It's not happening on the website for me right now, but it's an easy mistake that can happen for a variety of reasons, usually because the developer doesn't make it so that the menu that appears stays for a long enough time for you to move the mouse over to it before it disappears.
Of course it's the fault of the developer, but to get past this, if you're desperate:
1. Right click whatever you have to keep your mouse over, in this case it would be "MEN".
2. Press Inspect / Inspect Element
3. At the top right of the window that has just opened, there should be some tabs called Styles, Computed, Event Listeners and the such on Chrome, but similar on other browsers. Underneath that you should see :hov. Press that. On Firefox you should see an icon that looks like 3 little boxes next to a plus sign icon. You want to press the icon with the boxes on Firefox.
4. A new panel should be revealed underneath that. Now check the :hover box. This will force the MEN link to act as though you're hovering over it even when you're not.