Fixed Position but relative to A container

Hey, I am trying to add a button on the top which works exactly like the “Fixed” positioning in Webflow but its position is relative to a certain container and not the body.

Here’s an example:
The pitch button on this website https://www.3one4capital.com/

I’d love it if someone could help me with a tutorial to fix this. Thanks a lot!


Here is my site Read-Only: LINK
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