#zona_inferior {
    border-top: 1px solid;
    position: relative;
    clear: both;
    z-index: 10;
    width: auto;
  }
  .caja_inferior {
    margin: 5px;
    float: left;
    clear: right;
    width: 18em;
    height: 100%;
    vertical-align: top;
  }
   .con_barra {
    padding: 5px;
    border-right: 3px solid #000080;
  }
</c:if>