Create a premium luxury ecommerce Product Gallery system inspired by Zara, Farfetch, Apple, Nike, and Shopify.

Requirements:

Desktop Layout:
- Left side vertical thumbnail gallery.
- Show maximum 5 thumbnails initially.
- If total images exceed 5, hide remaining thumbnails.
- Display a Chevron Down button below thumbnails.
- Clicking Chevron Down smoothly reveals additional hidden thumbnails.
- Change icon to Chevron Up when expanded.
- Clicking Chevron Up collapses gallery back to first 5 thumbnails.
- Smooth slide animation required.

Thumbnail Features:
- Active thumbnail should have a premium gold border.
- Hover effect with subtle zoom.
- Smooth transition animations.
- Lazy loading for performance.