优化样式，调整背景颜色透明度以提升视觉效果；更新 MediaCardListView 组件，增加上边距以改善布局；在 PluginCardListView 组件中添加新版本过滤条件，优化过滤逻辑和用户交互体验。

src/@core/scss/base/placeholders/_misc.scss

@@ -59,8 +59,8 @@
           rgba(11, 11, 11, 0.8) 0%,
           rgba(11, 11, 11, 0.7) 20%,
           rgba(11, 11, 11, 0.6) 40%,
-          rgba(11, 11, 11, 0.3) 60%,
-          rgba(11, 11, 11, 0.1) 80%,
+          rgba(11, 11, 11, 0.4) 60%,
+          rgba(11, 11, 11, 0.2) 80%,
           rgba(11, 11, 11, 0.0) 100%
         );
       }