.flexbox .entry-content-wrapper {
  display: flex;
  flex-flow: row wrap;
  justify-content: space-between;
  align-items: center;  /*** if you have here stretch - the columns will be same height - but images not ***/
}

.flexbox .entry-content-wrapper:before,
.flexbox .entry-content-wrapper:after {
  display: none;
}

.flexbox .entry-content-wrapper .flex_column {
  margin: 0 0 30px;
  flex: 0 1 30%;
  background-color: #ddd;
}

@media only screen and (min-width: 768px) and (max-width: 989px) {
  .flexbox .entry-content-wrapper .flex_column {
    margin: 0 0 30px;
    flex: 0 1 48%;
    background-color: #ddd;
  }
}


@media only screen and (max-width: 767px) {
  .flexbox .entry-content-wrapper .flex_column {
    margin: 0 0 30px;
    flex: 1 1 100%;
    background-color: #ddd;
  }
}