Mix-Blend-Mode Navbar is not working


I need some help with my blend mode navbar.
I tried also coding but it´s not working.

My name and menu button is in the background and should be placed in front.
I don´t know why it´s not working.

My idea ist to scroll over background and images and my navbar invert/differnece colour.

Here is my site Read-Only: Webflow - evafinkbeiner.com

Thanks a lot for your support.