How do you style react components?

Question

React

Good afternoon, we use React and Material-ui in our project on the client side. In principle, we somehow lived using withStyles and className, styling each component separately, but now we are faced with the fact that the component, consisting of other small components written by us and material ui components, is drawn on the layout differently on the page and in the modal window, in this regard, we finally asked ourselves what to do in such a situation, if we need all its functionality, but in a different shell? What's the best way to style in React apps? What practices are now considered best for such cases?