Bubbles not moving(floating) while scrolling page

[TaRoshka]

I am working on some stuff. As you can see from the link http://logic.al/lufra/rreth-nesh/historiku

there are bubbles around the content. Those bubbles were supposed to move (float) up and down while scrolling the page. like here.: https://moz.com/about

Can anyone help me with this issue?

Thank you !