[Plugin: Register Plus] Custom CSS for Register & Login Pages

I just modified the “User message” in the “Customize User Notification Email” section to remind people registering to look for the second email and to confirm their email address. That was easy for me because the base info was there.

Now I would like to know how to use the “Custom CSS for Register & Login Pages” fields to beef-up and personalize my blog.

Could someone please show me an example or two of how they used these two fields?

Thanks,
Mike