Hi, I'm using Helix Ultimate 2.2.6 on Joomla 6 and I'd like to implement a transparent overlay header. What I want to achieve:

On page load: the header (logo + navigation) is fully transparent and visually overlaps the content below it – so the content starts at the very top of the viewport, directly behind the header On scroll: the header becomes a solid or semi-transparent sticky bar that stays fixed at the top

My question: What is the correct and recommended way to implement this in Helix Ultimate 2.2.x? Is there a built-in option, a specific predefined header style that supports this, or does it require custom CSS/JS? A working example or code snippet would be very helpful. Thank you!