@media (max-width: 600px) {
    .botao-whatsapp {
        right: 15px;
        bottom: 75px;
        width: 150px;
        height: 54px;
    }
}

.botao-whatsapp {
    position: fixed;
    right: 20px;
    bottom: 80px;
    width: 150px;
    height: 54px;
    z-index: 1000;
}

.botao-whatsapp img {
    display: block;
    width: 100%;
    height: auto;
}