How to create a parallax effect?

Question

css

Hello!
There is a similar animation of expanding and collapsing blocks:

Is it implemented by adding classes with the css keyframes animation property or do animation through js?

Answer 1

Here you will need both. A very complex example, I completely agree.
Here it will probably be quite painful to do without vue/react/angular.
Although this effect is not original - look, perhaps something similar has been implemented and there is some kind of library. There is a site unheap, look there.

Answer 2

I did not see any extreme difficulties. The most difficult thing here is to calibrate the darg&drop, that's all. The rest are simple transitions, nothing complicated. No need to look at the wow effect with your mouth open, look at what happens to the blocks. Ordinary state change by adding classes.