input.error {
   border: 1px solid red;
}

label.error {
   background: url('../images/unchecked.gif') no-repeat;
   padding-left: 16px;
   margin-left: .3em;
   font-weight:normal;
   color: red;
   margin-top:10px;
}

label.valid {
   background: url('../images/checked.gif') no-repeat;
   display: block;
   width: 16px;
   height: 16px;
}