Thin White Line Below Images

Hello,

I suddenly have a problem on my business site that hadn't been there previously: Thin white lines appear just below the images on the homepage but disappear on hover. They also don't appear in the dashboard. I can't figure out how to fix this. 

https://www.causeandmatter.com/

Thanks for any advice.

It looks fine on my Windows/Chrome

You try checking it again on some browsers/devices

Yes, I figured it out. Thank you, though! It was a hangover style in CSS.