.butao{
    width: 100%;
    height: 100%;
    text-align: center;
    background: #000000;
    color: white;
    font-size: 60vh;
    border:none;
    outline:0px;
}
.invisivel{
    opacity: 0;
    display: none;
    scale: 0;
    transform: scale(0);
    pointer-events: 0;
    z-index: -1;
}