<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Login Page</title>
    <style>
        body {
            font-family: Arial, sans-serif;
            background-color: #f2f2f2;
            margin: 0;
            padding: 0;
            display: flex;
            justify-content: center;
            align-items: center;
            height: 100vh;
        }

        .login-container {
            background-color: white;
            padding: 20px;
            border-radius: 10px;
            box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
            width: 300px;
            text-align: center;
        }

        .login-container h2 {
            margin-bottom: 20px;
            color: #333;
        }

        .login-container input {
            width: 100%;
            padding: 10px;
            margin: 10px 0;
            border: 1px solid #ddd;
            border-radius: 5px;
        }

        .login-container input[type="submit"] {
            background-color: #4CAF50;
            color: white;
            border: none;
            cursor: pointer;
        }

        .login-container input[type="submit"]:hover {
            background-color: #45a049;
        }

        .error {
            color: red;
            font-size: 14px;
        }
    </style>
</head>
<body>

<div class="login-container">
    <h2>Login</h2>
    <form action="#" method="post" onsubmit="return validateForm()">
        <div>
            <input type="text" id="username" name="username" placeholder="Username" required>
            <div class="error" id="usernameError"></div>
        </div>
        <div>
            <input type="password" id="password" name="password" placeholder="Password" required>
            <div class="error" id="passwordError"></div>
        </div>
        <div>
            <input type="submit" value="Login">
        </div>
    </form>
</div>

<script>
    function validateForm() {
        var username = document.getElementById("username").value;
        var password = document.getElementById("password").value;
        var usernameError = document.getElementById("usernameError");
        var passwordError = document.getElementById("passwordError");

        // Reset error messages
        usernameError.textContent = "";
        passwordError.textContent = "";

        // Validate username and password
        if (username === "") {
            usernameError.textContent = "Username is required.";
            return false;
        }
        if (password === "") {
            passwordError.textContent = "Password is required.";
            return false;
        }

        // If no errors, form is valid
        return true;
    }
</script>

</body>
</html>
