diff --git a/frontend/Web/communication.js b/frontend/Web/communication.js
index 6c12c84..15369a9 100644
--- a/frontend/Web/communication.js
+++ b/frontend/Web/communication.js
@@ -69,6 +69,8 @@ async function Request(req)
   localStorage.setItem("operation_count", operation_count);
   return response;
 }
+
+var SessionReadyEvent = new Event('SessionReady');
 (async () => {
   if(session_token==null||outhentication_key==null||operation_count==null){
     let tmp_channel=generateRandomString(10);
@@ -79,6 +81,7 @@ async function Request(req)
     localStorage.setItem("session_token", session_token);
     localStorage.setItem("outhentication_key", outhentication_key);
     localStorage.setItem("operation_count", operation_count);
+    document.dispatchEvent(SessionReadyEvent);
   }
 })();
 
diff --git a/frontend/Web/index.html b/frontend/Web/index.html
index 005205e..e9fdeea 100644
--- a/frontend/Web/index.html
+++ b/frontend/Web/index.html
@@ -135,7 +135,7 @@
             <a href="#" onclick="(async () => { await Request('logout'); await UpdateUserInfo(); })();">Logout</a>
             <a href="#" onclick="localStorage.removeItem('session_token'); localStorage.removeItem('outhentication_key'); localStorage.removeItem('operation_count'); window.close();">Close Session</a>
             <a href="/register">Register</a>
-            <a href="#">Change Password</a>
+            <a href="/passwd">Change Password</a>
             <a href="#">Admin Panel</a>
           </div>
         </div>
@@ -194,7 +194,9 @@
         ChangeUsername(nm+" [Admin]");
       }
     }
-    UpdateUserInfo();
+    document.addEventListener('SessionReady', async () => {
+      await UpdateUserInfo();
+    });
   </script>
 </body>
 </html>
\ No newline at end of file
diff --git a/frontend/Web/index.js b/frontend/Web/index.js
index 6d9f8ee..c45caf3 100644
--- a/frontend/Web/index.js
+++ b/frontend/Web/index.js
@@ -162,6 +162,10 @@ app.get('/register', (req, res) => {
   res.sendFile(join(__dirname, 'register.html'));
 });
 
+app.get('/passwd', (req, res) => {
+  res.sendFile(join(__dirname, 'passwd.html'));
+});
+
 server.listen(3000, () => {
   console.log('server running at http://localhost:3000');
 });
\ No newline at end of file
diff --git a/frontend/Web/login.html b/frontend/Web/login.html
index 1e64395..fc4c74c 100644
--- a/frontend/Web/login.html
+++ b/frontend/Web/login.html
@@ -146,6 +146,17 @@
             border: none;
             cursor: pointer;
         }
+        .info-box {
+      width: 300px;
+      padding: 20px;
+      border: 1px solid #ccc;
+      background-color: #fff;
+      box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
+      position: absolute;
+      top: 50%;
+      left: 50%;
+      transform: translate(-50%, -50%);
+    }
   </style>
 </head>
 <body>
@@ -162,7 +173,7 @@
             <a href="#" onclick="(async () => { await Request('logout'); await UpdateUserInfo(); })();">Logout</a>
             <a href="#" onclick="localStorage.removeItem('session_token'); localStorage.removeItem('outhentication_key'); localStorage.removeItem('operation_count'); window.close();">Close Session</a>
             <a href="/register">Register</a>
-            <a href="#">Change Password</a>
+            <a href="/passwd">Change Password</a>
             <a href="#">Admin Panel</a>
           </div>
         </div>
@@ -225,7 +236,9 @@
         ChangeUsername(nm+" [Admin]");
       }
     }
-    UpdateUserInfo();
+    document.addEventListener('SessionReady', async () => {
+      await UpdateUserInfo();
+    });
     async function TryLogin()
     {
       console.log("TryLogin called");
@@ -238,8 +251,9 @@
       }
       else
       {
-        UpdateUserInfo();
-        window.location.href="/";
+        await UpdateUserInfo();
+        document.querySelector('.content').innerHTML = '<div class="info-box"><h2>Login Success</h2><p>Redirecting to home page in 3 seconds...</p></div>';
+        setTimeout(function(){window.location.href="/";},3000);
       }
     }
   </script>
diff --git a/frontend/Web/passwd.html b/frontend/Web/passwd.html
new file mode 100644
index 0000000..97a409a
--- /dev/null
+++ b/frontend/Web/passwd.html
@@ -0,0 +1,273 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+  <meta name="viewport" content="width=device-width, initial-scale=1.0">
+  <title>change password - ZYM's Book Store</title>
+  <style>
+    body {
+      margin: 0;
+      font-family: Arial, sans-serif;
