How do i create a Div that is 100% width & height that cannot be scrolled on. However, with a button click that goes to the "next view" which is top:100%; (out of sight) I want the second portion of the website to be scrollable. Sort of like a front-page you could say.

What i'm looking for is more or less a JS that disables scrolling on a portion of the website.

ex of what I want is used on: <https://mega.co.nz/>. the scrollbars have disappeard on the "front-page"