How to edit background color in CKForm?

[Peter2009]

Hi there,
my template has a black background and the font in my 'textarea' field is also black... how can I change the font color... or the background color?
I know, I can edit CSS... but where exactly do I find it and where to change?
Thanks Peter

[Peter2009]

I would need the same css style (white font on gray background) from the 'text' field for the 'textarea' field.

Thanks