Customize the Django admin to differentiate environments

We often have the same website running in different configurations:

• Once as a production site.
• Once as a place where editors update and preview the content. The content is later automatically (and maybe partially) transferred from this environment to the production environment.
• Once as a stage environment to stabilize the code.
• And maybe additional environments for local development.

The Django admin panel mainly uses CSS variables for styling since theming support was introduced in Django 3.2 (by yours truly with a lot of help from others). This makes it simple and fun to customize the colors of all interface elements in a straightforward way without having to write loads of CSS.

If you have a ENVIRONMENT context variable available (as we do) you could add the following template as admin/base.html to your project, giving you a red color scheme for the production environment (to discourage people from updating content) and a nice scheme for the preproduction environment which clearly deviates from the standard color scheme used everywhere else:

{% block extrahead %}
  {{ block.super }}
  <style>
#site-name::after {
  content: " ({{ ENVIRONMENT }})";
  font-size: 60%;
}
  </style>
  {% if ENVIRONMENT == 'production' %}
    <style>
:root {
  --primary: #aa0000;
  --secondary: #810000;
  --accent: yellow;
}
    </style>
  {% elif ENVIRONMENT == 'preproduction' %}
    <style>
:root {
  --primary: #30b181;
  --secondary: #1f7957;
  --accent: #cdffea;
}
    </style>
  {% endif %}
{% endblock %}