[Plugin: Just the Page] Only plain text is shown – all theme css styles gone

Hi,
Thanks for the plugin – just what I needed.
But I have a problem. When checking the box to get rid of the header and footer all my theme css styles are gone as well.
No formatting left – just plain text.
Please let me know if you can fix it.
I use a child-theme in this case.

Thanks
Robert

http://wordpress.org/extend/plugins/just-the-page/