smooth-scrolling.js

	var $window = $(window);		//Window object
	
	var scrollTime = 1.2;			//Scroll time
	var scrollDistance = 270;		//Distance. Use smaller value for shorter scroll and greater value for longer scroll
		
	$window.on("mousewheel DOMMouseScroll", function(event){
		
		event.preventDefault();	
										
		var delta = event.originalEvent.wheelDelta/120 || -event.originalEvent.detail/3;
		var scrollTop = $window.scrollTop();
		var finalScroll = scrollTop - parseInt(delta*scrollDistance);
			
		TweenMax.to($window, scrollTime, {
			scrollTo : { y: finalScroll, autoKill:true },
				ease: Power2.easeOut,
				autoKill: true,
				overwrite: 5							
			});
					
	});

	$window.on('keydown', function(e) {
		var finalScroll = 0;
		//down
		if (e.keyCode == 40) {
			e.preventDefault(); //prevent default arrow key behavior
		    finalScroll = $window.height()/1.5;
		}
		//up
		else if (e.keyCode == 38) {
			e.preventDefault(); //prevent default arrow key behavior
		    finalScroll = -$window.height()/1.5;
		}

		//scroll element into view    
		TweenMax.to($window, 0.5, {
			scrollTo : { y: '+='+finalScroll },
				ease: Power2.easeOut					
			});
	});