animate.css/source/swing.css

@-webkit-keyframes swing {
	20%, 40%, 60%, 80%, 100% { -webkit-transform-origin: top center; }
	20% { -webkit-transform: rotate(15deg); }	
	40% { -webkit-transform: rotate(-10deg); }
	60% { -webkit-transform: rotate(5deg); }	
	80% { -webkit-transform: rotate(-5deg); }	
	100% { -webkit-transform: rotate(0deg); }
}

@-moz-keyframes swing {
	20% { -moz-transform: rotate(15deg); }	
	40% { -moz-transform: rotate(-10deg); }
	60% { -moz-transform: rotate(5deg); }	
	80% { -moz-transform: rotate(-5deg); }	
	100% { -moz-transform: rotate(0deg); }
}

@-o-keyframes swing {
	20% { -o-transform: rotate(15deg); }	
	40% { -o-transform: rotate(-10deg); }
	60% { -o-transform: rotate(5deg); }	
	80% { -o-transform: rotate(-5deg); }	
	100% { -o-transform: rotate(0deg); }
}

@keyframes swing {
	20% { transform: rotate(15deg); }	
	40% { transform: rotate(-10deg); }
	60% { transform: rotate(5deg); }	
	80% { transform: rotate(-5deg); }	
	100% { transform: rotate(0deg); }
}

.swing {
	-webkit-transform-origin: top center;
	-moz-transform-origin: top center;
	-o-transform-origin: top center;
	transform-origin: top center;
	-webkit-animation-name: swing;
	-moz-animation-name: swing;
	-o-animation-name: swing;
	animation-name: swing;
}