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 https://vaadin.com/docs/latest/components/side-nav/styling

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