.columns {
  display: flex;
  margin: 0 -20px;
}

.columns + .columns {
  margin-top: 60px;
}

.columns__item_third {
  width: 33.33%;
  padding: 0 20px;
}

.columns__item_half {
  width: 50%;
  padding: 0 20px;
}

@media only screen and (max-width : 480px) {
  .columns {
    flex-direction: column;
    margin: 0;
  }

  .columns + .columns {
    margin-top: 0;
  }

  .columns__item_third {
    width: 100%;
    padding: 20px 0;
  }

  .columns__item_half {
    width: 100%;
    padding: 20px 0;
  }
}