!!!
%html{:lang => "en", "xml:lang" => "en", :xmlns => "http://www.w3.org/1999/xhtml"}
  %head
    %meta{:content => "text/html; charset=UTF-8", "http-equiv" => "Content-Type"}
  %body{:onload => "number_pages"}
    #header
    #content
      = yield