'use strict';(function($){$.fn.inertiaScroll=function(options){var settings=$.extend({parent:'',childDelta1:0.02,childDelta2:0.1,parentDelta:0.08},options);var $window=$(window);var $body=$('body');var $parent=settings.parent;var $child=this;var ChildBox=function(elm,offset,speed,margin){this.elm=elm;this.offset=offset!==undefined?offset:0;this.speed=speed!==undefined?speed:1;this.margin=margin!==undefined?margin:0};ChildBox.prototype.update=function(windowOffset,offsetBottom){this.offset+=(windowOffset*settings.childDelta1*Number(this.speed)-this.offset)*settings.childDelta2;this.elm.css({transform:'translate3d('+0+','+(Number(this.margin)-Number(this.offset))+'px ,'+0+')'})};var ParentBox=function(elm,offset,speed,margin){ChildBox.apply(this,arguments)};ParentBox.prototype=Object.create(ChildBox.prototype,{constructor:{value:ParentBox}});ParentBox.prototype.update=function(windowOffset){this.offset+=(windowOffset-this.offset)*settings.parentDelta;this.elm.css({transform:'translate3d('+0+','+(-this.offset)+'px ,'+0+')'})};ParentBox.prototype.setcss=function(){this.elm.css({'width':'100%','position':'fixed'})};var Boxes=function(){this.ChildBox=[];this.ChildBoxLength=0;this.ParentBox='';this.windowHeight=0};Boxes.prototype={init:function(){this.createElm($child,$parent);this.loop()},createElm:function(child,parent){this.ParentBox=new ParentBox(parent,0,1);this.ParentBox.setcss();this.boxArrayLength=child.length;for(var i=0;i<this.boxArrayLength;i++){var e=child.eq(i);var speed=e.data('speed');var margin=e.data('margin');this.ChildBox.push(new ChildBox(e,0,speed,margin))}},smoothScroll:function(){var windowOffset=$window.scrollTop();var offsetBottom=windowOffset+this.windowHeight;this.ParentBox.update(windowOffset);for(var i=0;i<this.boxArrayLength;i++){this.ChildBox[i].update(windowOffset,offsetBottom)}},loop:function(){this.smoothScroll();window.requestAnimationFrame(this.loop.bind(this))}};$(function(){$body.height($parent.height());var boxes=new Boxes();boxes.init()});return this}})(jQuery);