body{
	text-align: center;
	perspective: 500px;
	perspective-origin: 50% 90%;
}

#principal {
display: block;
width: 500px;
margin: 50px auto;
padding: 15px;
border: 1px solid #666666;
background: #CCCCCC;
transition: transform 1s ease-in-out 0.1s;
}

#principal:hover {
	transform: perspective(500px) rotate3d(0, 1, 0, 360deg)
}

#titulo {
	font: bold 36px verdana, sans-serif;
}