My menu works fine in chrome but not in IE!!!

I saw that.
you know I write Jquery code for my menu but that jquery does not work in IE
here is my jquery:
/*Desinged By "B@h@reh.$h@r!f!@n" 22-01-2014*/
$(document).ready(function () {
$("#mainMenu ul").css({
"position": "absolute",
"margin": "0",
"padding": "0"
});
$("#mainMenu").css({
"position": "relative"
});
$("#mainMenu > li").css({
"display": "inline-block"
});

$("#mainMenu > li > ul").css({
"display": "none"
});
$("#mainMenu > li > ul ul").css({
"top": "0px",
});

$("#mainMenu li").css({
"list-style": "none",
"position": "relative",
"margin": "0",
"padding": "0"
});


var param = $('#mainMenu').attr("dir");
if (param == "ltr") {
$("#mainMenu > li > ul").css("left", "0");
}
$("#mainMenu li").mouseenter(function () {
$(this).parent().find("ul").css("display", "none");
if ($(this).find(">ul") != undefined) {
$(this).find(">ul").css("display", "block");
if ($(this).parent().attr('id') != "mainMenu") {
if (param == "ltr")
$(this).find(">ul").css("left", $(this).width());
else {
$(this).find(">ul").css("right", $(this).width());
}
}
}
});
$("#mainMenu").mouseleave(function () {
$("#mainMenu").find("ul").css("display", "none");
});


})

would you please tell me what to do?

Thanks a lot,It just work