/***********************************************
* Drop Down/ Overlapping Content- © Dynamic Drive (www.dynamicdrive.com)
* This notice must stay intact for legal use.
* Visit http://www.dynamicdrive.com/ for full source code
***********************************************/

function getposOffset(overlay, offsettype){
var totaloffset=(offsettype=="left")? overlay.offsetLeft : overlay.offsetTop;
var parentEl=overlay.offsetParent;
while (parentEl!=null){
totaloffset=(offsettype=="left")? totaloffset+parentEl.offsetLeft : totaloffset+parentEl.offsetTop;
parentEl=parentEl.offsetParent;
}
return totaloffset;
}

function overlay(curobj, subobjstr, opt_position){
if (document.getElementById){
var subobj=document.getElementById(subobjstr)
subobj.style.display=(subobj.style.display!="block")? "block" : "none"
if (opt_position=="center") {
  var xpos = (window.innerWidth / 2) - (subobj.offsetWidth / 2);
  var ypos = (window.offsetHeight / 2) - (subobj.offsetHeight / 2);              
} else {
	var xpos=getposOffset(curobj, "left")+((typeof opt_position!="undefined" && opt_position.indexOf("right")!=-1)? -(subobj.offsetWidth-curobj.offsetWidth) : 0) 
	var ypos=getposOffset(curobj, "top")+((typeof opt_position!="undefined" && opt_position.indexOf("bottom")!=-1)? curobj.offsetHeight : 0)
}
subobj.style.left=xpos+"px"
subobj.style.top=ypos+"px"
return false
}
else
return true
}

function overlayclose(subobj){
document.getElementById(subobj).style.display="none"
}