Cool visual illusion. It may be difficult to make the mental switch at first, but it is quite intriguing.
If you look at the spinning girl’s silhouette below, you will think it is spinning clockwise, probably. When you check her shadow below, momentarily the spinning direction changes in your mind, and now the girl is spinning counter-clockwise. It can be quite hard at the beginning to notice switch of the spinning direction, but eventually you’ll manage.