With almost every application offering a dark mode option, Microsoft was not left out, this is not a new feature though. Microsoft first released its black and dark gray mode theme on its suite in December.
The dark mode is considered safer especially if working in conditions were light can easily reflect, according to Microsoft, you can only access these feature if you are using Microsoft 365 (previously known as Office 365). Office 2016 and office 2013 can let you change to “dark grey” theme only without the “dark mode”
To change your theme, click the “File” menu at the top left corner of an Office application like Word, Excel, Outlook, or PowerPoint.
To enable dark mode, select “Black” for the darkest possible Office style.
“Office Backgrounds” can also help you design behind Office’s ribbon bar which appears on the top right corner.
Note, these themes affect all Microsoft Office applications on your system so there is no need to go change them one by one.