Header drop shadow hidden behind page content

Hey! I've used your css example to add a drop shadow on my header, and it works like a charm. But i have a fullwidth section created by elementor as the first thing on my page, and when i remove the page padding so the full width section starts right after the header, the drop shadow is being rendered behind the full width section. How come? And what can i do so that the header is "top layer".

Thanks!