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HTML

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Insecure Resource

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CSS

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CSS preprocessors help make authoring CSS easier. All of them offer things like variables and mixins to provide convenient abstractions.

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CSS Base

About CSS Base

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JavaScript

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Babel includes JSX processing.

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HTML 

              
                <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="https://iconaircraft.s3.amazonaws.com/ICON_Web+4.0_Loop_16x9_DRAFT190723_26sec+3700.mp4" 
		data-mobile-vid="https://iconaircraft.s3.amazonaws.com/ICON_Web+4.0_Loop_1x1_DRAFT190723_26sec-mobile.mp4">
	</video>
</div>
		
		
		
<h3>Inverse to demo multiple vids</h3>
<div id="video">

	<video id="bgvid" preload="auto" autoplay="" loop="" muted="" playsinline="" class="" data-mobile-vid="https://iconaircraft.s3.amazonaws.com/ICON_Web+4.0_Loop_16x9_DRAFT190723_26sec+3700.mp4" 
		data-desktop-vid="https://iconaircraft.s3.amazonaws.com/ICON_Web+4.0_Loop_1x1_DRAFT190723_26sec-mobile.mp4" >
	</video>
</div>
!

CSS 

              
                // 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;
}
!

JS 

              
                
//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';
	console.log(src);
    element.appendChild(source);
	
}

//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) {
			whichSizeVideo(  
				element, //element
				element  //src locations
			);	
		});
	}
}
videoSize();


//note IE11 polyfill needed for each, convert to for loop.
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999px

Console