[PYTHON] Implemented Django bulletin board function and menu bar

I wanted to take a break to make a schedule, so I implemented a menu bar and created a bulletin board. First, modify the login screen a little

accounts/login.html



{% load static %}


{% block customcss %}
    <link rel='stylesheet' type='text/css' href="{% static 'accounts/login.css' %}">
{% endblock customcss %}


{% block header %}
{% endblock header %}

{% block content %}
  <body>
    <form class="form-login" action='' method='POST'>
    <h1>GK</h1>
    <h1>Login</h1>
    {% csrf_token %}

    {{ form.as_p }}

    <button>Login</button>
    <p class="mt-5 mb-3 text-muted">&copy;GK</p>
    </form>
  </body>
{% endblock content %}
</html>

Css has diverted BootStarp.


#### **`accounts/login.css`**
```css