Theme switch support (#3568)

### What problem does this PR solve?
- [x] New Feature (non-breaking change which adds functionality)

---------

Co-authored-by: Yingfeng <yingfeng.zhang@gmail.com>
Co-authored-by: Jin Hai <haijin.chn@gmail.com>

web/src/pages/chat/index.less

@@ -27,6 +27,12 @@
         border-radius: 8px;
       }
     }
+    .chatAppCardSelectedDark {
+      :global(.ant-card-body) {
+        background-color: rgba(255, 255, 255, 0.1);
+        border-radius: 8px;
+      }
+    }
   }
   .chatTitleWrapper {
     width: 220px;
@@ -62,6 +68,12 @@
       border-radius: 8px;
     }
   }
+  .chatTitleCardSelectedDark {
+    :global(.ant-card-body) {
+      background-color: rgba(255, 255, 255, 0.1);
+      border-radius: 8px;
+    }
+  }
 
   .divider {
     margin: 0;