function change(html){
  descripcionopciones.innerHTML=html
}

var tags = new Array( 'div');
var pixelArray =  new Array('10','12','16','20','24','30','40');
var emArray =  new Array('0.7','0.9','1.0','1.5','2.0','2.5','3');
var initSize = 1;

function fontSizer(inc,unit) {
	if (!document.getElementById) 
		return;
	var size = initSize;
		size += inc;
	if (size < 0 ) {
		size = 0;
}
	if (size > 3 ) {
		size = 3;
}
		initSize = size;
		getBody = document.getElementsByTagName('body')[0];
	for (i = 0 ; i < tags.length ; i++ ) {
		getallTags = getBody.getElementsByTagName(tags[i]);
	for (k = 0 ; k < getallTags.length ; k++) 
	
	if (getallTags[k].className == "cuerpo"){
		getallTags[k].style.fontSize = (unit=='px') ? pixelArray[size]+unit: emArray[size]+unit;
		}
	}
}

var req = false;
function loadXMLDoc(url, funcProcess) {
   req = false;
   if(window.XMLHttpRequest) {
      try {
         req = new XMLHttpRequest();
      } catch(e) {
         req = false;
      }
   } else if(window.ActiveXObject) {
      try {
         req = new ActiveXObject("Msxml2.XMLHTTP");
      } catch(e) {
         try {
            req = new ActiveXObject("Microsoft.XMLHTTP");
         } catch(e) {
            req = false;
         }
      }
   }
   if(req) {
      req.onreadystatechange = funcProcess;
      req.open("GET", url, true);
      req.send(null);
   }
}