CSS Selector “(A or B) and C”?

Question

This should be simple, but I\'m having trouble finding the search terms for it.
Let\'s say I have this:

Foo


        
      

Answer 1

is there a better syntax?

No. CSS' or operator (,) does not permit groupings. It's essentially the lowest-precedence logical operator in selectors, so you must use .a.c,.b.c.