Hiding Masthead to Breadcrumb per page

I was previously able to do this using this code: .page-id-51 #masthead, .page-id-51 #menu-main-menu, .page-id-51 #breadcrumb-list { display: none; } Now that I have the search embedded in the Nav, I've tried several variants of: .page-id-51 #masthead, .page-id-51 #nav-primary, .page-id-51 #breadcrumb-list { display: none; } but the nav still shows... please help