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HTML 

              
                <p>Hover over the panels to see the effects :) 
<div class="panels">
	<a class="panel p0" href="#">
		<div class="panel-info">
			<h1>Rainbow.</h1> 
			Bouncing <code>transition</code> on 
			<code>background-size</code> and 
			<code>background-position</code>.
		</div>
	</a>
	<a class="panel p1" href="#">
		<div class="panel-info">
			<h1>Sharp waves.</h1> Linear <code>transition</code> on 
			<code>background-position</code>.
		</div>
	</a>
	<a class="panel p2" href="#">
		<div class="panel-info">
			<h1>Soft discs.</h1> 
			Bouncing <code>transition</code> on 
			<code>background-position</code> and 
			<code>background-size</code>.
		</div>
	</a>
	<a class="panel p3" href="#">
		<div class="panel-info">
			<h1>White to...</h1> 
			Actually just a <code>transition</code> on the 
			<code>background-color</code> underneath the partially 
			transparent <code>linear-gradient</code>.
		</div>
	</a>
	<a class="panel p4" href="#">
		<div class="panel-info">
			<h1>Crash into Jupiter.</h1> 
			Just a <code>transition</code> on 
			<code>background-size</code> 
			(scaling, aspect ratio preserved).
		</div>
	</a>
	<a class="panel p5" href="#">
		<div class="panel-info">
			<h1>Stripes to ropes.</h1> 
			Another <code>transition</code> on 
			<code>background-size</code> 
			(distortion, aspect ratio not preserved).
		</div>
	</a>
	<a class="panel p6" href="#">
		<div class="panel-info">
			<h1>Stretched rainbow.</h1>
			Bouncing <code>transition</code> on 
			<code>background-position</code>.
		</div>
	</a>
	<a class="panel p7" href="#">
		<div class="panel-info">
			<h1>T-Rex teeth.</h1>
			Bouncing <code>transition</code> on 
			<code>background-size</code>.
		</div>
	</a>
	<a class="panel p8" href="#">
		<div class="panel-info">
			<h1>Happy sine wave.</h1>
			Another <code>transition</code> on 
			<code>background-position</code>.
		</div>
	</a>
	<a class="panel p9" href="#">
		<div class="panel-info">
			<h1>Make a tablecloth.</h1>
			Yet another <code>transition</code> on 
			<code>background-position</code>.
		</div>
	</a>
	<a class="panel p10" href="#">
		<div class="panel-info">
			<h1>Bar chart.</h1>
			Linear <code>transition</code> on both
			<code>background-position</code> and 
			<code>background-size</code>.
		</div>
	</a>
	<a class="panel p11" href="#">
		<div class="panel-info">
			<h1>Particles.</h1>
			Bouncing <code>transition</code> on 
			<code>background-position</code>.
		</div>
	</a>
	<a class="panel p12" href="#">
		<div class="panel-info">
			<h1>Horizontal bar chart.</h1>
			Again <code>transition</code> on both
			<code>background-position</code> and 
			<code>background-size</code>.
		</div>
	</a>
	<a class="panel p13" href="#">
		<div class="panel-info">
			<h1>Changing angle.</h1>
			Simulated using a bouncing <code>transition</code> on 
			<code>background-size</code>.
		</div>
	</a>
</div>
!

CSS 

              
                body {
	font-family: Helvetica;
	font-size: 15px;
}
h1 {
	margin: 0 0 8px;
	border-bottom: solid 1px white;
	font-size: 23px;
	font-style: italic;
}
code {
	color: deeppink;
	font-size: 17px;
}
.panel {
	width: 195px;
	height: 130px;
	margin: 0 -1px 0 0;
	border: solid 2px lightblue;
	border-radius: 13px;
	display: inline-block;
	overflow: hidden;
	text-decoration: none;
}
.panel-info {
	bottom: 0;
	right: 0;
	left: 0;
	padding: 8px 7px 19px;
	display: none;
	position: fixed;
	background: #222;
	color: white;
	content: attr(data-inf);
}
.panel:hover .panel-info {
	display: block;
}
 
