WooCommerce product showcase size help!

Hello!

Im making a webshop via WooCommerce, and have a problem i hope someone can help me with, how do i get the picture to fit?? I figured out how to resize the pictures, so they look great when clicked a a single product, but in the showcase the picture is all wierd, how do i change this?

Here it is:

https://vapedinurt.dk/?post_type=product

Thanks in advance! ??