Feat: dataset dark mode (#17993)

web/app/components/datasets/create/file-preview/index.tsx

@@ -2,6 +2,7 @@
 import React, { useEffect, useState } from 'react'
 import { useTranslation } from 'react-i18next'
 import { XMarkIcon } from '@heroicons/react/20/solid'
+import Loading from '@/app/components/base/loading'
 import s from './index.module.css'
 import cn from '@/utils/classnames'
 import type { CustomFile as File } from '@/models/datasets'
@@ -57,7 +58,7 @@ const FilePreview = ({
         </div>
       </div>
       <div className={cn(s.previewContent)}>
-        {loading && <div className={cn(s.loading)} />}
+        {loading && <Loading type='area' />}
         {!loading && (
           <div className={cn(s.fileContent, 'body-md-regular')}>{previewContent}</div>
         )}