Blend mode Navbar

Hi all,

I’m looking for a way to create the same Navbar as in this example; https://verveagency.com/
When the Navbar goes over other elements (pictures especially) the blending mode changes automatically to (I guess) Difference. In other topics I see you have to do something with Embed and , but I can’t figure it out on my website. When I change (for example) link to Blending Mode Difference nothing happens.

Attached a link to my current website; Webflow - Jochem.studio