Changing the Font Size of CM6

There is a similar thread to this, however it doesn’t solve my problem. I would like to change the font size and font family of the editor text using CM6. The solutions I can find online only apply to CM5 and below. Since I can’t hack the CSS manually, are there any editor methods for setting the styles I need?
Thanks.

Create a small theme that sets a font size on the wrapper or the content element, and add it to your configuration.