You can namespace all CSS rules. It's annoying in CSS, but really easy in LESS and SASS.
e.g.
my-namespace {
.button {
color: red;
}
.another-button {
color: blue;
}
}
The namespace can be a custom element name, a class or an ID.
The problem with this approach is that you need to declare the namespace in DOM somehow, and depending on the project that can either be easy or rather difficult. I used this technique when I ported a stand-alone application with classes just like ".button" to be a single page in a larger application, and it worked fine.
Anyway, I do think that CSS should have a proper solution to modularization.
EDIT: Now that I could open the link (it didn't open for me previously), I now see that this approach doesn't solve the problem with the article, since it doesn't support nested namespaces. (Although a hacky solution would be a 'reset all rules' helper in the inner namespace).
