-label { display: block; font-weight: 600; margin-bottom: 8px; font-size: 0.9rem; color: var(--text-main); }
        
        .input-row { display: flex; gap: 10px; align-items: center; }
        input[type="number"], input[type="text"], select {
            width: 100%; padding: 10px; border: 1px solid var(--border); border-radius: 6px; outline: none; transition: var(--transition);
        }
        input:focus, select:focus { border-color: var(--primary); }
        
        .checkbox-group { display: flex; align-items: center; gap: 8px; font-size: 0.85rem; cursor: pointer; }
        
        .quality-slider { width: 100%; height: 6px; background: var(--border); border-radius: 5px; appearance: none; outline: none; }
        .quality-slider::-webkit-slider-thumb { appearance: none; width: 18px; height: 18px; background: var(--primary); border-radius: 50%; cursor: pointer; }

        .btn {
            width: 100%; padding: 12px; border: none; border-radius: 6px; font-weight: 600; cursor: pointer;
            transition: var(--transition); display: flex; align-items: center; justify-content: center; gap: 8px;
        }
        .btn-primary { background: var(--primary); color: white; margin-bottom: 10px; }
        .btn-primary:hover { background: var(--primary-hover); }
        .btn-outline { background: transparent; border: 1px solid var(--border); color: var(--text-muted); }
        .btn-outline:hover { background: #f8fafc; color: var(--text-main); }

        /* Presets Grid */
        .presets-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 8px; margin-top: 5px; }
        .preset-btn { 
            padding: 6px; font-size: 0.75rem; border: 1px solid var(--border); border-radius: 4px; 
            background: #fff; cursor: pointer; text-align: center; 
        }
        .preset-btn:hover { border-color: var(--primary); color: var(--primary); }

        /* SEO Section */
        .seo-content { margin-top: 4rem; background: var(--bg-card); padding: 40px; border-radius: var(--radius); box-shadow: var(--shadow); }
        .seo-content h2 { margin-bottom: 20px; color: var(--primary); }
        .seo-content h3 { margin: 20px 0 10px; }
        .seo-content p { color: var(--text-muted); margin-bottom: 15px; }

        .hidden { display: none !important; }
        .loader { border: 3px solid #f3f3f3; border-top: 3px solid var(--primary); border-radius: 50%; width: 20px; height: 20px; animation: spin 1s linear infinite; display: none; }
        @keyframes spin { 0% { transform: rotate(0deg); } 100% { transform: rotate(360deg); } }