Hello @matcha25, not necessarily. That depends on the structure of your document. Usually, you would have a main document with all your styling, and include other sub-files.
See Best practices for working with longer documents and its first link.
Yes, that’s the structure I’m using now. However, if I only have:
@show: thmrules
in the main document, I still see theorems center-aligned in the included sub-files. The only way to fix it seems to be to include @show: thmrules in all the sub-files.