.photo-grid img {
    box-shadow:0px 3px 4px #dcdcdc;
    border-radius: 6px;
    /* 
    * Change this to try different borders
    */
    border:6px solid #FFF;
}
.photo-grid{
    /* 
     * Change this to set the spacing of the images in the grid
     */
    padding:10px;
}