Div Overlapping incorrectly

I am trying to implement a menu into an area.

http://www.gardensandhomesdirect.co.uk/newhomepage

You will see the end of the menu div slightly off the page to the right, however this needs to be inside the HOMEMENU section (the long black bar with no content)

It seems to be overflowing into other areas, despite using a clear:both div.

Can anyone shed any light on this? Is it a z-index issue or s开发者_JAVA技巧omething more simple?

---

You have a width: 930px; somewhere.

Remove it.

#topmenu {
    list-style: none;
    **width: 930px;**
    height: 20px;
    background: #014464;
    border: 1px solid #002232;
}

When I inspect the element (menu-bar) is see there are some space (like) characters outputted.