diff --git a/auth_cookie.php b/auth_cookie.php
new file mode 100644
index 0000000..e0b1bd1
--- /dev/null
+++ b/auth_cookie.php
@@ -0,0 +1,29 @@
+<?php
+session_start();
+if (isset($_COOKIE['login_time']) && isset($_COOKIE['username'])) {
+    header("Location: welcome.php");
+    exit();
+}
+?>
+<!DOCTYPE html>
+<html lang="">
+<head>
+    <title>Login</title>
+</head>
+<body>
+    <?php if (isset($_GET['error'])): ?>
+        <p style="color: red;">
+            <?php 
+            if ($_GET['error'] === 'invalid') echo "Invalid credentials!";
+            if ($_GET['error'] === 'expired') echo "Session expired!";
+            ?>
+        </p>
+    <?php endif; ?>
+    
+    <form action="do_login.php" method="post">
+        Username: <input type="text" name="username"><br>
+        Password: <input type="password" name="password"><br>
+        <input type="submit" value="Login">
+    </form>
+</body>
+</html>
diff --git a/do_login.php b/do_login.php
new file mode 100644
index 0000000..b187136
--- /dev/null
+++ b/do_login.php
@@ -0,0 +1,19 @@
+<?php
+session_start();
+// 简单验证（实际应使用数据库和密码哈希）
+$valid_username = 'admin';
+$valid_password = 'password';
+
+$username = $_POST['username'] ?? '';
+$password = $_POST['password'] ?? '';
+
+if ($username === $valid_username && $password === $valid_password) {
+    $login_time = time();
+    // 设置Cookie（60秒有效期）
+    setcookie('username', $username, $login_time + 60, '/');
+    setcookie('login_time', $login_time, $login_time + 60, '/');
+    header("Location: welcome.php");
+} else {
+    header("Location: auth_cookie.php?error=invalid");
+}
+exit();
diff --git a/logout.php b/logout.php
new file mode 100644
index 0000000..01ab30c
--- /dev/null
+++ b/logout.php
@@ -0,0 +1,8 @@
+<?php
+session_start();
+// 清除Cookie
+setcookie('username', '', time() - 3600, '/');
+setcookie('login_time', '', time() - 3600, '/');
+header("Location: login.php");
+exit();
+?>
\ No newline at end of file
diff --git a/welcome.php b/welcome.php
new file mode 100644
index 0000000..06a7880
--- /dev/null
+++ b/welcome.php
@@ -0,0 +1,36 @@
+<?php
+session_start();
+// 验证Cookie
+if (!isset($_COOKIE['login_time']) || !isset($_COOKIE['username'])) {
+    header("Location: login.php");
+    exit();
+}
+
+$current_time = time();
+$login_time = (int)$_COOKIE['login_time'];
+$remaining = 60 - ($current_time - $login_time);
+
+if ($remaining <= 0) {
+    // 清除过期Cookie
+    setcookie('username', '', time() - 3600, '/');
+    setcookie('login_time', '', time() - 3600, '/');
+    header("Location: login.php?error=expired");
+    exit();
+}
+?>
+<!DOCTYPE html>
+<html>
+<head>
+    <title>Welcome</title>
+</head>
+<body>
+<h2>Welcome <?php echo htmlspecialchars($_COOKIE['username']); ?>!</h2>
+<p>Session expires in: <?php echo $remaining; ?> seconds</p>
+<a href="logout.php">Logout</a>
+
+<script>
+    // 自动刷新剩余时间
+    setTimeout(() => location.reload(), 1000);
+</script>
+</body>
+</html>
