.textbox
{
   border:solid 1px #919191;
   height:18px;   
   font-family:Arial;
   padding-top:3px;
   color: #919191;
   background: white;
   background-repeat:repeat;
   font-size:12px;
   
}

.textbox_invalid
{
   border: ridge 1px red;
   height:18px;    
   padding-top:3px;
   background-color:#ef8d8d;
}