fade and slide menu very 'sluggish'

fade and slide menu very 'sluggish'

Hi guys,

Im having a really hard time with this any help would be really really appreciated.

I am using jquery to have a sort of 'fade and slide' menu system. The code im using is:

<script type='text/javascript'>
$(function(){
     $('.show_content').each(function(){
          var $item = $(this);
          $item.bind('click', function(event){
               event.preventDefault();
               $('.xx').animate({
                    marginLeft : '-240px',
                    opacity : '0'
                    }, 500, function(){
                         $('#' + $item.attr('alt')).animate({
                              marginLeft : '0px',
                              opacity : '100'
                              }, 500
                         );
                    }
               );
          });
     });
});
</script>


I finally have it working like i want it to but the whole thing is soooo sluggish. I have put a sample page here: http://cart3.jaspers-sensations.com/tester.html

Its fairly self explanitory, depending on the menu item you click (eg menu a_a) a sub-menu slides in on the right. If you click on a different item (eg a_b) that sub-menu slides out and a different menu slides in. However, it seems to run v. slowly with a huge lag between the new menu sliding in (happens first) and the old menu sliding out (transparancy means you can still see the old menu under it)

Any ideas about how i can speed things up and make it a bit more slick?

thanks very much in advance for any help.

Matt