smoothscroll.min.js

(function(root,smoothScroll){"use strict";if(typeof define==="function"&&define.amd){define(smoothScroll)}else if(typeof exports==="object"&&typeof module==="object"){module.exports=smoothScroll()}else{root.smoothScroll=smoothScroll()}})(this,function(){"use strict";if(typeof window!=="object")return;if(document.querySelectorAll===void 0||window.pageYOffset===void 0||history.pushState===void 0){return}var getTop=function(element,start){if(element.nodeName==="HTML")return-start;return element.getBoundingClientRect().top+start};var easeInOutCubic=function(t){return t<.5?4*t*t*t:(t-1)*(2*t-2)*(2*t-2)+1};var position=function(start,end,elapsed,duration){if(elapsed>duration)return end;return start+(end-start)*easeInOutCubic(elapsed/duration)};var smoothScroll=function(el,duration,callback,context){duration=duration||500;context=context||window;var start=context.scrollTop||window.pageYOffset;if(typeof el==="number"){var end=parseInt(el)}else{var end=getTop(el,start)}var clock=Date.now();var requestAnimationFrame=window.requestAnimationFrame||window.mozRequestAnimationFrame||window.webkitRequestAnimationFrame||function(fn){window.setTimeout(fn,15)};var step=function(){var elapsed=Date.now()-clock;if(context!==window){context.scrollTop=position(start,end,elapsed,duration)}else{window.scroll(0,position(start,end,elapsed,duration))}if(elapsed>duration){if(typeof callback==="function"){callback(el)}}else{requestAnimationFrame(step)}};step()};var linkHandler=function(ev){if(!ev.defaultPrevented){ev.preventDefault();if(location.hash!==this.hash)window.history.pushState(null,null,this.hash);var node=document.getElementById(this.hash.substring(1));if(!node)return;smoothScroll(node,500,function(el){location.replace("#"+el.id)})}};document.addEventListener("DOMContentLoaded",function(){var internal=document.querySelectorAll('a[href^="#"]:not([href="#"])'),a;for(var i=internal.length;a=internal[--i];){a.addEventListener("click",linkHandler,false)}});return smoothScroll});