Hi community,
I have put a top horizontal scroll to my IG, as shown on many examples from the internet but also from here.
So, I've set CSS Classes to this

And Inline CSS of the page by adding this:
.apex-igrid .a-GV-w-hdr {
overflow-x: auto !important; /* Enables top scrollbar */
}
However, my horizontal scroll is displayed like this, by interferring with the first row of the grid, and it's not scrollable, if I drag on it, it does not move"

if I go on the right side manually from cell to cell, I see it scrolled.

Just scrolling with the mouse does not work.
Any ideas why?