As in social networks organized block fixation?

Question

css

Facebook and VKontakte have a fixed header and menu (sidebar). When scrolling, only the part with the news scrolls. On Facebook, I never found how it was implemented (in styles, I don’t have styles like position: fixed;in VK - yes, but there, as far as I understand, the script itself is responsible for part of the robot).
If someone came across, knows how to implement this, where to look, maybe there is some kind of script? I searched everything I could but did not find the necessary information (or simply did not understand what to look for). I would be glad for any information! Thanks in advance for your reply :)

Answer 1

I searched everything I could, but I did not find the necessary information.

Strange, but I have a sea of ​​​​information on the first page on Google. Look . And here is the finished solution from this first page.