Correct CSS reference to remove the header and menu?

Hi there,

I would like to know how to remove the header + menu + breadcrumb trail from single posts when opened from a specific page. The page id is page-id-2526. In previous conversations with support, the following code was suggested. However if doesn’t remove the header. can you tell me what is wrong with the following syntax or what I need to add to remove all three of those sections?

I tried:
.page-id-2526 .single-post #header, .single-post #main-navigation-wrapper, .single-post .breadcrumb-wrapper { display:none !important; }
.page-id-2526 .single-post #content-inner { padding-top: 0px !important; }

I am trying to get this working on a page at:
http://r3demo.com/green-room/

Thank you for any suggestions.