div jump after it slide down

Question

I create a new page using HTMl and I whant when user clicks on one of my Links ,one div slide down at the bottom of it. the problem is when I using this code in my page it silde down in left side of my header and then it jump beneath my link.I save the code in jSfiddle :

http://jsfiddle.net/GMSvk/1/ in jsFiddle it jump up after slide down .please help me to solve this.

thanks

Answer 1

Add clear:both to #Specifications

http://jsfiddle.net/GMSvk/3/