.cont#autenticar{
    display: flex; justify-content:center; align-items:center; 
    margin:1em auto;
}
.cont#autenticar>div{
    min-width:320px;
    padding:2em 1em 1em;
    border:1px solid lightgrey;border-radius:.6em;box-shadow: 4px 4px 8px black;
}
.cont#autenticar form{
    display:block; margin:auto;
}
.cont#autenticar form>div{
    margin-bottom:.3em;
}
.text-justify{
    text-align:justify;
}