Create examle PR using CSS modules.

The vanilla CSS solution we currently have is messy, leads to potential CSS clashes.

I don't want to use a CSS-in-JS solution, because that unnecessarily inflates the bundle size.

I want to know if CSS modules will solve the problem of:

1. Allowing a package to by default have its own opinionated styling
2. Not inflate the JS bundle with CSS.
3. Allow the default styling to be overridden
4. Have the CSS be cachable by the ultimate consuming code.

Instructions:

Create a comment outlining the problem space and approaches forward.
Create a demonstration PR that achieves these goals, or demonstrates why it's not possible.