html,body,.full-height{
    height: 100%;
}.full-height{
    /* display: flex; */
    align-items: center;
    justify-content: center;
}.bienvenido{
    background: #fff;
}.alerta{
    position: absolute;
    width: 80%;
    left: 0;
    right: 0;
    top: 20px;
    margin: auto;
}