How do I create a fixed solid color background, with scrolling white blog posts?

[sachnique]

I just want my background to be something other than white, but not change the blog post. Kind of like this page, the background is a bluish/gray, but the text box I am writing in, is white. I believe I have haberdasher theme.

My site is roseandholland.com

[Adam7]

One thing you could do is use a single section element on each page of your site to contain all your content.  Sections can have solid color backgrounds, so they'd be an easy way to achieve what you want:

https://hc.weebly.com/hc/en-us/articles/227027928-Adding-Sections-to-Your-Pages

Another thing you could do is use a theme that has a background color you like, then use sections to have white areas on top of the background.