This is very easy and powerfull parallax-scroller plugin. It has based on Greensock animation system.
import EasyParallax from 'gsap-easyparallax';
var easyParallax = new EasyParallax({
mainContainer : '#site',
customScroll : true,
customScrollContainer : '#drag-container',
customScrollProgress : '.drag-elem',
customScrollBar : '.drag-bar',
pagingClass: '.paging',
animation: function() {
//GSAP Time Line Animation
}
});