media query change image ratio

Hi,

I have been trying to implement posts in the bottom of the blog post with a 1:1 featured image; however, on mobile, the following media query changes the images to 16:9 and leaves empty space under the image when it stacks. I have previously patched these by editing theme files, but newer updates overwrite that. Is there a solution for that as well, like a child theme?

@media only screen and (max-width: 599px) {
  .single .wp-block-query .wp-block-post-featured-image, .single .wp-block-query .wp-block-post-featured-image a, .single .wp-block-query .wp-block-post-featured-image img {
    height: auto !important;
  }

this also happens when not stacked btw

The page I need help with: [log in to see the link]