@keyframes vertical-flip {
	0%		{transform: rotateX(0deg);}
	25%		{transform: rotateX(0deg);}
	50%		{transform: rotateX(180deg);}
	75%		{transform: rotateX(0deg);}
	100%	{transform: rotateX(0deg);}
}

.vertical-flip {
	animation-name: vertical-flip;
	animation-duration: 4s;
	animation-iteration-count: infinite;
}