代码：

<block wx:for="{{info.catalog}}" wx:key="{{index}}">
              <view class="wsui-flex wsui-main--between wsui-cross--center lesson-item lesson-bg">
                <view class="flex-grow-1 wsui-elip1 title">{{item}}</view>
                <view class="icon icon-gengduoyouhua"></view>
              </view>
              <block wx:for="{{info.catalog_child[index]}}" wx:key="{{itemm}}" wx:for-item="itemm" wx:for-index="indexx">
                <view class="wsui-flex wsui-main--between wsui-cross--center lesson-item lesson-sec">
                  <view class="flex-grow-1 wsui-elip1 title">{{index}}.{{itemm}}</view>
                </view>
              </block>
            </block>

要求做到如下样式