Commerce Banner Changes Zoom When Resizing Window (Keep It The Same Size)

Site URL: https://www.khaircenter.org/build-the-mosque

For the commerce page of my site, I added an image banner/thumbnail to the top of the site. However, when I resize the window or move to mobile view, it either zooms into the image or doesn't show the whole image even at the biggest size. Is there a way to lock it so that the entire image shows?

Try adding to Design > Custom CSS

body#collection-614e3cb5038f8274a9a7430f .banner-thumbnail-wrapper img {
    width: 100% !important;
    height: auto !important;
    left: 0 !important;
}