.loader
  {
     position: fixed;
     z-index: 1800;
     background-image: url('VisitPagecss/Images/loading.gif');
      background-repeat: no-repeat;
     background-position: center center;
     width: 100%;
      height: 100%;
     opacity: 0.6;
     background-color: #CCCCCC;
      display: none;
  }