Polymer "skinning" question

[Mike Fielden Jr.]

Hello guys hopefully this community can help me out. 

I posted a semi-related question about this on StackOverflow 

However, I have a slightly more general question. Lets say I want to skin a core-toolbar. Add no functionality to it just simply change the color, bg-color, and some other general things for a project I'm working on to use their branding colors, fonts etc. 

Should I create a component called "companyA-toolbar" (which is what the StackOverflow question is about) OR should I just have some classes I can apply to the core-toolbar to make it look the way I want?

core-toolbar.companyA {
  color: purple;
  background: gold;
  ......
}