I'm trying to develop a FSE theme from scratch for a multisite network using Create Block Theme plugin , and because of built in responsive functionality I've decided to use Spectra plugin.

The problem is that even if I can see and use Spectra's editor functionalities and I can see them working on Site Editor page, when I visit the site nothing works as supposed to. After some page inspection I've seen that no styles where applied for Container and other Spectra's blocks. If I use Spectra One theme all working fine and functionality is doing what supposed to do.

My question is: considering I created a them from scratch, do I need to include .cssand .js files manually? Ain't them supposed to be included with plugin activation? What is the right way to do it?

WordPress 6.7.1
Spectra 2.18.3