Pin Button to page and keep interactive while placed at header

@toniabkscorsese
When working with HEADER and BODY, or FOOTER you should always pay attention on following things…

  1. blue-body-area should not cross the orange-header-area.
  2. using strips may solve some responsivibility-problems.
  3. menus can be created by using multistate-boxes inside header and footer (for example)
  4. also the usage of expanding and collapsing the header and footer elements can help.