Fix success message style
{% block content %}
{% if submitted %}
- <ul>
- <li class="messagelist">
-
+ <ul class="messagelist">
+ <li class="success">
Your message was submitted successfully. Thank you.
</li>
</ul>
+ <p class="success">
+ </p>
{% else %}
<form action="{% url 'admin:newsletters_subscription_changelist' %}" method="post">
