Rewrite template.

aleksis/apps/untis/templates/untis/untis_import.html

 {# -*- engine:django -*- #}
 
 {% extends "core/base.html" %}
-{% load bootstrap4 i18n static %}
 
-{% block bootstrap4_title %}{% blocktrans %}Import Untis data{% endblocktrans %} - {{ block.super }}{% endblock%}
+{% load material_form i18n %}
 
-{% block page_title %}Import Untis data{% endblock %}
+
+{% block page_title %}{% blocktrans %}Import Untis data{% endblocktrans %}{% endblock %}
 
 {% block content %}
-  <div class="jumbotron">
-    <p class="lead">
-      {% blocktrans %}
-        Untis provides a function for exporting all data as an XML file.
-      {% endblocktrans %}
-    </p>
-    <div class="alert alert-danger" role="alert">
-      <span class="mdi mdi-alert"></span>
+
+  <p class="lead">
+    {% blocktrans %}
+      Untis provides a function for exporting all data as an XML file.
+    {% endblocktrans %}
+  </p>
+  <div class="alert error">
+    <p>
+      <i class="material-icons left">error</i>
       {% blocktrans %}
         Newly imported data will be valid as of tomorrow.
       {% endblocktrans %}
@@ -30,15 +31,13 @@
       {% blocktrans %}
         Teachers, rooms, subjects and classes and periods will be updated in place.
       {% endblocktrans %}
-    </div>
+   </p>
   </div>
 
   <form method="post" enctype="multipart/form-data">
     {% csrf_token %}
-    {% bootstrap_form upload_form %}
-
-    <button type="submit" class="btn btn-dark">
-      {% blocktrans %}Process{% endblocktrans %}
-    </button>
+    {% form form=upload_form %}{% endform %}
+    {% include "core/save_button.html" %}
   </form>
+
 {% endblock %}