Dark Mode Pages
When editing a document, click on the upper right tab that says 'Document' next to 'Format'. Click the middle tab under the document tab titled 'Section'. Click on background and choose black. Then change the font color to white by clicking on 'Format' then 'Style' and choose white for the font dolor. Of course, if you don't want to submit your document as a black background, you'll have to reverse this before submitting. Hope this helps!
MacBook Air 13″, macOS 13.2