BUTTON 20

/* HTML */
<a href="#"><button class="button-20">Download</button></a>

/* CSS */
.button-20
{
	display: block;
	font-size: 1.1em;
	font-weight: bold;
	text-transform: uppercase;
	padding: 10px 15px;
	margin: 20px auto;
	color: #ccc;
	background-color: #555;
	background: -webkit-linear-gradient(#888, #555);
	background: linear-gradient(#888, #555);
	border: 0 none;
	border-radius: 3px;
	text-shadow: 0 -1px 0 #000;
	box-shadow: 0 1px 0 #666, 0 5px 0 #444, 0 6px 6px rgba(0,0,0,0.6);
	cursor: pointer;
	-webkit-transition: all 150ms ease;
	transition: all 150ms ease;
}

.button-20:hover, 
.button-20:focus
{
	-webkit-animation: pulsate 1.2s linear infinite;
	animation: pulsate 1.2s linear infinite;
}
	
@-webkit-keyframes pulsate
{
	0%   { color: #ddd; text-shadow: 0 -1px 0 #000; }
	50%  { color: #fff; text-shadow: 0 -1px 0 #444, 0 0 5px #ffd, 0 0 8px #fff; }
	100% { color: #ddd; text-shadow: 0 -1px 0 #000; }
}
		
@keyframes pulsate
{
	0%   { color: #ddd; text-shadow: 0 -1px 0 #000; }
	50%  { color: #fff; text-shadow: 0 -1px 0 #444, 0 0 5px #ffd, 0 0 8px #fff; }
	100% { color: #ddd; text-shadow: 0 -1px 0 #000; }
}

.button-20:active
{
	color: #fff;
	text-shadow: 0 -1px 0 #444, 0 0 5px #ffd, 0 0 8px #fff;
	box-shadow: 0 1px 0 #666, 0 2px 0 #444, 0 2px 2px rgba(0,0,0,0.9);
	-webkit-transform: translateY(3px);
	transform: translateY(3px);
	-webkit-animation: none;
	animation: none;
}