adding horizontal scrolling by mouse slide

index.html

@@ -258,6 +258,28 @@ h1{
 		}
 	}
 
+	var slider = {
+		startingPostition: 0,
+		slidingDistance: 0,
+		pagePosition: 0,
+		init: function(){
+			window.addEventListener('mousedown', function(event){
+				slider.startingPostition = event.clientX;
+				slider.pagePosition = window.pageXOffset;
+				window.addEventListener('mousemove', slider.slide);
+			});
+			window.addEventListener('mouseup', function(event){
+				window.removeEventListener('mousemove', slider.slide);
+			});
+		},
+		slide: function(event){
+			event.preventDefault()
+			slider.slidingDistance = slider.startingPostition - event.clientX;
+			window.scrollTo(slider.pagePosition + slider.slidingDistance, 0);
+		}
+	}
+
 	life.start();
+	slider.init();
 })();
 </script>