Magento 2.4: Why is there a semi-transparent overlay at each side of the image?

This is an image from a product page. Notice that there’s a semi-transparent overlay at each side of the image, each containing the left and right arrows. The overlay should be eliminated, but the arrows maintained. Can that be done?

Please note: while the cursor is over the image is the time when the overlays appear. It’s on every product page with more than one image.

Link to the product page: https://www.perfectmakeupmirrors.com/serdaneli-hemisphere-limoges-porcelain-toothbrush-holder.html