Changing font sizes in individual text containers

I added an additional "row" within a region that contains a new text element and the existing social media icons from the Scribe theme. I would like to make the text in that "row" smaller than the logo and menu "row". But I cannot for the life of me figure out how.

There is no font size option within the text element settings, every time I click on one of the social media icons it links me out to Twitter, etc, so I can't select them, I tried CSS for the text element but it is a default style and I only want to change that one. I went to the region settings and tried to do custom CSS there using the element classes provided, but nothing.

How am I supposed to do that??? Why isn't it a field or option somewhere?