diff --git a/README.md b/README.md
index 8e645ed..bc5a7d1 100644
--- a/README.md
+++ b/README.md
@@ -7,14 +7,14 @@ This document presents an example of dynamic permission menu loading based on jC
 
 **Technology Stack**
 
-- **Backend:** Spring Boot 3.x + jCasbin + Spring Data JPA
+- **Backend:** Spring Boot 2.x + jCasbin + Spring Data JPA
 - **Frontend:** Bootstrap + Thymeleaf
 
 **Startup Instructions**
 
-1. Build the menu structure you need in the `casbin/policy.csv` file. Specifically, `g2` represents the relationship between menus. For example: `g2, submenu name, parent menu name`.
-2. Once the configuration is complete, run the `main` method in `Application.java` located under `org/casbin/`. Access `http://localhost:8080/casbin/menu` for testing. 
-3. The access control model file for jCasbin is located at `casbin/model.conf`, and the policy file is at `casbin/policy.csv`. Modify them as needed based on your requirements.
+1. Build the menu structure you need in the [`casbin/policy.csv`](https://github.com/jcasbin/jcasbin-menu-permission/blob/master/src/main/resources/casbin/policy.csv) file. Specifically, `g2` represents the relationship between menus. For example: `g2, submenu name, parent menu name`.
+2. Once the configuration is complete, run the `main` method in [`Application.java`](https://github.com/jcasbin/jcasbin-menu-permission/blob/master/src/main/java/org/casbin/Application.java) located under `org/casbin/`. Access `http://localhost:8080/casbin/menu` for testing. 
+3. The access control model file for jCasbin is located at [`casbin/model.conf`](https://github.com/jcasbin/jcasbin-menu-permission/blob/master/src/main/resources/casbin/model.conf), and the policy file is at [`casbin/policy.csv`](https://github.com/jcasbin/jcasbin-menu-permission/blob/master/src/main/resources/casbin/policy.csv). Modify them as needed based on your requirements.
 
 ## Simple Examples
 
@@ -24,14 +24,14 @@ This document presents an example of dynamic permission menu loading based on jC
   <source src="examples/example.mp4" type="video/mp4">
 </video>
 
-**System user**
+**Root user**
 
-<img src="examples/system_example.png" alt="system_example" style="zoom:80%;" />
+<img src="examples/root_example.png" alt="system_example" style="zoom:60%;" />
 
 **Admin user**
 
-<img src="examples/admin_example.png" alt="admin_example" style="zoom:80%;" />
+<img src="examples/admin_example.png" alt="admin_example" style="zoom:60%;" />
 
 **Normal user**
 
-<img src="examples/user_example.png" alt="user_example" style="zoom:80%;" />
\ No newline at end of file
+<img src="examples/user_example.png" alt="user_example" style="zoom:60%;" />
\ No newline at end of file
diff --git a/examples/admin_example.png b/examples/admin_example.png
index 619e48c..3d78cbd 100644
Binary files a/examples/admin_example.png and b/examples/admin_example.png differ
diff --git a/examples/example.mp4 b/examples/example.mp4
index 1c4a6a8..04a839c 100644
Binary files a/examples/example.mp4 and b/examples/example.mp4 differ
diff --git a/examples/root_example.png b/examples/root_example.png
new file mode 100644
index 0000000..73edee8
Binary files /dev/null and b/examples/root_example.png differ
diff --git a/examples/system_example.png b/examples/system_example.png
deleted file mode 100644
index 24e98a4..0000000
Binary files a/examples/system_example.png and /dev/null differ
diff --git a/examples/user_example.png b/examples/user_example.png
index 505ac76..5b0bd30 100644
Binary files a/examples/user_example.png and b/examples/user_example.png differ
diff --git a/src/main/java/org/casbin/config/WebMvcConfig.java b/src/main/java/org/casbin/config/WebMvcConfig.java
index c14768b..0ee7bd3 100644
--- a/src/main/java/org/casbin/config/WebMvcConfig.java
+++ b/src/main/java/org/casbin/config/WebMvcConfig.java
@@ -51,15 +51,12 @@ public boolean preHandle(HttpServletRequest request, HttpServletResponse respons
                 // Extract the menu name, assuming it is the last part of the URI.
                 String menuName = requestURI.substring(requestURI.lastIndexOf('/') + 1);
 