.p0 {
	background: linear-gradient(90deg, 
			hsl(0, 100%, 80%) 0%, hsl(35, 100%, 80%) 10%, 
			hsl(71, 100%, 80%) 20%, hsl(107, 100%, 80%) 30%, 
			hsl(143, 100%, 80%) 40%, hsl(179, 100%, 80%) 50%, 
			hsl(215, 100%, 80%) 60%, hsl(251, 100%, 80%) 70%, 
			hsl(287, 100%, 80%) 80%, hsl(323, 100%, 80%) 90%, 
			hsl(359, 100%, 80%) 100%);
	background-size: 50% 1px;
	background-position: 0 0;
	transition: 3s cubic-bezier(0, 3.5, 1, -2.5);
}
.p0:hover {
	background-size: 100% 1px;
	background-position: -98px 0;
}
.p1 {
	background: linear-gradient(-45deg, transparent 65%, midnightblue  65%) 
			-13px 0,
		linear-gradient(45deg, transparent 65%, midnightblue  65%) 
			-13px 0,
		linear-gradient(-45deg, midnightblue  35%, transparent 35%),
		linear-gradient(45deg, midnightblue  35%, greenyellow 35%);
	background-size: 26px 26px;
	transition: 2s linear;
}
.p1:hover {
	background-position: 182px 0, 182px 0, 195px 0, 195px 0;
}
.p2 {
	background: radial-gradient(hotpink, white 70%) no-repeat 0 50%, 
		radial-gradient(gold, white 70%) no-repeat 50% 100%, 
		radial-gradient(greenyellow, white 70%) no-repeat 100% 50%, 
		radial-gradient(aqua, white 70%) no-repeat 50% 0;
	background-size: 35px 35px;
	transition: 3s cubic-bezier(0, 3.5, 1, -2.5);
}
.p2:hover {
	background-position: 0 0, 0 100%, 100% 100%, 100% 0;
	background-size: 25px 25px;
}
 
.p3 {
	background: linear-gradient(90deg, white, transparent);
	background-color: darkorange;
	transition: 4s ease-in-out;
}
.p3:hover {
	background-color: indigo;
}
.p4 {
	background: radial-gradient(transparent 61%, black 65%) 
			no-repeat center, 
		radial-gradient(circle at 0% 0%,
				rgb(123, 109, 100)  5%, rgb(182, 156, 132) 10%, 
				rgb(182, 156, 132) 15%, rgb(182, 156, 132) 20%, 
				rgb(196, 209, 228) 25%, rgb(197, 181, 155) 30%, 
				rgb(149, 133, 119) 35%, rgb(171, 168, 175) 40%, 
				rgb(165, 134, 116) 45%, rgb(182, 156, 132) 50%, 
				rgb(233, 232, 218) 55%, rgb(172, 150, 127) 60%, 
				rgb(154, 113,  81) 65%, rgb(214, 231, 232) 70%, 
				rgb(150, 138, 121) 75%, rgb(178, 164, 169) 80%, 
				rgb(173, 154, 144) 85%, rgb(179, 171, 160) 90%, 
				rgb(143, 127, 112) 95%, rgb(101,  95,  87) 100%) 
			no-repeat center;
	background-color: black;
	background-size: 26px 26px;
	transition: all 3s ease-in;
}
.p4:hover {
	background-size: 295px 295px;
}
.p5 {
	background: linear-gradient(45deg, slateblue 20%, transparent 25%, 
			transparent 75%, slateblue 80%), 
		linear-gradient(-45deg, slateblue 20%, transparent 25%, 
			transparent 75%, slateblue 80%);
	background-color: plum;
	background-size: 10px 1px;
	transition: all 1s ease-out;
}
.p5:hover {
	background-size: 5px 20px;
}
 
