.my_account:before {
position: absolute;
    width: 0%;
    height: 0px;
    bottom: 0px;
    left: 0;
    content: "";
    background: var(--cor_cabecalho);
}

.dropHelp:before {
    position: absolute;
    width: 0%;
    height: 0px;
    bottom: -10px;
    left: 0;
    content: "";
    background: var(--cor_cabecalho);