Did your counselor mention this in their LoR? They should, although at many schools it won’t lessen the impact of the B’s and C’s (assuming some of those happened junior year.) You can mention it in C&C or addt’l info common app sections, but just keep it short and fact based.
I get it. Colleges that recalculate are going to do what they are going to do. I know you said your school doesn’t rank, but where do you think you fall? Top 10%? Top 25%? etc. If you don’t know ask your counselor. And use naviance/scoir if you have one of those/ something like those. I will say the vast majority of Villanova unhooked admits will have all A’s. Some will have a couple of B’s. I doubt many have C’s.