How can I fix this encoding issue?

Hey so I'm creating a forge mod and I'm trying to use the "§" character but I'm getting an illegal character error in the compiler. I've tried using the -encoding option in the compiler, I've also tried converting the file to UTF-8 without BOM, but it wasn't UTF-8 BOM in the first place. I was making a jar mod with mcp in eclipse and everything was working just fine with these characters, which I'm now moving to a forge mod. I'm using IntelliJ Community IDEA currently.

Here's a link to part of the error list: https://jay-hosts-a.dark-web.store/6AXsbJqG. Obviously the other errors were due to the illegal character error but I thought I might as well show it.

I'm making a forge mod for 1.12.2, forgegradle is version 2.3-SNAPSHOT and I'm using mixingradle-0.6-SNAPSHOT.

I'm not sure how to fix this and any help would be greatly appreciated.