function innerDivs(divClass, divNewClass, nbrDivs) {
  if (nbrDivs == 0) return;
  var divs = document.getElementsByTagName('div');
  var selected_divs = [];
  for (var i = 0; i < divs.length; i++) {
  	var reg = new RegExp("\\b"+divClass+"\\b")
    if (reg.exec(divs[i].className)) {
      selected_divs[selected_divs.length] = divs[i];
    }
  }
  for (var i = 0; i < selected_divs.length; i++) {
    var original = selected_divs[i];
    original.className = original.className.replace(divClass, '');
    var activDiv = document.createElement('div');
    activDiv.className = divNewClass;
    original.parentNode.replaceChild(activDiv, original);
	for (var j = 1; j < nbrDivs; j++) {
		var innerDiv = document.createElement('div');
		activDiv.appendChild(innerDiv);
		activDiv = innerDiv
	}
	activDiv.appendChild(original);
  }
}
function manageDivs(){
	innerDivs("title","title2",3)
	innerDivs("content","content2",2)
	innerDivs("footer","footer2",3)
}