<view class="section"> <view class="section__title">flex-direction: row</view> <view class="flex-wrp" style="flex-direction:row;">  <view class="flex-item bc_green">1</view>  <view class="flex-item bc_red">2</view>  <view class="flex-item bc_blue">3</view> </view></view><view class="section"> <view class="section__title">flex-direction: column</view> <view class="flex-wrp" style="height: 300px;flex-direction:column;">  <view class="flex-item bc_green">1</view>  <view class="flex-item bc_red">2</view>  <view class="flex-item bc_blue">3</view> </view></view>