style(scss): 更新背景样式配置

- 为 .container.groups-index 添加背景色、圆角和模糊效果
- 统一多个选择器的视觉样式表现

scss/self.scss

@@ -50,7 +50,8 @@
 
 .regular.ember-view, .user-main, .reviewable,
 .admin-content, .contents.clearfix.body-page,
-.search-container, .show-badge, .users-directory, #main-outlet>.edit-category{
+.search-container, .show-badge, .users-directory, #main-outlet>.edit-category,
+.container.groups-index{
   background-color: #ffffffa8 !important;
   border-radius: var(--d-border-radius);
   backdrop-filter: blur(32px);