Unable to change site background in Styles

I've updated the nav, footer, and section backgrounds in the styles to be the same style with dark background but when in desktop version if you minimize the size of the window a white bar appears. I am trying to make the whole website background black.

Any ideas on how to change that default so it's not just section backgrounds.

Thanks for your help

That worked, thank you!

Curious that code would likely apply to all pages - how would you have it be for a specific page and not the whole website.

5 hours ago, Claibuco said:

That worked, thank you!

Curious that code would likely apply to all pages - how would you have it be for a specific page and not the whole website.

You can add code to Page Header Code Injection