How can I get rid of the gray/pinstripe background on this form?

I created this form last summer, obviously before some Jotform updates.  At the time, I wanted this gray background (it was actually called a "Theme") on my form.  But I'm updating the look of it now, and I can't find a way to delete it.  I want just a plain black color or maybe white.  Can you please help ASAP?

Thank you so much!

--Marcie.

I found it!  For others who may be having the same issue:

In form builder, go to "Preferences" tab, select "Form Styles," and change Themes to "Default."

It was SIMPLE.  I just didn't know where to do it!  ;)