Change background color in Immersive Reader for OneNote

Sign into your account at Microsoft365.com, select Word or OneNote. Open your document, or a notebook page and select View > Immersive Reader 

• For Outlook online, log in at Office.com, select Mail, and open an email. Select More Options  , then Show in Immersive Reader.

Select the icon that looks like two As to open Text Options.

Under Themes, choose a color.

Open the OneNote app, then select View > Immersive Reader.

Select the icon that looks like two As to open Text Options.

Next to Themes, select the arrow to view color options and choose a color.