I made this little jQuery function to make my navigation slide out on mobile devices. My only problem though... I can only show and hide it once... Can anyone help me out with this? Thanks in advance!

```
$('#menu-btn').click(function(){

  if ($('nav ul').css('margin') == '83px 0px 0px -225px') {

    $('nav ul').animate({
      margin:'83px 0px 0px 0px'
    }, 200);

  }
  else {

    $('nav ul').animate({
      margin:'83px 0px 0px -255px'
    }, 200);

  }

});

```