Aligning Thumbnails, Making Larger and Removing Scroll Bar I don't need

Site URL: https://www.suzykopf.com/shop/p/hawaiian-tropic-prints

Hi All, I know there are many posts about product thumbnails but I couldn't find any with ALL my woes. I am looking for code to help me center the images below the product, make them larger if possible AND remove the hideous scroll bar.

In order of priority to me: I want the scroll bar gone, I'd like them centered and it would be awesome to make the thumbnails larger but my reading here basically tells me that's not going to happen.

This page has all three issues but most of my products have this same problem because I've used variants to list multiples of the same items: https://www.suzykopf.com/shop/p/hawaiian-tropic-prints

Add to Design > Custom CSS

/* product page */
.ProductItem-gallery-thumbnails {
    overflow: hidden !important;
    margin: 0 auto;
    text-align: center;
}