Popup modal to unique CMS collection

Hi there, I’ve tried to make a unique grid for my CMS list. It worked fine with a code I got from a showcased website. But the only thing left is the popup modal… I added a high z-index to it, but when I try it out it seems like it gets behind the underlying CMS list. What can I do to make it popup in front of everything?

Here is my site Read-Only: Webflow - Copy of Vibrant