wheelzoom.js
function draggable(e) {
			e.preventDefault();
			previousEvent = e;
			document.addEventListener('mousemove', drag);
			document.addEventListener('mouseup', removeDrag);
		}
function draggable(e) {
			e.preventDefault();
			previousEvent = e;
			document.addEventListener('mousemove', drag);
			document.addEventListener('mouseup', removeDrag);
		}
function draggable ( e ) { e . preventDefault ( ) ; previousEvent = e ; document . addEventListener ( 'mousemove' , drag ) ; document . addEventListener ( 'mouseup' , removeDrag ) ; }
Make the background draggable
Make the background draggable