The following three choices are available in the Customize Your Copy of Microsoft Office segment:
User Name: In this text box, you may alter the preferred writer for new workbooks produced with Excel 2021.
Background in the Office: This drop-down box lets you choose a faint background style for the right-hand side of the Excel program window, which includes your title, the Ribbon Display choices, and the Restore, Minimize, and Close buttons. After picking one of the available backdrop designs, select the No Backdrop choice at the top of this drop-down option to return to the standard of no pattern in this part of the screen.
The theme for the Office: The Multicolor, Light Gray, and White tint choices are applied to the edges of the Excel screen, generating a form of backdrop color for the Ribbon tabs, column alphabet and row numbering markers on the worksheet border, and the Status bar, respectively.