SVG Key Frame css

by Rayudu Ikkurthi

HTML

<h1>Like/Heart Animation in Pure CSS</h1>
<input type="checkbox" id="like"/>
<label for="like">
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24">
    <path d="M12 21.35l-1.45-1.32c-5.15-4.67-8.55-7.75-8.55-11.53 0-3.08 2.42-5.5 5.5-5.5 1.74 0 3.41.81 4.5 2.09 1.09-1.28 2.76-2.09 4.5-2.09 3.08 0 5.5 2.42 5.5 5.5 0 3.78-3.4 6.86-8.55 11.54l-1.45 1.31z"/>
</svg>
</label>

<p class="copyright">
	<span>Pen Developed by <a href="http://codepen.io/Himateja" target="_blank">Himateja</a>| <a href="http://twitter.com/Himateja143" target="_blank">@Himateja143</a> | <a href="http://jamesb.in" target="_blank">Go to James.bin</a></span>
</p>

CSS

/*
Author : Himateja
Editor : Codepen
Permissions : Open Source
*/
*
{
	margin: 0;
	padding: 0;
	-webkit-font-smoothing: antialiased;
	-webkit-tap-highlight-color: transparent;
	-webkit-user-select:none;
	box-sizing: border-box;
}

html, body 
{
  overflow: hidden;
  height: 100%;
  zoom: reset;
  background: white;
  font-family: Montserrat;
}

h1 {
	text-align: center;
	margin-top: 75px;
}

input[type=checkbox] {
	clear: both;
	display: none;
}

input[type="checkbox"] {
  display: none;
}

input[type="checkbox"] + label {
	position: absolute;
	z-index: 100;
	overflow: hidden;
	height: 6em;
	width: 6em;
	left: calc(50% - 3em);
	top: calc(50% - 3em);
	display: block;
	text-align: center;
	line-height: 95px;
	cursor: pointer;
	-webkit-transition: all 300ms ease;
	transition: all 300ms ease;
	border-radius: 50%;
	background-color: #fff;
}

input[type="checkbox"] + label:before {
	content: '';
	z-index: -1;
	position: absolute;
	background: rgb(220, 72, 127);
	width: 100%;
	height: 100%;
	border-radius: 50%;
	top: 0;
	left: 0;
	transform: scale(0);
	-webkit-ransform: scale(0);
}

input[type="checkbox"] + label:after {
	content: '';
	z-index: -1;
	position: absolute;
	background: white;
	width: 100%;
	height: 100%;
	border-radius: 50%;
	top: 0;
	left: 0;
	transform: scale(0);
	-webkit-transform: scale(0);
}

input[type="checkbox"]:checked + label svg {
	-webkit-transition: all 300ms ease-in-out;
	transition: all 300ms ease-in-out;
	fill: rgb(220, 72, 127);
	transform: scale(1.3);
	-webkit-transform: scale(1.3);
}

input[type="checkbox"]:checked + label:after {
	-webkit-animation: like-a 0.3s 0.2s forwards;
	-moz-animation: like-a 0.3s 0.2s forwards;
	animation: like-a 0.3s 0.2s forwards;
}

input[type="checkbox"]:checked + label:before {
	-webkit-animation: like-a 0.5s 0s forwards;
	-moz-animation: like-a 0.5s 0s forwards;
	animation: like-a 0.5s 0s forwards;
}

label svg {
	display: inline-flex;
	vertical-align: middle;
	width: 35px;
	fill: rgb(167, 167,...