.portada{
    /*background-color: #da2626;*/
    background: url(../img/portada.jpg) no-repeat fixed center;
   -webkit-background-size: cover;
   -moz-background-size: cover;
   -o-background-size: cover;
   background-size: cover;
   height: 100%;
   width: 100% ;
   text-align: center;
}