优化样式表，更新字体引用，调整背景色，增强响应式设计；更新首页轮播图，添加新图片；重构JavaScript功能，增加客服小部件；修复HTML结构，确保页面加载顺畅。

joinus.html

@@ -242,12 +242,13 @@
         $("#footer").load("footer.html", function(){
         });
     </script>
-
-
-    <!-- Plugins for this template -->
-    <script src="assets/js/jquery-plugin-collection.js"></script>
-
-    <!-- Custom script for this template -->
+
+
+    <!-- Plugins for this template -->
+    <script src="assets/js/kefu.js"></script>
+    <script src="assets/js/jquery-plugin-collection.js"></script>
+
+    <!-- Custom script for this template -->
     <script src="assets/js/script.js"></script>
 </body>
 </html>