.van-col {
  float: left;
  box-sizing: border-box;
}

.generate(24);
.generate(@n, @i: 1) when (@i =< @n) {
  .van-col--@{i} {
    width: @i * (100% / 24);
  }
  .van-col--offset-@{i} {
    margin-left: @i * (100% / 24);
  }
  .generate(@n, (@i + 1));
}