Border of the shadow

Hi expert, the link  http://jsbin.com/momaquzufa/1/edit  is the layout with the help of  the expert Rion William. I tried to add the border to the top , left and right of  the shadow box, but after editing the code, the shadow box moves to the top, and it looks like the position of the shadow box cannot be controlled. Below is the editing code for the style, 
 .header { background: #FFF; -webkit-box-shadow:0px 5px 10px #1c1c1c;-moz-box-shadow:0px 5px 10px #1c1c1c;box-shadow:0px 5px 10px #1c1c1c;  border-width: 1px;     border-style: solid;   border-color: #DDD; width: 960px; margin: 0 auto;}
How to fix it?  How to add the border to the top, left and right of the shadow box without changing the position of the shadow box? Thank you!