Overengineered Rating Component with React Routes and Redux

I'm very new to the front-end side of development. I just finished a course on Scrimba and now I'm starting to create some front-end muscle on the FrontEndMentor.

I'm not really secure about my CSS and would like some feedback if possible.

Also I used Redux, not because it's needed, I could do a little of prop drilling, but because I want to learn about it because it's a important library. Did I used it right?

Also some questions about best practices on React. I tried to make different components. The way I made it is correct?

Thanks for any feedback!