-                if(menuService.checkUserAccess(username, "ALL_ROOT")) return true;
-
                 if (username == null) {
                     // The user is not logged in
                     response.sendRedirect(request.getContextPath() + "/denied");
                     return false;
                 }
-
-                if (!menuService.checkUserAccess(username, menuName)) {
+                if (!menuService.checkMenuAccess(username, menuName)) {
                     // Users do not have access to the menu.
                     response.sendRedirect(request.getContextPath() + "/denied");
                     return false;
diff --git a/src/main/java/org/casbin/controller/TestMenuController.java b/src/main/java/org/casbin/controller/TestMenuController.java
index 3230633..1b82a3a 100644
--- a/src/main/java/org/casbin/controller/TestMenuController.java
+++ b/src/main/java/org/casbin/controller/TestMenuController.java
@@ -19,6 +19,10 @@
 
 @Controller
 public class TestMenuController {
+    @GetMapping(value = "menu/UserMenu")
+    public String UserMenu(){
+        return "UserMenu/UserMenu";
+    }
     @GetMapping(value = "menu/UserSubMenu_allow")
     public String UserSubMenu_allow(){
         return "UserMenu/UserSubMenu_allow";
@@ -29,6 +33,16 @@ public String UserSubMenu_deny(){
         return "UserMenu/UserSubMenu_deny";
     }
 
+    @GetMapping(value = "menu/UserSubSubMenu")
+    public String UserSubMenu_sub(){
+        return "UserMenu/UserSubSubMenu";
+    }
+
+    @GetMapping(value = "menu/AdminMenu")
+    public String AdminMenu(){
+        return "AdminMenu/AdminMenu";
+    }
+
     @GetMapping(value = "menu/AdminSubMenu_allow")
     public String AdminSubMenu_allow(){
         return "AdminMenu/AdminSubMenu_allow";
@@ -39,9 +53,9 @@ public String AdminSubMenu_deny(){
         return "AdminMenu/AdminSubMenu_deny";
     }
 
-    @GetMapping(value = "menu/SystemMenu")
+    @GetMapping(value = "menu/OtherMenu")
     public String SystemMenu(){
-        return "SystemMenu/SystemMenu";
+        return "OtherMenu/OtherMenu";
     }
 
 }
diff --git a/src/main/java/org/casbin/entity/MenuEntity.java b/src/main/java/org/casbin/entity/MenuEntity.java
index f468630..8c4e7f0 100644
--- a/src/main/java/org/casbin/entity/MenuEntity.java
+++ b/src/main/java/org/casbin/entity/MenuEntity.java
@@ -20,6 +20,7 @@
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Objects;
 
 /**
  * Menu Entity
@@ -46,4 +47,19 @@ public void addSubMenu(MenuEntity subMenu) {
         this.subMenus.add(subMenu);
         subMenu.setParents(this);
     }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+        MenuEntity that = (MenuEntity) o;
+        return Objects.equals(name, that.name) &&
+                Objects.equals(url, that.url);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(name, url, subMenus);
+    }
+
 }
\ No newline at end of file
diff --git a/src/main/java/org/casbin/service/AuthenticationService.java b/src/main/java/org/casbin/service/AuthenticationService.java
index c69bb0b..aa16180 100644
--- a/src/main/java/org/casbin/service/AuthenticationService.java
+++ b/src/main/java/org/casbin/service/AuthenticationService.java
@@ -20,7 +20,7 @@
 public class AuthenticationService {
     public boolean authenticate(String username, String password) {
         // Three valid username and password combinations are set here.
-        return ("system".equals(username) && "system".equals(password)) ||
+        return ("root".equals(username) && "root".equals(password)) ||
                 ("admin".equals(username) && "admin".equals(password)) ||
                 ("user".equals(username) && "user".equals(password));
     }
diff --git a/src/main/java/org/casbin/service/MenuService.java b/src/main/java/org/casbin/service/MenuService.java
index 149a1ab..b9dbdf0 100644
--- a/src/main/java/org/casbin/service/MenuService.java
+++ b/src/main/java/org/casbin/service/MenuService.java
@@ -28,7 +28,6 @@
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
-import java.util.stream.Collectors;
 
 /**
  * The MenuService class handles menu-related business logic, including permission control and menu filtering, using the jCasbin permission library.
@@ -53,12 +52,7 @@ public List<MenuEntity> findAccessibleMenus(String username) {
             this.menuMap = new HashMap<>();
         }
         this.accessMap = new HashMap<>();
-        // Check if there is ALL_ROOT permission
-        if (checkUserAccess(username, "ALL_ROOT")) {
-            return menuMap.values().stream()
-                    .filter(this::isTopLevelMenu)
-                    .collect(Collectors.toList());
-        }
+
         List<MenuEntity> accessibleMenus = new ArrayList<>();
         for (MenuEntity menu : menuMap.values()) {
             checkAndSetMenuAccess(menu, username);
@@ -102,9 +96,31 @@ private boolean isTopLevelMenu(MenuEntity menu) {
         return menu.getParents() == null;
     }
 
