Indicator Opacity on main-menu

Hi,

I have a problem with the indicator on my sub-menus. I you go to the Collaborations/universities and research centers/ In Europe the sub menu under In Europe will probably open on the left, based on you browser’s width. If so, you will see that the indicator on the previous sub-menu is visible on this menu. Does anybody know how it is possible to make it invisible when this sub-menu is on top?

I have already checked the opacity of the sub-menu and it’s on maximum value.

The page I need help with: [log in to see the link]