CSS : z-index/stacking issue

I've been working on a new version of my web开发者_高级运维site, and to make it cleaner I installed a jQuery Dropdown menu, so the navigation looks cleaner.

The thing is, the links appear underneath the following content div, and I'm not sure how I can fix this.. I've looked into the z-index property, and I tried setting the position and z-index of both divs, but to no avail, they stay improperly stacked.

Here's the link of the page, so you can see what I mean : http://minecrafteurope.com/?theme=compositio

Any idea on how I can fix this ?

Thanks ! Mark

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Remove overflow: hidden; from .menu