body {
    background-color: #000000;
}

.cor_fundo {
    background-color: #000000;
}

.max_width {
    max-width: 800px;
}

.centro {
    align-content: center;
    align-items: center;
    margin: auto;
}

.botao_voltar {
    position: fixed;
    left: 5px;
    top: 5px;
    z-index: 4;
}