Microsoft Office Ltsc For Mac 2021 V16.54.zip [repack] -

Full support for dark mode across all applications.

If you have acquired this .zip file, here is the standard procedure for handling this type of installer: Microsoft Office LTSC for Mac 2021 v16.54.zip

The latest version of Microsoft Office LTSC for Mac 2021, v16.54.zip, comes with a plethora of exciting features that enhance user productivity and experience. Some of the notable features include: Full support for dark mode across all applications

Pirated or unauthorized "repacks" of software often bundle hidden malware, trojans, or cryptominers. Microsoft Office LTSC for Mac 2021 v16.54.zip

To reiterate: You must be a Volume License customer.