"Your latest posts" posts get highlighted in blue

Dear All,

I’m using this theme for an internal knowledge base. When someone writes an article and it shows up on the latest posts front page (static front page -> front page displays your latest posts setting) the post is highlighted in a bluish colour which is very jarring compared to the colour scheme of the site itself.

How can I turn this off? I’ve disabled all addons to check if something else caused this, but no luck. It seems to be linked to the theme somehow.

As the site is internal I cannot link it, however, I have some screencaps. I’ve cut these from the front page.

Highlighted post:

This is the blue highlight, on the right you can see the white content background.

Normal post blending into background:

This is an older post with no highlight, blending into the content background.

Thanks.