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                <h3>Loading videos based on screen sizes</h3>
<p>Chrome doesn't support inline media queries for the source in a <code>video</code> tag like the <code>picture</code> element. Sometimes you want to load a different video based on the screen size, such as a different aspect ratio. This is a simple script to accomplish this. It could easily be extended to a resize event. </p>
<div id="video">
	<video id="bgvid" preload="auto" autoplay="" loop="" muted="" playsinline="" class="" data-desktop-vid="" 
<h3>Inverse to demo multiple vids</h3>
<div id="video">

	<video id="bgvid" preload="auto" autoplay="" loop="" muted="" playsinline="" class="" data-mobile-vid="" 
		data-desktop-vid="" >


                // basics

body {
	padding: 10px; 
	font-family: system, -apple-system, ".SFNSText-Regular", "San Francisco", "Roboto", "Segoe UI", "Helvetica Neue", "Lucida Grande", sans-serif;
	font-weight: 300;

video {
	max-width: 100%;
code {
	color: darkred;


//get all vids
var video =  document.querySelectorAll('video')

//add source to video tag
function addSourceToVideo(element, src) {
    var source = document.createElement('source');
    source.src = src;
    source.type = 'video/mp4';

//determine screen size and select mobile or desktop vid
function whichSizeVideo(element, src) {
	var windowWidth = window.innerWidth ? window.innerWidth : $(window).width();
	if (windowWidth > 1200 ) {
		addSourceToVideo( element, src.dataset.desktopVid);
	} else {
		addSourceToVideo(element, src.dataset.mobileVid);

//init only if page has videos
function videoSize() {
	if (video !== undefined) {
	video.forEach(function(element, index) {
				element, //element
				element  //src locations

//note IE11 polyfill needed for each, convert to for loop.