Do you use Sass with CSS Modules? I've found it to be an excellent pairing. I put shared styles/variables (like colours) in top-level Sass partials that individual component styles can import if they need them.

The only part I dislike about CSS Modules is having to use camelCased class names, or string references (styles['class-name']), which always feel awkward. I prefer kebab-case for CSS because it's a lot more flexible (more word separators: "-", "--", "_", "__", etc.), but I'm sure I'll adapt.