Button on mobile overlay navigation can't be seen

This is what is showing up on our mobile overlay navigation. The footer bar at the bottom is covering up the green button.  All of the links (including the button sliver and the footer bar links) work, you just can't read what the green button is supposed to take you to.

You can't scroll the overlay nav menu, and I don't want to get rid of that footer bar, so how can I fix the spacing so that the button text can be seen? 

I know you can change the font size with custom CSS so this seemed like the best forum to ask if there was a custom CSS solution to solve this problem since this is not handled at all by the standard settings.

Thanks in advance for your help.

Can you share your website URL?

clarksburgchurch.com

Once I found the custom CSS area, it worked! Thanks!!