wp-post-image Circles invisible in Child Theme/Google Translate

Hi, thanks for your beautiful theme,
I’m brand new to .css editing, but found your code nicely laid out and labelled to be understood.

I’m building this site whatsbehindjnf.org (still under construction)
Mostly its working well (sorry if i’ve destroyed your beautiful design)

However the gallery of posts on the front page is invisible unless hovered when the site is run through google translate, (using links in footer widget)

The same is also true when I created a child theme (only style.css changed) – i know i should have created a child theme from the start but just now learnt that i needed to do that.

Any clues as to what might be going wrong?