Easy Blogging - how to add custom css?

I use Easy Blogging for a customer's admin area, but have added a new metabox/dashboard widget (GREAT new feature, by the way) that needs to have additional css, a list of member's own custom posts with thumbnails.

Tried adding css to admin header, which works when in standard more, but the Easy Blogger seems to overwrite or remove the styles when in Easy mode.

Is there a way to add custom styles directly to an Easy Blogger theme in a way that won't get overwritten with the plugin update?