MyBB Community Forums

I was copying some text by typing control C, and I must have hit another key too, and suddenly the font on the entire forum decreased in size. I want to restore my forum to the size that it was. How do I do that, in a simple way? I am not knowledgeable about css. If I could hit a key and make the font smaller for the entire forum, there must be a way to put it back the way it was.

The MyBB forum I am using is http://generational-theory.com/forum

You've probably just zoomed out on your browser, it's only changed for you and not for everyone. Press Ctrl and + if you're on Windows or Cmd and + if you're on a Mac and it should zoom back in.