Seeking Guidance: Creating a Custom Theme for Hilla Components in My Non Hilla React project

I am using hilla components in my pure react project where i am not using hilla platform. I researched lot of component library but they required lot of code. Hilla components are very easy to use but now i want to customize theme. Any one suggest me how i can do in non hilla platform ?

If you go to the docs of the components and select the styling tab you can see possible public available css selector e.g. here

The usage of Lumo CSS custom properties and part selectors as described in the documentation should work universally.