Stare at it. Doesn't it look like the little rectangles are moving? You can look inside, this is changing color.
Me and https://www.google.com/search?q=rainbow+colors+in+order+blended&tbm=isch&ved=2ahUKEwivi6CtmbP1AhUhIn0KHcX6Aw8Q2-cCegQIABAA&oq=rainbow+colors+in+order+blended&gs_lcp=CgNpbWcQAzoHCAAQsQMQQzoECAAQQzoFCAAQgAQ6BAgAEB46BggAEAgQHlDGU1iCgwFgpIYBaAFwAHgAgAGqAYgB8AqSAQMwLjmYAQCgAQGqAQtnd3Mtd2l6LWltZ8ABAQ&sclient=img&ei=5XLiYe-EBaHE9APF9Y94&bih=876&biw=1600&surl=1&safe=active&ssui=on#imgrc=pdz9j7eYRBSq3M
