@media (max-width: 767px) {
  $el {
    display:flex;
    flex-wrap: wrap;
  }
  $el .x-column {
    display: flex;
    flex-direction: column;
    flex: 0 0 33.3%;
    justify-content: center;
    align-items: center;
    margin: 0 0 20px;
  }
}