.div_fs_msg {
    position: absolute;
    border: 1px outset black;
    background: gray;
    width: 100%;
    height: 100%;
    left: 0;
    top: 0;
    z-index: 100;
    opacity: 1.0;
    text-align: center;
    visibility: visible;
    overflow: hidden;
    font: 40px Arial, Helvetica, sans-serif;	
}

/*  
    animação: transicao do oculto para visivel
*/
@keyframes fade_in {

    0% {/* comeca 100% transparente*/
      opacity:0%;
    }
  
    100% {/* termina 100% opaco*/
      opacity: 100%;
    }
}

@keyframes fade_out {

    0% {/* comeca 100% transparente*/
      opacity:100%;
    }
  
    100% {/* termina 100% opaco*/
      opacity: 0%;
    }
}