Add a Horizontal Rule after buttons

Hello,

I’d like to add a Horizontal Rule (or any sort of line) underneath the simple share buttons. I have the buttons at the top of my page and I’d like to space them a little from the main page below using a line.

I’ve gone to the “Additional CSS” area of SSBA settings and have been tinkering with “after:” and “content” but can’t get an <hr> or line to appear.

I’m very new to all of this so any simple way to do this would be much appreciated. It’a an internal website so can’t post a link I’m afraid.

Thanks,

Rob

https://wordpress.org/plugins/simple-share-buttons-adder/