Ability to add another default color

[kbeck303]

Could there be an option to add a 3rd (and potentially a 4th and 5th) "static" color to test against?

right now there is a "light" and "dark" option, could there be a way to add another color to test against here? I know I could just run another report with the colors changed, but it would be nice to have it in a single report.

Use Case: If the is a dark and light background, but the sidebar background is a medium grey, and the footer is a 4th background color.