jQuery's hide() and show() slow in Chrome

example.js

var $cssSelector = "display";
var $hideCSS = "none";
var $showCSS = "block";

if ($.browser.chrome) {
	$cssSelector = "margin-top";
	$showCSS = "0";
	$hideCSS = "-10000px";
}

$("#element").css($cssSelector, $showCSS); // For showing
$("#element").css($cssSelector, $hideCSS); // For hiding

useragent.js

(function($) {
    var userAgent = navigator.userAgent.toLowerCase();
    $.browser = {
        version: (userAgent.match( /.+(?:rv|it|ra|ie)[\/: ]([\d.]+)/ ) || [0,'0'])[1],
        chrome: /chrome/.test( userAgent ),
        safari: /webkit/.test( userAgent ),
        opera: /opera/.test( userAgent ),
        msie: /msie/.test( userAgent ) && !/opera/.test( userAgent ),
        mozilla: /mozilla/.test( userAgent ) && !/(compatible|webkit)/.test( userAgent )
    };
})(jQuery);

workaround.js

$element.css('margin-top', '0'); // For showing
$element.css('margin-top', '-1000000px'); // For hiding