I heard quite a lot of Carrd folks wanted this to make the navigation menu of their site more mobile friendly. So what this navbar plugin does is that it's a normal navbar on desktop, but collapses into a hamburger menu on mobile.
I just launched it, so it's available at $19 $15 now. Just a 1-off payment and use forever, no recurring bs.
Demo:
https://navbar.carrd.co/
Home:
https://plugins.carrd.co