style: 移除多余样式和属性，优化图片显示模式

- 移除多个组件中不必要的背景色样式
- 在图片预览组件中隐藏索引显示
- 将图片显示模式从 widthFix 改为 aspectFill
- 移除视频项中未使用的 duration 属性和相关格式化函数

@@ -445,7 +445,7 @@ const handleGoToPointsRule = () => {
 
 .points-rule-tip {
   position: absolute;
-  background-color: white;
+  // background-color: white;
   top: 0rpx;
   right: 0rpx;
   display: flex;

@@ -132,7 +132,7 @@ const handleGoToPointsRule = () => {
 
 .points-rule-tip {
   position: absolute;
-  background-color: white;
+  // background-color: white;
   top: 0rpx;
   right: 0rpx;
   display: flex;

@@ -21,7 +21,7 @@
           <image
             :src="item.type === 'video' ? item.thumbnail : item.url"
             class="w-full h-full object-cover"
-            mode="widthFix"
+            mode="aspectFill"
           />
 
           <!-- 视频播放标识 -->
@@ -54,6 +54,7 @@
       v-model:show="previewVisible"
       :images="previewImages"
       :init-no="previewIndex"
+      :show-index="false"
       @close="closePreview"
     />
 
@@ -120,7 +121,6 @@ const {
   handleVideoPause,
   handleFullscreenChange,
   handleVideoError,
-  formatDuration
 } = useMediaPreview();
 
 /**
@@ -162,7 +162,6 @@ const initMockData = () => {
       type: 'video',
       url: 'https://vjs.zencdn.net/v/oceans.mp4',
       thumbnail: 'https://img.yzcdn.cn/vant/apple-4.jpg',
-      duration: 30,
       createTime: '2024-01-11 18:30'
     },
     {
@@ -174,7 +173,6 @@ const initMockData = () => {
       type: 'video',
       url: 'https://vjs.zencdn.net/v/oceans.mp4',
       thumbnail: 'https://img.yzcdn.cn/vant/leaf.jpg',
-      duration: 60,
       createTime: '2024-01-09 15:20'
     },
     {
@@ -198,13 +196,6 @@ const initMockData = () => {
 const handleItemClick = (item, index) => {
   handleMediaClick(item, albumList.value);
 };
-
-/**
- * 返回上一页
- */
-const goBack = () => {
-  Taro.navigateBack();
-};
 </script>
 
 <style scoped>

@@ -143,6 +143,7 @@
       v-model:show="previewVisible"
       :images="previewImages"
       :init-no="previewIndex"
+      :show-index="false"
       @close="closePreview"
     />
 
@@ -246,7 +247,6 @@ const albumData = ref([
     type: 'video',
     url: 'https://vjs.zencdn.net/v/oceans.mp4',
     thumbnail: 'https://cdn.ipadbiz.cn/hager/0513-1_FsxMk28AGz6N_D1zZFFOl_EaRdss.png',
-    duration: 125,
     createTime: '2024-01-14 16:20'
   }
 ]);