Form creator can change page color schema

[growupanand]

Description

As a form creator, I want to match the form submit page colors with my company color theme.

Code of Conduct

• [X] I agree to be friendly and polite to people in this repository
• [X] I want to work on this issue and already read the Contributing Guidelines

[canny[bot]]

This issue has been linked to a Canny post: Form creator can change the form color schema :tada: