G'day jdlev,

Yes, there's a setting for that:

1. Go to your home node. You'll see Edit your: Profile, Settings. Follow the Settings link.
2. You'll now be at the User Settings page. You'll see See Also: Display Settings, .... Follow the Display Settings link.
3. You'll now be at the Display Settings page. In the fourth table (Code Listing Settings), you'll see Large Code Font with a checkbox. Select this checkbox.
4. At the bottom of the Display Settings page, hit Submit. Code should now be larger.

You'll also see on the Display Settings page: Stylesheet Settings. Here, you can link to an external CSS stylesheet or write your own custom CSS.