#main_bg_index  {
      position:absolute;
      z-index:1;
      width:980px;
      height:650px;
      left:50%;
      margin-left:-450px;
      margin-top:140px;
      background-image: url(../img/blue_index.jpg);
    }

    #main_bg_visi  {
      position:absolute;
      z-index:1;
      width:980px;
      height:650px;
      left:50%;
      margin-left:-450px;
      margin-top:140px;
      background-image: url(../img/blue_card.jpg);
    }

    #main_bg_letterheads  {
      position:absolute;
      z-index:1;
      width:980px;
      height:650px;
      left:50%;
      margin-left:-450px;
      margin-top:140px;
      background-image: url(../img/blue_letterheads.jpg);
    }

    #main_bg_letterheads  {
      position:absolute;
      z-index:1;
      width:980px;
      height:650px;
      left:50%;
      margin-left:-450px;
      margin-top:140px;
      background-image: url(../img/blue_blocks.jpg);
    }