Streaming live at 10am (PST)

Webflow Content Lock

In the project I have a section which houses an article
And there is a div block positioned as fixed

How to disable scrolling of the article when the fixed div block is active? It is kind of a Content Lock for the article.
Like this :

I can make the fixed div block appear/disappear using memberstack.

Here is my site Read-Only: LINK
(how to share your site Read-Only link)