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<!DOCTYPE html>
         <html>
         <head>
         <meta charset="utf-8">
         <title>Login</title>
         <link rel="stylesheet" href="css/style.css"/>
         </head>
         <body>
         <?php
            require('db.php');
            session_start();

           if (isset($_POST['username'])){
           $username = $_REQUEST['username'];
           $password = $_REQUEST['password'];

           $sql = "SELECT * FROM `users` WHERE username='$username' and
            password='".md5($password)."'";
           $result = $conn->query($sql) or die(mysqli_error());
           if($result->num_rows > 0){
           $_SESSION['username'] = $username;
           header("Location: index.php"); //Redirect user to index.php
           }else{
                 echo "<div class='form'><h3>Username/password is
                  incorrect.</h3><br>Click here to <a
                  href='login.php'>Login</a></div>";
           }
           }else{
           ?>
           <div class="form">
        <h1>Log In</h1>
        <form action="" method="post" name="login">
        <input type="text" name="username" placeholder="Username"
          required />
        <input type="password" name="password" placeholder="Password"
         required />
        <input name="submitted" type="submit" value="Login" />
        </form>
        <p>Not registered yet? <a href='registration.php'>Register
        Here</a></p>

        </div>
            <?php } ?>

       </body>
       </html>