That's not bad, but why not add an inline friendly message? The best example is something like MyBB or XenForo. When you save a setting in the UCP or something similar, a green box comes up in MyBB to show it, and in XenForo the changes are made without ever leaving the page. Instead of the redirect, why not make it so when you click Submit and no text is found, it pops up a message saying 'Please input your search query!'.
I love everything else though. Maybe try and make the search box (box which contains the links) show up a little more on top of the background?