miniprogram-demo/pages/component/picker-view/picker-view.wxss

.selected-date {
  text-align: center;
  margin: 15px;
}

.icon-container {
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
}

.picker-icon {
  width: 25px;
  height: 25px;
}