Set subpage menubar same as parent menubar

Hello peoples! I'm having a sort of a problem here... I have a menubar with 8 main pages. Three of those pages show a different colored menubar if the visitor clicks on it. If I add submenu's to any of the colored parent pages. The submenu shows up in the default color green. It does not show up in the color of the parent page. I would like to know how it would be possible to add a subpage in the admin panel (because it is for a cliënt) showing up with the same menubar color as the parent page.

I set the color of the parent page menubar in style.css with .page-id-23 #access {blabala}.
I can also do this with the subpages, but then I have to create them first. I do not want that ofcourse. Can anyone help me out.....?