If you're refering to having your images and boxes with a drtop shadow, then you need the Box Shadow CSS feature to work for you. Here's what you need to place in your CSS:

.shadow {
  box-shadow: 3px 3px 3px #f2f2f2;
  -moz-box-shadow: 3px 3px 3px #f2f2f2;
  -webkit-box-shadow: 3px 3px 3px #f2f2f2;
}