Issue with hamburge menu on tablets and below

On tablets and below the hamburger menu is not showing up n this site. It is enabled but not working for some reason and I cannot figure it out. Any advice? Here is the read only link:
Published link:

It would be helpful if you could share a published URL to the page so inspection in a browser is possible. This is something that is part of the posting guidelines.

oops. Thanks for the heads up. edited the post to include published link.