Add wmde-markdown-var wrapper

src/components/admin/MarkdownEditor.tsx

@@ -86,6 +86,7 @@ export function MarkdownEditor({
   return (
     <div className="space-y-2">
       <div data-color-mode={resolvedTheme}>
+        <div className="wmde-markdown-var" />
         <MDEditor
           value={value}
           onChange={(val) => onChange(val || '')}