Remove Whitespace between Gallery Images in Wells

Site URL: https://alnoormeralli.com/beauty

In the Wells template, the Gallery pages have a fixed-width whitespace separating the images / thumbnails.  Any way to remove the whitespace so the images appear "full-bleed"?

I want a look similar to Project 5 in Version 7.1, but want to continue using the Version 7.0 Wells template.

Add to Design > Custom CSS

@media screen and (min-width:641px) {
.collection-type-gallery.enable-gallery-thumbnails.thumbnail-view #thumbnails {
    display: grid !important;
    height: auto !important;
    grid-template-columns: repeat(3,1fr) !important;
    grid-gap: 0 0 !important;
}
div#thumbnails {
    height: auto !important;
}
.collection-type-gallery #thumbnails .thumb {
    position: static !important;
    padding: 0 !important;
    width: 100% !important;
    height: auto !important;
}}

That worked great!  But ran into an issue with some landscape images mixed in with the portrait images - they got squashed horizontally into portrait grid.  Is there a way of maintaining the image ratio for the landscape images (even if they go smaller to fit the vertical columns)?