Foundation Site Styles and Custom Fonts

So I’ve been able to use Google Fonts with Foundation Headers but I’m curious about something. The Custom Definition option within Site Styles has a selector field which defaults to h2,h3,h4,h5,h6 (see attached). But if I change that field to just h2 for example it still seems as if the custom font is applied to all headers. I guess I was hoping I could assign a different custom font to each of the header types (not really sure I’d actually want to do this from a design point of view - mostly just trying to wrap my head around options as I learn RW + Foundation). I guess I don’t understand the point of the selector option if it just applies to all the headers (at least h2-h6) anyway. It would seem to me that changing that selector option to h2 for example would pop up another field which would allow for the h3-h6 option - and this new field option would continue to pop up as I customize each header type individually. Thanks for any thoughts. Again I’m not sure this is something I actually need to do - just curious.