You can use jQuery to access elements in another frame by accessing the jQuery object in that frame. You should always check if it exists (/ has been loaded yet) first.
if (parent.frames[1].$){ parent.frames[1].$(".suggestionsBoxBar").css('border','1px solid green'); }
That's helped me a lot !
http://www.kegles.com.br/arquivo/jquery-buscando-um-objeto-iframe-a-partir-de-seu-conteudo/