Creating 2×2 Table of Images > Mobile Spacing Issue

I am trying to create a 2 x 2 table, where each quadrant has an image (with link).

I have added a row and configured it to be 2 columns.

I then added a “Single Image” content block in each one.

On desktop this is achieving the desired effect, which is perfect.

However, on mobile, it is creating a TON of spacing between each image (both above and below it).

I’ve been trying to edit the CSS, but I can’t seem to get it to work at all.

Can someone please help?

URL: https://ponypulse.com/
Password: winning

Thanks in advance!