add the class attribute for beian information

Author: idiks

layouts/partials/layout/footer-cn.html

@@ -65,6 +65,6 @@ <h4 class="list-title"><strong>联系我们</strong></h4>
     <div class="container copyright-container">
         <p class="copyright">&copy; 2025 小长科技（上海）有限公司</p>
         <a href="{{ or $data_i18_link .Params.data_i18_page_link }}" class="copyright-btn-lang copyright-btn-en" id="lang">English</a>
-        <a href="https://beian.miit.gov.cn/" target="_blank">沪ICP备14049619号-2</a>
+        <a href="https://beian.miit.gov.cn/" target="_blank" class="prepared-num">沪ICP备14049619号-2</a>
     </div>
 </footer>