iTunes synced over multiple PC's using Dropbox flawlessly BUT what if I add a Mac?

My entire iTunes library is in Dropbox and synced (and backed up - that music is precious!) across multiple PC's. Obviously only 1 PC at a time can use the library, but the concept is absolutely flawless for adding music, updating metadata and so on. The way Dropbox syncs is extremely efficient, plus re-assuring knowing my music is not only backed up in the cloud but also sitting on 3 other hard drives.

I want to add a Mac now and wondered if any of you know how that would work? Does Apple Music use the same library? I'd have thought the file structure would be different? I literally can't find an answer online and I'm sure I can't be the first person in the world to want to do this and would really appreciate the help and knowledge of you experts on this.