/* THIRD ROW */
.p6 {
	background: linear-gradient(hsl(0, 100%, 80%) 0%, hsl(35, 100%, 80%) 10%, 
			hsl(71, 100%, 80%) 20%, hsl(107, 100%, 80%) 30%, 
			hsl(143, 100%, 80%) 40%, hsl(179, 100%, 80%) 50%, 
			hsl(215, 100%, 80%) 60%, hsl(251, 100%, 80%) 70%, 
			hsl(287, 100%, 80%) 80%, hsl(323, 100%, 80%) 90%, 
			hsl(359, 100%, 80%) 100%);
	background-size: 1px 390px;
	background-position: 0 0;
	transition: 4s cubic-bezier(0, 2, 1, -1);
}
.p6:hover {
	background-position: 0 100%;
}
.p7 {
	background: linear-gradient(-45deg, transparent 67%, seashell 67%) 
			-13px 50%,
		linear-gradient(45deg, transparent 67%, seashell 67%) 
			-13px 50%,
		linear-gradient(-45deg, seashell 33%, transparent 33%) 0 50%,
		seashell linear-gradient(45deg, seashell 33%, saddlebrown 33%) 0 50%;
	background-repeat: repeat-x;
	background-size: 26px 26px;
	transition: 3.5s cubic-bezier(0, 3, 1, -2);
}
.p7:hover {
	background-size: 26px 260px;
}
.p8 {
	background: radial-gradient(hsl(359, 100%, 80%) 20%, black 70%) -10% 80%, 
		radial-gradient(hsl(0, 100%, 80%) 20%, black 70%) 0 50%, 
		radial-gradient(hsl(35, 100%, 80%) 20%, black 70%) 10% 20%, 
		radial-gradient(hsl(71, 100%, 80%) 20%, black 70%) 25% 0, 
		radial-gradient(hsl(107, 100%, 80%) 20%, black 70%) 40% 20%, 
		radial-gradient(hsl(143, 100%, 80%) 20%, black 70%) 50% 50%, 
		radial-gradient(hsl(179, 100%, 80%) 20%, black 70%) 60% 80%, 
		radial-gradient(hsl(215, 100%, 80%) 20%, black 70%) 75% 100%, 
		radial-gradient(hsl(251, 100%, 80%) 20%, black 70%) 90% 80%, 
		radial-gradient(hsl(287, 100%, 80%) 20%, black 70%) 100% 50%, 
		radial-gradient(hsl(323, 100%, 80%) 20%, black 70%) 110% 20%, 
		radial-gradient(hsl(359, 100%, 80%) 20%, black 70%) 125% 0;
	background-color: black;
	background-repeat: no-repeat;
	background-size: 26px 26px;
	transition: .3s cubic-bezier(0, 0.25, 1, .75);
}
.p8:hover {
	background-position: -25% 100%, -10% 80%, 0 50%, 10% 20%, 25% 0, 40% 20%, 
		50% 50%, 60% 80%, 75% 100%, 90% 80%, 100% 50%, 110% 20%;
}
.p9 {
	background: linear-gradient(90deg, darkcyan 37%, transparent 47%) 
			repeat-x -3px 128px, 
		linear-gradient(darkcyan 37%, transparent 47%) repeat-y 193px -3px;
	background-size: 13px 135px, 200px 13px;
	transition: .5s ease;
}
.p9:hover {
	background-position: -3px 0, 0 -3px;
}
.p10 {
	background: linear-gradient(transparent 49%, black 49%, 
				black 51%, transparent 51%) repeat-x 0 40px, 
		linear-gradient(deeppink, white) no-repeat 26px 49%,
		linear-gradient(gold, white) no-repeat 65px 49%,
		linear-gradient(lemonchiffon, greenyellow) no-repeat 104px 50%,
		linear-gradient(aqua, white) no-repeat 143px 49%;
	background-color: indigo;
	background-size: 1px 50px, 26px 1px, 26px 1px, 26px 1px, 26px 1px;
	transition: .2s linear;
}
.p10:hover {
	background-position: 0 40px, 26px 37%, 65px 17%, 104px 55%, 143px 29%;
	background-size: 1px 50px, 26px 26px, 26px 52px, 26px 13px, 26px 39px;
}
.p11 {
	background: radial-gradient(deeppink, transparent 16px) 20% 100%, 
		radial-gradient(gold, transparent 16px) 40% 100%, 
		radial-gradient(greenyellow, transparent 16px) 60% 100%, 
		radial-gradient(aqua, transparent 16px) 80% 100%;
	background-repeat: no-repeat;
	background-size: 26px 26px;
	background-color: black;
	transition: 2.5s cubic-bezier(0, 3.25, 1, -2.25);
}
.p11:hover {
	background-position: 100% 0, 75% 50%, 25% 0, 0 50%;
}
.p12 {
	background: linear-gradient(90deg, lightblue, deeppink) 0 15%, 
		linear-gradient(90deg, lightblue, gold) 0 50%,
		linear-gradient(90deg, lightblue, greenyellow) 0 85%,
		linear-gradient(lemonchiffon, orchid) 0 0;
	background-repeat: no-repeat;
	background-size: 91px 26px, 78px 26px, 156px 26px, 195px 195px;
	transition: background-size .85s cubic-bezier(0, .35, 1, .65), 
		background-position 1.25s .5s ease-in-out;
}
.p12:hover {
	background-position: -5px 15%, -5px 50%, -5px 85%, 0 -65px;
	background-size: 1px 26px, 1px 26px, 1px 26px, 195px 195px;
}
.p13 {
	background: -webkit-linear-gradient(left top, orangered 49%, lemonchiffon 51%)
			50% 50%;
  background: linear-gradient(to right bottom, orangered 49%, lemonchiffon 51%)
			50% 50%;
	background-size: 195px 156px;
	transition: 2.75s cubic-bezier(0, 3.25, 1, -2.25);
}
.p13:hover {
	background-size: 195px 390px;
}
!

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