I was given an InDesign document that somehow managed to have the background color of the page be turned black (as shown in the image below) and I am trying to change it back to the default white. In trying to figure this out, I am using the latest version of Adobe InDesign (v16.1) on macOS.
I have seen some references online to setting the page background color by drawing a box. So, the spread above that has this issue inherits from the A-Master, which also has the black background. As shown in this image under layers, there are no rectangles, boxes, etc. on the master spread which could be causing the black background.
The last piece of data that I have is when exporting the book, the black background does not show up.
So, my question is what could be causing the black background and what could be done fix this issue?