FILE CSS
.megamenu{
position: absolute;
display: none;
left: 0;
top: 0;
background: white;
border: 1px solid #008000;
border-width: 5px 1px;
padding: 10px;
font: normal 12px Verdana;
z-index: 100;

}

.megamenu .column{
float: left;
width: 180px; /*width of each menu column*/
margin-right: 5px;
}

.megamenu .column ul{
margin: 0;
padding: 0;
list-style-type: none;
}

.megamenu .column ul li{
padding-bottom: 5px;
}

.megamenu .column h3{
background: #e0e0e0;
font: bold 13px Arial;
margin: 0 0 5px 0;
}

.megamenu .column ul li a{
text-decoration: none;
}

.megamenu .column ul li a:hover{
color: red;
}
FILE .JS
/* jQuery Mega Menu v1.02
* Last updated: June 29th, 2009. This notice must stay intact for usage
* Author: JavaScript Kit at http://www.javascriptkit.com/
* Visit http://www.javascriptkit.com/script/script2/jScale/ for full source code
*/

jQuery.noConflict();

var jkmegamenu={

effectduration: 300, //duration of animation, in milliseconds
delaytimer: 200, //delay after mouseout before menu should be hidden, in milliseconds

//No need to edit beyond here
megamenulabels: [],
megamenus: [], //array to contain each block menu instances
zIndexVal: 1000, //starting z-index value for drop down menu
$shimobj: null,

addshim:function($){
$(document.body).append(``)
this.$shimobj=$("#outlineiframeshim")
},

alignmenu:function($, e, megamenu_pos){
var megamenu=this.megamenus[megamenu_pos]
var $anchor=megamenu.$anchorobj
var $menu=megamenu.$menuobj
var menuleft=($(window).width()-(megamenu.offsetx-$(document).scrollLeft())>megamenu.actualwidth)? megamenu.offsetx : megamenu.offsetx-megamenu.actualwidth+megamenu.anchorwidth //get x coord of menu
//var menutop=($(window).height()-(megamenu.offsety-$(document).scrollTop()+megamenu.anchorheight)>megamenu.actualheight)? megamenu.offsety+megamenu.anchorheight : megamenu.offsety-megamenu.actualheight
var menutop=megamenu.offsety+megamenu.anchorheight //get y coord of menu
$menu.css({left:menuleft+"px", top:menutop+"px"})
this.$shimobj.css({width:megamenu.actualwidth+"px", height:megamenu.actualheight+"px", left:menuleft+"px", top:menutop+"px", display:"block"})
},

showmenu:function(e, megamenu_pos){
var megamenu=this.megamenus[megamenu_pos]
var $menu=megamenu.$menuobj
var $menuinner=megamenu.$menuinner
if ($menu.css("display")=="none"){
this.alignmenu(jQuery, e, megamenu_pos)
$menu.css("z-index", ++this.zIndexVal)
$menu.show(this.effectduration, function(){
$menuinner.css(`visibility`, `visible`)
})
}
else if ($menu.css("display")=="block" && e.type=="click"){ //if menu is hidden and this is a "click" event (versus "mouseout")
this.hidemenu(e, megamenu_pos)
}
return false
},

hidemenu:function(e, megamenu_pos){
var megamenu=this.megamenus[megamenu_pos]
var $menu=megamenu.$menuobj
var $menuinner=megamenu.$menuinner
$menuinner.css(`visibility`, `hidden`)
this.$shimobj.css({display:"none", left:0, top:0})
$menu.hide(this.effectduration)
},

definemenu:function(anchorid, menuid, revealtype){
this.megamenulabels.push([anchorid, menuid, revealtype])
},

render:function($){
for (var i=0, labels=this.megamenulabels[