+    }
+
+    header {
+      background-color: #333;
+      color: #fff;
+      padding: 10px 0;
+      text-align: center;
+    }
+
+    .user-bar {
+      float: right;
+      padding: 10px;
+      background-color: #007bff;
+    }
+
+    .user-bar span {
+      margin-right: 20px; /* Add spacing between "Welcome, Guest" and "Actions" */
+    }
+
+    .user-bar a {
+      color: #fff;
+      margin-right: 10px;
+      text-decoration: none;
+    }
+
+    .user-bar a:hover {
+      text-decoration: underline;
+    }
+
+    .action-button-container {
+      display: inline-block;
+    }
+
+    .action-button {
+      padding: 10px 15px;
+      background-color: #007bff;
+      color: #fff;
+      border: 2px solid #0056b3; /* Dark blue border */
+      border-radius: 5px; /* Rounded corners */
+      cursor: pointer;
+      display: inline-block;
+    }
+
+    .action-button:hover,
+    .dropdown-content:hover {
+      background-color: #87CEFA; /* Light blue background on hover */
+    }
+
+    .dropdown {
+      position: relative;
+      display: inline-block;
+    }
+
+    .dropdown-content {
+      display: none;
+      position: absolute;
+      background-color: #87CEFA; /* Light blue background */
+      box-shadow: 0 8px 16px rgba(0,0,0,0.1);
+      z-index: 1;
+      max-width: 150px;
+      right: 0;
+      top: 100%; /* Position below the action button */
+    }
+
+    .dropdown-content a {
+      display: block;
+      padding: 10px;
+      text-decoration: none;
+      color: #333;
+      text-align: center; /* Horizontally center the text */
+      width: 100%; /* Make the width 100% */
+      box-sizing: border-box; /* Include padding in the width */
+    }
+
+    .dropdown-content a:hover {
+      background-color: #ddd;
+    }
+
+    .dropdown:hover .dropdown-content {
+      display: block;
+    }
+
+    .main-content {
+      height: 80vh;
+      display: flex;
+    }
+
+    nav {
+      width: 200px;
+      background-color: #f4f4f4;
+      padding: 20px;
+      height: 80vh;
+    }
+
+    nav a {
+      display: block;
+      padding: 10px;
+      margin-bottom: 10px;
+      text-decoration: none;
+      color: #333;
+      border-radius: 5px;
+      transition: background-color 0.3s ease;
+    }
+
+    nav a:hover {
+      background-color: #ddd;
+    }
+
+    .content {
+      flex: 1;
+      padding: 20px;
+    }
+    .passwd-box {
+            width: 300px;
+            padding: 20px;
+            border: 1px solid #ccc;
+            background-color: #fff;
+            box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
+            position: absolute;
+            top: 50%;
+            left: 50%;
+            transform: translate(-50%, -50%);
+        }
+
+        input {
+            width: 100%;
+            padding: 10px;
+            margin-bottom: 10px;
+            box-sizing: border-box;
+        }
+
+        button {
+            width: 100%;
+            padding: 10px;
+            background-color: #4caf50;
+            color: #fff;
+            border: none;
+            cursor: pointer;
+        }
+
+    .info-box {
+      width: 300px;
+      padding: 20px;
+      border: 1px solid #ccc;
+      background-color: #fff;
+      box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
+      position: absolute;
+      top: 50%;
+      left: 50%;
+      transform: translate(-50%, -50%);
+    }
+  </style>
+</head>
+<body>
+
+  <header>
+    <h1>ZYM's Book Store</h1>
+    <div class="user-bar">
+      <span>Welcome, <span id="username">[Guest]</span></span>
+      <div class="action-button-container" onmouseover="showDropdown()" onmouseout="hideDropdown()">
+        <div class="action-button">Actions</div>
+        <div class="dropdown">
+          <div class="dropdown-content">
+            <a href="/login">Login</a>
+            <a href="#" onclick="(async () => { await Request('logout'); await UpdateUserInfo(); })();">Logout</a>
+            <a href="#" onclick="localStorage.removeItem('session_token'); localStorage.removeItem('outhentication_key'); localStorage.removeItem('operation_count'); window.close();">Close Session</a>
+            <a href="/register">Register</a>
+            <a href="/passwd">Change Password</a>
+            <a href="#">Admin Panel</a>
+          </div>
+        </div>
+      </div>
+    </div>
+  </header>
+
+  <div class="main-content">
+    <nav>
+      <a href="#">Search Books</a>
+      <a href="#">Purchase Books</a>
