i wanted to know how to remove that image animation when

Hey i wanted to know how to remove that image animation when a user presses the send button. I've tried to contact the developer and the told me one fix that din't really work and told me some CSS code which i'm not quite sure where to place it.

http://www.wearepixel8.com/tips-and-tutorials/customize-contact-form-7/#comment-791

Thanks in advance!