Sticky/parallax

Dear fellow Beaver Builder Users,

I need your help as I’m not able to figure out some design issue.

I’d like to implement the same effect on the H1 on my site as on the following one :

When you scroll down, the text remains centered vertically and a transformation occurs as it shortens to fit the shrinking section.

Is that CSS or JS or, I guess, both?

I tried some CSS tricks with position:sticky property but it does not work. I might apply it to the wrong element.

I thank you in advance for your help.

Nicolas