Fix card sizes on Academic

Dear users,
I am building a basic site using Hugo Academic:

As suggested in the github page of the theme, I have reused the ‘Project’ widget to create the team’s one.
I cannot, however, fix the size of each card so that they look nice. I have looked through the CSS hierarchy, but was unable to find where the sizes are set. They seem to react to image size.
Any thoughts on how I can set the sizes to a fixed value?
Thank you very much