#outer {
        position: absolute;
        top: 50%;
        left: 0px;
        width: 100%;
        height: 1px;
        overflow: visible;
      }
       
      #inner {
position: absolute;
        width: 802px;
        height: 602px;
        margin-left: -400px;
        
        top: -300px;
        left: 50%;
      }