Removing Out of Stock badge

Hi, I have an art page and installed the Sold Out Badge for WooCommerce. I am trying to replace the Out of Stock banner with a red dot for products that are sold. I was able to add a red dot successfully whenever a product is out of stock (as set in the Product Inventory setting). However I am unable to get rid of the Out of Stock banner. I tried adding Additional CSS:
.out-of-stock-badge {
display: none !important;
}
as you’d suggested in one of the posts but that didn’t make any difference. Do you have any suggestions on what else I can try?
Thanks in advance!

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