Styling Parent Categories

Apologies if it has been covered but does anyone know if it is possible to style a Parent category link in the sidebar differently to it’s Children categories?` Even if only a different colour.

It would be nice also not to show the post count on Parents if they are zero whilst retaining posts on Children but I fear that is going to be in the list_cats and wp_list_cats code but if you know a way I’d love to hear of it.

Thanks