[niralsoni]

Replace your current code (highlighted below) -

<script type="text/javascript">
$(document).ready(function() {
	$('.menu_items').mobilyblocks({duration:500, zIndex:10,	widthMultiplier:1.1});
    $('.switch').click(function(){
        if($('.switch').hasClass('menu_b'))
        {$('.switch').addClass('menu_s').removeClass('menu_b');}
        else
        {$('.switch').addClass('menu_b').removeClass('menu_s');}
     });
});	
</script>

with this one -

<script type="text/javascript">
$(document).ready(function() {
	$('.menu_items').mobilyblocks({duration:500, zIndex:10,	widthMultiplier:1.1});
    $('a.trigger').bind('click', function(){
        if($('.switch').hasClass('menu_b'))
        {$('.switch').addClass('menu_s').removeClass('menu_b');}
        else
        {$('.switch').addClass('menu_b').removeClass('menu_s');}
     });
});	
</script>

Hope it works for you...

Regards,
Niral Soni