function flexMenu(id)
{
 var $id = document.getElementById(id);
 var titleList = $id.getElementsByTagName('h2');
 var contentList = $id.getElementsByTagName('div');
 titleList[titleList.length-1].style.border = 'none';
 for(var i=0;i<titleList.length;i++)
 {   
  titleList[i].onclick = function()
  {
   for(var a=0;a<contentList.length;a++)
   {
    contentList[a].style.display = 'none';
   }
   if(this.nextSibling.nodeType=='3')
   {
    this.nextSibling.nextSibling.style.display = '';
   }else
   {
    this.nextSibling.style.display = '';
   }
   
  }
 }
}
window.onload = function(){ flexMenu('boxx')}