animate.css/source/rotating_entrances/rotateInDownLeft.css

@keyframes rotateInDownLeft {
	0% {
		transform-origin: left bottom;
		transform: rotate(-90deg);
		opacity: 0;
	}

	100% {
		transform-origin: left bottom;
		transform: rotate(0);
		opacity: 1;
	}
}

.rotateInDownLeft {
	animation-name: rotateInDownLeft;
}