fix: 404 page and 50X page ui changed

i18n/en_US.yaml

@@ -1016,9 +1016,11 @@ ui:
     answers: answers
     accepted: Accepted
   page_404:
+    http_error: HTTP Error 404
     desc: "Unfortunately, this page doesn't exist."
     back_home: Back to homepage
   page_50X:
+    http_error: HTTP Error 500
     desc: The server encountered an error and could not complete your request.
     back_home: Back to homepage
   page_maintenance:

ui/src/pages/404/index.jsx

@@ -25,7 +25,8 @@ const Index = () => {
         style={{ fontSize: '120px', lineHeight: 1.2 }}>
         (=‘x‘=)
       </div>
-      <div className="text-center mb-4">{t('desc')}</div>
+      <h4 className="text-center mb-2">{t('http_error')}</h4>
+      <div className="text-center mb-3">{t('desc')}</div>
       <div className="text-center">
         <Button as={Link} to="/" variant="link">
           {t('back_home')}

ui/src/pages/50X/index.jsx

@@ -21,6 +21,8 @@ const Index = () => {
         style={{ fontSize: '120px', lineHeight: 1.2 }}>
         (=T^T=)
       </div>
+
+      <h4 className="text-center mb-2">{t('http_error')}</h4>
       <div className="text-center mb-3">{t('desc')}</div>
       <div className="text-center">
         <Button as={Link} to="/" variant="link">