Add border around portfolio items

In order to add a border around portfolio items paste this code inside the dedicated area for  Custom CSS Code under the Theme Options Panel:

#portfolio img {
    border-left: 2px solid #fafafa;
    border-right: 2px solid #fafafa;
    border-top: 4px solid #fafafa;
}

Note that this code is just an experimental thing and it might not work properly. The theme doesn't have such feature, so margins are only possible with a hack (if it works properly).