templates/login.html

{% extends "base.html" %}
{% block title %}Login{% endblock %}
{% block content %}
<h2>Login</h2>
<form method="POST" class="form-box">
    <input type="text" name="username" placeholder="Username" required><br>
    <input type="password" name="password" placeholder="Password" required><br>
    <button type="submit">Login</button>
</form>
<p>Don't have an account? <a href="/signup">Signup</a></p>
{% endblock %}