Css files generated, tecnical question

[TheElegantCoding]

I love CSS-IN-JSS, however, the bad thing is that it has made me not use it, I just found this library that seems to solve many problems, but I have some technical questions that I would like someone who has already used this package help me understand.

vanilla-extract continually compiles all the CSS into a?

If so, perfect, it is better to make a CSS request than several for each page, it is more efficient and faster

I would like to use svelte with vanilla-extract therefore.

Is it always necessary to create .css.ts files to define the styles?

With this question I mean, in all frameworks is this necessary? can styles not be used directly in the component file? do they have to be separate?

I wouldn't mind having the files apart, in fact, it may be a better structure when using sass normally you use a 7-1 architecture, BEM or SMACSS

My last question will be if it is possible to use those architectures that I mentioned before with vanilla-extract, since this library, being separate files, is a bit similar to the concept that sass has.

Thanks for everything, I would like to build a project with this library as an example and share it with the community.