I am using the Uber template. The popover that appears when you hover over the question mark next to the 'Keyword' as part of the JA K2 Filter Search module, is being hidden by the menu bar. How do I change the z-index in order to make it so that the popover appears in front of the menu bar behind it? What code can I put in the custom.css to resolve this issue? I have attached an image that shows what I want it to look like on the left (with the popover in front of the menu bar) and how it currently looks on the right (with the popover behind the menu bar). Please help.