flat: 性能优化，animation 等\preload等

pages/careerfair/careerfair.vue

@@ -44,7 +44,7 @@
             <!-- 主体内容区域 -->
             <view class="container-main">
                 <scroll-view scroll-y class="main-scroll" @scrolltolower="handleScrollToLower">
-                    <view class="cards" v-if="fairList.length">
+                    <view class="cards">
                         <view
                             class="card press-button"
                             v-for="(item, index) in fairList"
@@ -94,7 +94,7 @@
                             <view class="card-footer">内容简介：{{ item.zphjj }}</view>
                         </view>
                     </view>
-                    <empty v-else></empty>
+                    <empty v-if="!fairList.length"></empty>
                 </scroll-view>
             </view>
             <!-- <Tabbar :currentpage="1"></Tabbar> -->