Add a shadow to the body

body-shadow.css

body:before { 
    content: "";
    position: fixed; 
    top: -10px; 
    left: 0; 
    width: 100%; 
    height: 10px; 
    box-shadow: 0px 0px 10px rgba(0,0,0,.5); 
    z-index:100; 
}