fix: pre tag background color adjustment, remove the background color of the quoted content

Author: shuashuai

ui/src/components/Editor/Viewer.tsx

@@ -78,7 +78,7 @@ const Index = ({ value }, ref) => {
     <ImgViewer>
       <div
         ref={previewRef}
-        className="preview-wrap position-relative p-3 bg-light rounded text-break text-wrap mt-2 fmt"
+        className="preview-wrap position-relative p-3 rounded text-break text-wrap mt-2 fmt"
         dangerouslySetInnerHTML={{ __html: html }}
       />
     </ImgViewer>

ui/src/index.scss

@@ -247,17 +247,16 @@ img[src=''] {
     }
   }
   pre {
-    background-color: var(--an-e9ecef);
+    background-color: var(--bs-gray-100);
     border-radius: 0.25rem;
     padding: 1rem;
     max-height: 38rem;
-    white-space: normal;
+    white-space: pre-wrap;
   }
   blockquote {
     border-left: 0.25rem solid #ced4da;
     padding: 1rem;
     color: #6c757d;
-    background-color: var(--an-e9ecef);
     p {
       color: var(--bs-body-color);
     }