-    public boolean checkUserAccess(String username, String menuName) {
+    private boolean checkUserAccess(String username, String menuName) {
         // Integrate Casbin to check user access to specific menus
         return enforcer.enforce(username, menuName, "read");
     }
-}
 
+    public boolean checkMenuAccess(String username, String menuName) {
+        List<MenuEntity> accessibleMenus = findAccessibleMenus(username);
+        for (MenuEntity menu : accessibleMenus) {
+            if (menuMatches(menu, menuName)) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    private boolean menuMatches(MenuEntity menu, String menuName) {
+        if (menu.getName().equals(menuName)) {
+            return true;
+        }
+        for (MenuEntity subMenu : menu.getSubMenus()) {
+            if (menuMatches(subMenu, menuName)) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+}
\ No newline at end of file
diff --git a/src/main/java/org/casbin/util/MenuUtil.java b/src/main/java/org/casbin/util/MenuUtil.java
index cc65c1d..6ddf3ca 100644
--- a/src/main/java/org/casbin/util/MenuUtil.java
+++ b/src/main/java/org/casbin/util/MenuUtil.java
@@ -36,17 +36,22 @@ public static Map<String, MenuEntity> parseCsvFile(String filePath) throws IOExc
                     String childName = values[1].trim();
                     String parentName = values[2].trim();
 
-                    menuMap.putIfAbsent(childName, new MenuEntity(childName));
-                    if (!parentName.isEmpty()) {
+                    // Check whether the name of the submenu is "(NULL)"
+                    if (!"(NULL)".equals(childName)) {
+                        menuMap.putIfAbsent(childName, new MenuEntity(childName));
+                        if (!parentName.isEmpty()) {
+                            menuMap.putIfAbsent(parentName, new MenuEntity(parentName));
+                            MenuEntity childMenu = menuMap.get(childName);
+                            MenuEntity parentMenu = menuMap.get(parentName);
+                            parentMenu.addSubMenu(childMenu);
+                        }
+                    } else if (!parentName.isEmpty()) {
+                        // Add only the parent menu, no submenu.
                         menuMap.putIfAbsent(parentName, new MenuEntity(parentName));
-                        MenuEntity childMenu = menuMap.get(childName);
-                        MenuEntity parentMenu = menuMap.get(parentName);
-                        parentMenu.addSubMenu(childMenu);
                     }
                 }
             }
         }
         return menuMap;
     }
-}
-
+}
\ No newline at end of file
diff --git a/src/main/resources/casbin/policy.csv b/src/main/resources/casbin/policy.csv
index d65a395..0718e0a 100644
--- a/src/main/resources/casbin/policy.csv
+++ b/src/main/resources/casbin/policy.csv
@@ -1,18 +1,19 @@
-p, ROLE_SYSTEM, ALL_ROOT, read, allow
+p, ROLE_ROOT, OtherMenu, read, allow
+p, ROLE_ROOT, AdminMenu, read, allow
+p, ROLE_ROOT, UserMenu, read, deny
 p, ROLE_ADMIN, UserMenu, read, allow
 p, ROLE_ADMIN, AdminMenu, read, allow
 p, ROLE_ADMIN, AdminSubMenu_deny, read, deny
 p, ROLE_USER, UserSubMenu_allow, read, allow
 
 g, user, ROLE_USER
-g, admin, ROLE_USER
 g, admin, ROLE_ADMIN
-g, system, ROLE_SYSTEM
+g, root, ROLE_ROOT
+g, ROLE_ADMIN, ROLE_USER
 
 g2, UserSubMenu_allow, UserMenu
 g2, UserSubMenu_deny, UserMenu
+g2, UserSubSubMenu, UserSubMenu_allow
 g2, AdminSubMenu_allow, AdminMenu
 g2, AdminSubMenu_deny, AdminMenu
-g2, , SystemMenu
-
-
+g2, (NULL), OtherMenu
\ No newline at end of file
diff --git a/src/main/resources/templates/AdminMenu/AdminMenu.html b/src/main/resources/templates/AdminMenu/AdminMenu.html
new file mode 100644
index 0000000..c986868
--- /dev/null
+++ b/src/main/resources/templates/AdminMenu/AdminMenu.html
@@ -0,0 +1,13 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <title>AdminMenu</title>
+</head>
+<body>
+<div>
+    AdminMenu
+</div>
+
+</body>
+</html>
\ No newline at end of file
diff --git a/src/main/resources/templates/SystemMenu/SystemMenu.html b/src/main/resources/templates/OtherMenu/OtherMenu.html
similarity index 90%
rename from src/main/resources/templates/SystemMenu/SystemMenu.html
rename to src/main/resources/templates/OtherMenu/OtherMenu.html
index 1d3f769..cddee05 100644
--- a/src/main/resources/templates/SystemMenu/SystemMenu.html
+++ b/src/main/resources/templates/OtherMenu/OtherMenu.html
@@ -6,7 +6,7 @@
 </head>
 <body>
 <div>
-    SystemMenu
+    OtherMenu
 </div>
 
