$(function(){

	$('ul.nav li')
		.css( {backgroundPosition: "-20 -5"} )
		.mouseover(function(e){
			
				$(this).css("cursor","pointer");
				$(this).stop().animate({backgroundPosition:"(10 -1)"}, {duration:200})
				

           
		})
		.mouseout(function(e){
			
			if( $(this).attr('id') != 'presentation.php'){
            	$(this).stop().animate({backgroundPosition:"(-20 -1)"}, {duration:200})
            }
			
		})
		.click(function(e){
			$(this).removeClass('passive');
            $(this).addClass('active');
            
            
            location.href = $(e.target).attr('id');
          

		})

	$('.active')
		.css( {backgroundPosition: "-200 0"} )
		.stop().animate({backgroundPosition:"(-200 0px)"}, {duration:5})
		
		
});