Implementing full-screen scrolling to execute once every time you turn to this screen_html/css_WEB-ITnose

I found a demo of full-screen scrolling on the Internet, and then made animations in each screen (basic image displacement, visible, hidden, gradient)
But these actions only happen once
I want to ask for advice on how to achieve repeatable every time At which screen can the animation effect be executed again

Reply to the discussion (solution)

Please help me make a page like this

Where is the jQuery master?

Image displacement, visible and hidden gradients, etc. can be realized with CSS3 animation. . . .