Project section icons are no longer squares in desktop display

I just updated my wordpress to the version 5.5.1 and then I updated my illdy theme to the version 2.1.7.
My issue is that before the wordpress update in the “projects section” of the home page, each project was represented by a square image (and it was nice to me) and now the square are rectangles. I notice that the wider is my screen, the smaller is the height of the image (so when I’m on my phor the images of the project are almost square)
How can I fix that, I need to get back to the square images (the problem is that when the images are rectangles, the image are very croped and it’s not very nice, we can’t see half of the image…)

Thank you

hey there

Please provide a link to the page and screenshot of the problem