The problem with this: if you reduce the width of your browser. You will see that your Elementor header resizes and the height changes. Which means the position of the sticky navigation would need to change, and for that i do not have a soluton as it would require Javascript to recalc it – which isn’t good.
You may want to reconsider the sticky header, as this is another issue:
That image is from a screen preview taken from one of the most common size laptop screens ( 1366 x 768px ) – and that header and nav is taking up around 1/3rd of the viewport… and that without any Operating System UI in there. It doesn’t leave a lot of screen space for those users.