$(document).ready(function() {	



$('#back').click(function(){
	
	if(itemNumber === 1){
		
			$('.contentList').animate({'marginLeft':'0'});
			
			
		}else if(itemNumber<=totalItems){
			
			
			$('.contentList').animate({'marginLeft':'+=960'});
		
			itemNumber -= 1;
			
			}
	
	clearInterval(listItem);
	
	});
	
	
$('#next').click(function(){
	
	if(itemNumber<totalItems){
		
		$('.contentList').animate({'marginLeft':'-=960'});
		
		itemNumber += 1;
		
		
		}else if(itemNumber===totalItems){
			
			$('.contentList').animate({'marginLeft':'0'});
			
			itemNumber = 1;
			
			
			}
	
	clearInterval(listItem);
	
	});	


  
  var itemNumber = 1;
  
  var totalItems = $('.contenido').length;
  
  var timer = 10000; 
  
			
			var listItem = setInterval(function(){	
			
			  
			 
			 if(itemNumber<totalItems){
				 
				 $('.contentList').animate({'marginLeft':'-=960'});
				 	
				 itemNumber += 1;
				 
				 
				 }else if(itemNumber>=totalItems){
					 
					 $('.contentList').animate({'marginLeft':'0'});
					 
					 itemNumber = 1;
					 
					 
					 }		 
			 
			}, timer);
		
		
	listItem;	
	
	
	});