Thank you, it is working perfectly.
I have found the underlying issue, it was not the custom CSS luckily. I had to enable this option, so that the overlay is area is displayed, but since you don’t want to actually show this hover-overlay, I also added this custom CSS to make it transparent:
/** Make overlay invisible **/
.asp_r_4 .asp_item_overlay {
opacity: 0 !important;
}It now acts as a transparent layer below the cursor, and should work as expected.