$(document).ready(
     function () {
          //On Hover Over
          function hoverOver() {
               $(this).find(".sub").fadeIn('fast'); //Find sub and fade it in
               $(this).css({ "z-index": "1000" });
               (function ($) {
                    //Function to calculate total width of all ul's
                    jQuery.fn.calcSubWidth = function () {
                         rowWidth = 0;
                         //Calculate row
                         $(this).find("ul").each(function () { //for each ul...
                              rowWidth = $(this).width(); //Add each ul's width together
                         });
                    };
               })(jQuery);

               if ($(this).find(".row").length > 0) { //If row exists...
                    var biggestRow = 0;
                    $(this).find(".row").each(function () {	//for each row...
                         $(this).calcSubWidth(); //Call function to calculate width of all ul's
                         //Find biggest row
                         if (rowWidth > biggestRow) {
                              biggestRow = rowWidth;
                         }
                    });
                    $(this).find(".sub").css({ 'width': biggestRow }); //Set width
                    $(this).find(".row:last").css({ 'margin': '0' });  //Kill last row's margin
               } else { //If row does not exist...
                    $(this).calcSubWidth();  //Call function to calculate width of all ul's
                    $(this).find(".sub").css({ 'width': rowWidth }); //Set Width
               }
          }

          //On Hover Out
          function hoverOut() {
               $(this).find(".sub").fadeOut('fast', 0, function () { //Fade to 0 opactiy
                    $(this).hide();  //after fading, hide it
               });
               $(this).css({ "z-index": "1" });
          }

          //Set custom configurations
          var config = {
               sensitivity: 1, // number = sensitivity threshold (must be 1 or higher)
               interval: 1, // number = milliseconds for onMouseOver polling interval
               over: hoverOver, // function = onMouseOver callback (REQUIRED)
               timeout: 250, // number = milliseconds delay before onMouseOut
               out: hoverOut // function = onMouseOut callback (REQUIRED)
          };

          $("ul#topnav li .sub").css({ 'display': 'none' }); //Fade sub nav to 0 opacity on default
          $("ul#topnav li").hoverIntent(config); //Trigger Hover intent with custom configurations
     }
);