How can I prevent the browser from scrolling by keyboard input?

To prevent the browser from scrolling when the player clicks the arrow buttons, Add the following script to the body attribute in your index.html file: 

<script>
window.addEventListener("keydown", function(e) {
// space and arrow keys
if([32, 37, 38, 39, 40].indexOf(e.keyCode) > -1) {
e.preventDefault();
}
}, false);
</script>