+    </nav>
+    <div class="content">
+      <div class="passwd-box">
+        <form onsubmit="console.log('trying passwd'); TryPasswd(); return false;">
+            <input id="user_name" type="text" placeholder="Username" required>
+            <input id="old_password" type="password" placeholder="Old Password" required>
+            <input id="new_password" type="password" placeholder="New Password" required>
+            <button type="submit">Reset Password</button>
+        </form>
+    </div>
+    </div>
+  </div>
+
+  <script src="/socket.io/socket.io.js"></script>
+  <script src="/communication.js"></script>
+  <script>
+    function showDropdown() {
+      document.querySelector('.dropdown-content').style.display = 'block';
+    }
+
+    function hideDropdown() {
+      document.querySelector('.dropdown-content').style.display = 'none';
+    }
+    function ChangeUsername(newUsername) {
+      document.getElementById('username').textContent = newUsername;
+    }
+    async function UpdateUserInfo(){
+      let nm=await GetMyName();
+      let pri=await GetMyPrivilege();
+      if(nm=='')
+      {
+        await RefreshSession();
+        nm=await GetMyName();
+        pri=await GetMyPrivilege();
+      }
+      if(pri==0)
+      {
+        ChangeUsername("[Guest]");
+      }
+      else if(pri==1)
+      {
+        ChangeUsername(nm);
+      }
+      else if(pri==3)
+      {
+        ChangeUsername(nm+" [Worker]");
+      }
+      else if(pri==7)
+      {
+        ChangeUsername(nm+" [Admin]");
+      }
+    }
+    document.addEventListener('SessionReady', async () => {
+      await UpdateUserInfo();
+    });
+    async function TryPasswd()
+    {
+      console.log("TryPasswd called");
+      var username = document.getElementById("user_name").value;
+      var old_password = document.getElementById("old_password").value;
+      var new_password = document.getElementById("new_password").value;
+      var ret=await Request("passwd "+username+" "+old_password+" "+new_password);
+      if(ret=="Invalid")
+      {
+        alert("Invalid username or old password");
+      }
+      else
+      {
+        // 删除注册框，在中间显示“注册成功”，三秒后自动跳转到首页
+        document.querySelector('.passwd-box').style.display = 'none';
+        document.querySelector('.content').innerHTML = '<div class="info-box"><h2>Successfully changed password</h2><p>Redirecting to home page in 3 seconds...</p></div>';
+        setTimeout(function(){window.location.href="/";},3000);
+      }
+    }
+    (async () => {
+      if((await GetMyPrivilege())<1)
+      {
+        document.querySelector('.passwd-box').style.display = 'none';
+        document.querySelector('.content').innerHTML = '<div class="info-box"><h2>Please log in first.</h2><p>Redirecting to home page in 3 seconds...</p></div>';
+        setTimeout(function(){window.location.href="/";},3000);
+      }
+    })();
+  </script>
+</body>
+</html>
\ No newline at end of file
diff --git a/frontend/Web/register.html b/frontend/Web/register.html
index e3a680f..0f95f56 100644
--- a/frontend/Web/register.html
+++ b/frontend/Web/register.html
@@ -174,7 +174,7 @@
             <a href="#" onclick="(async () => { await Request('logout'); await UpdateUserInfo(); })();">Logout</a>
             <a href="#" onclick="localStorage.removeItem('session_token'); localStorage.removeItem('outhentication_key'); localStorage.removeItem('operation_count'); window.close();">Close Session</a>
             <a href="/register">Register</a>
-            <a href="#">Change Password</a>
+            <a href="/passwd">Change Password</a>
             <a href="#">Admin Panel</a>
           </div>
         </div>
@@ -189,7 +189,7 @@
     </nav>
     <div class="content">
       <div class="register-box">
-        <form onsubmit="console.log('trying login'); TryRegister(); return false;">
+        <form onsubmit="console.log('trying register'); TryRegister(); return false;">
             <input id="user_name" type="text" placeholder="Username" required>
             <input id="password" type="password" placeholder="Password" required>
             <input id="nickname" type="text" placeholder="Nickname" required>
@@ -238,7 +238,9 @@
         ChangeUsername(nm+" [Admin]");
       }
     }
-    UpdateUserInfo();
+    document.addEventListener('SessionReady', async () => {
+      await UpdateUserInfo();
+    });
     async function TryRegister()
     {
       console.log("TryRegister called");
