Hi Joe,
One way is to use Tom’s fantastic plugin Simple CSS:
https://wordpress.org/plugins/simple-css/
In addition to adding a CSS area in the Customizer as well as a standalone CSS editor area (Appearance > Simple CSS) it also adds a CSS meta box for each page/post where you could add the following to provide a background image for the content area for just that page:
.entry-content {
background: #ff3300 url("URL_TO_THE IMAGE");
}
Note that the color is the fallback color should the image become unavailable; set to whatever you want/need 🙂
Cheers!
Lyle
http://snifflevalve.com
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