Resizing main image on mobile - Hunter Template

Hi everyone, I'm having an issue with the main image displaying on the mobile side of our site. I want the mobile version to maintain the same (or similar) dimensions to the desktop version of its display. Other images on the site rescale to more horizontal dimensions, but this one doesn't - causing it to get cut off in a weird way.

I'm thinking it may have to do with my minimum height requirement for the main image (which I put in so that I got a larger main image). But am curious if there's a way to remove that height requirement in mobile.

I've included a couple of screen shots below. Website is unioncommon.com. If anyone has any code I could inject, or guidance, I would really appreciate it! Thanks so much!