Give the letters another color??

Dear support,

I use your Contact Form 7. It’s a great Plugin. Many thanks for that.
However I have a (little) problem: My website is black. Therefore visitors and me cannot see the information for each field. To make them vissible the letters should have another color. Is it possible to change the black color to another color?

I wanted to send also a screenshot, but I don’t see how I can do this here :-((

Regards,

Joyce