use more than one theme

Hi;

use more than one theme with one db ist?yorum logic alone will soyle;

A main theme https://www.AAA.com site
111.aaa.com subdomain with a different theme
222.aaa.com a different theme

only difference I Do as follows to create, and it’s a category of each subdomain will be composed of sub-categories. In fact I would like to establish a theme for each category separately.

How do I perform it without installing more than one db.

Thanks