/* Botão branco */
.btn-branco {
  border: 2px solid #fff !important;   /* borda branca */
  color: #fff !important;              /* texto branco */
  background: transparent !important;  /* fundo transparente */
  transition: all 0.3s ease-in-out;
}

/* Hover */
.btn-branco:hover {
  background: #fff !important;   /* fundo branco */
  color: #000 !important;        /* texto preto */
}