 </body>
diff --git a/src/main/resources/templates/UserMenu/UserMenu.html b/src/main/resources/templates/UserMenu/UserMenu.html
new file mode 100644
index 0000000..f06186b
--- /dev/null
+++ b/src/main/resources/templates/UserMenu/UserMenu.html
@@ -0,0 +1,13 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <title>UserMenu</title>
+</head>
+<body>
+<div>
+    UserMenu
+</div>
+
+</body>
+</html>
\ No newline at end of file
diff --git a/src/main/resources/templates/UserMenu/UserSubSubMenu.html b/src/main/resources/templates/UserMenu/UserSubSubMenu.html
new file mode 100644
index 0000000..1b580eb
--- /dev/null
+++ b/src/main/resources/templates/UserMenu/UserSubSubMenu.html
@@ -0,0 +1,13 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <title>UserSubSubMenu</title>
+</head>
+<body>
+<div>
+    UserSubSubMenu
+</div>
+
+</body>
+</html>
\ No newline at end of file
diff --git a/src/main/resources/templates/main/menu.html b/src/main/resources/templates/main/menu.html
index b00be01..960f8b6 100644
--- a/src/main/resources/templates/main/menu.html
+++ b/src/main/resources/templates/main/menu.html
@@ -21,35 +21,60 @@
         .card-body p {
             padding-left: 20px;
         }
+        .submenu-background {
+            background-color: #f8f9fa;
+            padding: 10px;
+            border-radius: 5px;
+            margin-top: 5px;
+        }
+
     </style>
 </head>
 <body>
 
-<div id="main" class="container-fluid">
-    <div id="main_nav" class="d-inline-block">
-        <!-- Collapse menu -->
-        <div id="accordion">
-            <!-- collapsible items -->
-            <div th:each="menu, menuStat: ${menus}" th:if="${menu.subMenus.size() != 0 && menu.subMenus != null}" class="card">
+<!-- Recursive menu fragment -->
+<div th:fragment="menuFragment(menuList, isTopLevel)">
+    <div th:each="menu, menuStat: ${menuList}">
+        <!-- Items with submenus -->
+        <div th:if="${menu.subMenus.size() != 0 && menu.subMenus != null}">
+            <div th:if="${isTopLevel}" class="card">
                 <div class="card-header">
                     <h4 class="mb-0">
                         <button class="btn btn-link" type="button" data-toggle="collapse" th:data-target="| #collapse${menuStat.index} |">
-                            <span th:text="${menu.name}">Menu 1</span>
+                            <span th:src="${menu.url}" th:text="${menu.name}">Menu Name</span>
                         </button>
                     </h4>
                 </div>
 
                 <div th:id="|collapse${menuStat.index}|" class="collapse" data-parent="#accordion">
                     <div class="card-body">
-                        <p th:each="subMenu:${menu.subMenus}" th:src="${subMenu.url}" th:text="${subMenu.name}">Submenu 1</p>
+                        <div th:replace="this :: menuFragment(${menu.subMenus}, false)"></div>
                     </div>
                 </div>
             </div>
-            <!-- Uncollapsed items -->
-            <div th:each="menu:${menus}" th:if="${menu.subMenus.size() == 0}" class="non-collapse-item">
-                <p th:text="${menu.name}" th:src="${menu.url}">Menu 2</p>
+            <div th:unless="${isTopLevel}" class="submenu-background">
+                <button class="btn btn-link" type="button" data-toggle="collapse" th:data-target="| #collapseSub${menuStat.index} |">
+                    <span th:src="${menu.url}" th:text="${menu.name}">Submenu Name</span>
+                </button>
+                <div th:id="|collapseSub${menuStat.index}|" class="collapse">
+                    <div th:replace="this :: menuFragment(${menu.subMenus}, false)"></div>
+                </div>
             </div>
         </div>
+
+        <!-- No submenu items -->
+        <div th:if="${menu.subMenus.size() == 0}">
+            <a th:src="${menu.url}" th:text="${menu.name}">Menu Item</a>
+        </div>
+    </div>
+</div>
+
+<div id="main" class="container-fluid">
+    <div id="main_nav" class="d-inline-block">
+        <div id="accordion">
+            <!-- Call the recursive fragment -->
+            <div th:replace="this :: menuFragment(${menus}, true)"></div>
+        </div>
         <div class="logout-button-container">
             <button id="logoutButton" class="btn btn-danger">log out</button>
         </div>