Changing the title fonts of widget sidebar

Dear HB themes. I would like to be able to change the title font of the widgets in the sidebar. I like the font shown in my navigation menu but it is too hard to read in the black semi-transparent sidebar. I would like to have my Headings 2 Font which is Open Sans.

I have attached a word document with a print screen that shows the problem font in the sidebar.

Thank you for your assistance.

Lisa Colburn