.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: 1px solid #ff0000;
  border-radius: 50%;
}
