fix: 稿件详情查看图片详情，对图片上滑查看时暂时的页码数字不清楚，与背景色相近时，几乎看不见

@@ -147,7 +147,7 @@ export struct MultiPictureListPage {
           // ImageDownloadComponent({ url: this.currentUrl })
           SaveNetWorkPictures({ url: this.currentUrl })
         }
-        .margin({
+        .padding({
           top: 14,
           left: 20,
           bottom: 14,
@@ -155,6 +155,11 @@ export struct MultiPictureListPage {
         })
         // .backgroundColor(Color.Blue)
         .id('e_swiper_titles')
+        .linearGradient({
+          direction: GradientDirection.Bottom, // 渐变方向
+          colors: [['rgba(18, 18, 18, 0)', 0],
+            ['rgba(18, 18, 18, 0.8)', 1.0]] // 数组末尾元素占比小于1时满足重复着色效果
+        })
         .alignRules({
           bottom: { anchor: "__container__", align: VerticalAlign.Bottom },
           middle: { anchor: "__container__", align: HorizontalAlign.Center }