I have a website with menu items assigned by default to the Cassiopeia template because, since it's a management software, I thought it was the most suitable. However, I'd like to change the menus using a template based on the Helix Ultimate Framework, such as Optimax (already installed). Isn't there a way to use the Optimax template (and Mega Menu) just for the menus and open all the pages (lists and Fabrik forms) in Cassiopeia?