body,
html {
  font-family: Helvetica, Tahoma, Arial, "PingFang SC", "Hiragino Sans GB",
    "Heiti SC", STXihei, "Microsoft YaHei", SimHei, "WenQuanYi Micro Hei";
}

.flex-row {
  display: flex;
  flex-direction: row;
}

.flex-col {
  display: flex;
  flex-direction: column;
}

.flex-wrap {
  display: flex;
  flex-wrap: wrap;
}