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HTML

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About the <head>

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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 

              
                <header>
 <div class="banner">
  <div class="img-1" style="background-image: url(https://unsplash.it/1280/640?image=1044);"></div>
  <div class="img-2" style="background-image: url(https://unsplash.it/1280/640?image=1033);"></div>
  <div class="img-3" style="background-image: url(https://unsplash.it/1280/640?image=1019);"></div>
  <div class="img-4" style="background-image: url(https://unsplash.it/1280/640?image=1000);"></div>
 </div>
</header>
<h1>CSS Looping Fader</h1>
<p>This is based on an example by <a href="https://snook.ca/archives/html_and_css/simplest-css-slideshow">Jonathan Snook</a>, but has been updated to fade seamlessly between images without cross fading (which reveals the background). This is achieved by animating the z-index while simultaneously delaying the fade out of each layer until the replacing layer is fully visible.</p>
<p>While the animation timeline does depend on a set number of images, it would be possible to set up classes for each variation (for example, 4, 5, and 6 image rotations). The total duration = (fade curation + visible duration) * number of images. More details can be found in the Jonathan Snook article linked above.</p>
<p>This version also uses CSS backgrounds (defined in the HTML by an assumed CMS) instead of IMG tags to provide a more seamless (and responsive, depending on your CSS setup) end result.</p>

<h1>Other animations</h1>
<p>Among any other animatable CSS effects, clipping path animations are pretty effective. However, this may take significantly more processing power (so watch your CPU!).</p>

<section>
 <div class="banner">
  <div class="img-1" style="background-image: url(https://unsplash.it/1280/640?image=993);"></div>
  <div class="img-2" style="background-image: url(https://unsplash.it/1280/640?image=221);"></div>
  <div class="img-3" style="background-image: url(https://unsplash.it/1280/640?image=984);"></div>
  <div class="img-4" style="background-image: url(https://unsplash.it/1280/640?image=651);"></div>
 </div>
</section>
!

CSS 

              
                html, body, div, span, applet, object, iframe,
h1, h2, h3, h4, h5, h6, p, blockquote, pre,
a, abbr, acronym, address, big, cite, code,
del, dfn, em, font, img, ins, kbd, q, s, samp,
small, strike, strong, sub, sup, tt, var,
dl, dt, dd, ol, ul, li,
fieldset, form, label, legend,
table, caption, tbody, tfoot, thead, tr, th, td {
	margin: 0;
	padding: 0;
	border: 0;
	outline: 0;
	font-weight: inherit;
	font-style: inherit;
	font-size: 100%;
	font-family: inherit;
	vertical-align: baseline;
}

body {
	line-height: 1;
	font-family: 'Avenir Next', 'Myriad', sans-serif;
	-webkit-font-smoothing: antialiased;
	text-align: center;
}

header, section, footer,
aside, nav, article, figure {
	display: block;
}

body {
	width: 100%;
	color: #767a7d;
	background-color: #1b2126;
}

header {
	width: 100%;
	height: 480px;
	margin: 0 0 40px 0;
	padding: 0;
}

a, a:visited {
	color: #a4a6a8;
	text-decoration: none;
	-webkit-transition: color 0.2s ease;
	-moz-transition: color 0.2s ease;
	-ms-transition: color 0.2s ease;
	-o-transition: color 0.2s ease;
	transition: color 0.2s ease;
}

a:hover, a:active {
	color: #d1d3d4;
	text-decoration: none;
}

a:focus {
	outline: none;
}

a.info, a.info:visited, a.info:hover, a.info:active, a.purchase, a.purchase:visited, a.purchase:hover, a.purchase:active {
	color: #ffffff;
	-webkit-transition: background-color 0.2s ease;
	-moz-transition: background-color 0.2s ease;
	-ms-transition: background-color 0.2s ease;
	-o-transition: background-color 0.2s ease;
	transition: background-color 0.2s ease;
}

a.info:hover, a.info:active, a.purchase:hover, a.purchase:active {
	background-color: #f2b90c;
}

h1, h2, h3, h4, h5, h6 {
	line-height: 1.5em;
	color: #ffffff;
}

h1 {
	font-size: 2em;
}

h2 {
	font-size: 3em;
	font-weight: 100;
}

h3 {
	font-size: 1.5em;
}

h4 {
	font-size: 1.3em;
}

p {
	width: 480px;
	margin: 2em auto;
}

/* Banner Backgrounds
/*---------------------------------------------*/

.banner {
	position: absolute;
	width: 100%;
	height: 480px;
}

.img-1, .img-2, .img-3, .img-4 {
	position: absolute;
	top: 0;
	width: 100%;
	height: 480px;
	background-size: cover;
	background-repeat: no-repeat;
	background-position: center;
	z-index: -18;
	opacity: 0;
	animation-name: fade;
	animation-duration: 16s;
	animation-iteration-count: infinite;
}

section .img-1, section .img-2, section .img-3, section .img-4 {
	opacity: 1;
	animation-name: iris;
	animation-duration: 16s;
	animation-iteration-count: infinite;
}

.img-1 { animation-delay: 0s; }
.img-2 { animation-delay: 4s; }
.img-3 { animation-delay: 8s; }
.img-4 { animation-delay: 12s; }

/* Banner Animations (4s per image, 16s total timeline)
/*---------------------------------------------*/

@keyframes crossfade {
	/* This is the default behaviour as described by Jonathan Snook*/
	00.00%	{ opacity: 0; }
	06.25%	{ opacity: 1; }
	25.00%	{ opacity: 1; }
	31.25%	{ opacity: 0; }
	100.0%	{ opacity: 0; }
}

@keyframes fade {
	/* By offsetting the fade out and animating z-index, we can prevent the background from showing up at all*/
	00.00%	{ opacity: 0; z-index: -10; }
	06.25%	{ opacity: 1; z-index: -10; }
	31.25%	{ opacity: 1; z-index: -12; }
	37.50%	{ opacity: 0; z-index: -14; }
	100.0%	{ opacity: 0; z-index: -16; }
}

/* Animating a clip-path in Google Chrome can destroy performance...it's crazy CPU intensive */
@keyframes iris {
	00.0%	{ clip-path: circle(0% at 50% 0%); z-index: -10; }
	12.5%	{ clip-path: circle(120% at 50% 0%); z-index: -10; }
	31.25%	{ clip-path: circle(120% at 50% 0%); z-index: -12; }
	37.50%	{ clip-path: circle(0% at 50% 0%); z-index: -14; }
	100%	{ clip-path: circle(0% at 50% 0%); z-index: -16; }
}
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JS
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