document.write("<style type=\"text/css\" media=\"all\">\n");
document.write(".hidenav { display: none; }\n");
document.write("</style>");
function showhide(elname) {
   var el = document.getElementById(elname);
   if(el != null) {
      if(el.className == 'hidenav') {
          el.className = '';
        } else {
          el.className = 'hidenav';
        }
     }
   }