.option_item {
    display: flex;
    flex-wrap: wrap;
  }
  .option_item li {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    flex: 0 0 50%;
    margin-bottom: 20%;
  }
  .option_item li img {
    max-width: 55%;
  }
  .option_item li img.selected {
    border: 2px solid #ff0000;
    border-radius: 50%;
  }
  