diff --git a/note_kfet/templates/400.html b/note_kfet/templates/400.html
index 35606525..89d7ba85 100644
--- a/note_kfet/templates/400.html
+++ b/note_kfet/templates/400.html
@@ -1,8 +1,22 @@
 {% extends "base.html" %}
-
+{% comment %}
+SPDX-License-Identifier: GPL-3.0-or-later
+{% endcomment %}
 {% load i18n %}
 
 {% block content %}
-    <h1>{% trans "Bad request" %}</h1>
-    {% blocktrans %}Sorry, your request was bad. Don't know what could be wrong. An email has been sent to webmasters with the details of the error. You can now drink a coke.{% endblocktrans %}
+<div class="card text-white bg-secondary">
+    <h3 class="card-header text-center">
+        {% trans "Bad request" %}
+    </h3>
+    <div class="card-body">
+        <p>
+            {% blocktrans trimmed %}
+            Sorry, your request was bad. Don't know what could be wrong.
+            An email has been sent to webmasters with the details of the error.
+            You can now drink a coke.
+            {% endblocktrans %}
+        </p>
+    </div>
+</div>
 {% endblock %}
\ No newline at end of file
diff --git a/note_kfet/templates/403.html b/note_kfet/templates/403.html
index 317865f2..5256e32d 100644
--- a/note_kfet/templates/403.html
+++ b/note_kfet/templates/403.html
@@ -1,13 +1,19 @@
 {% extends "base.html" %}
-
+{% comment %}
+SPDX-License-Identifier: GPL-3.0-or-later
+{% endcomment %}
 {% load i18n %}
 
 {% block content %}
-    <h1>{% trans "Permission denied" %}</h1>
-    {% blocktrans %}You don't have the right to perform this request.{% endblocktrans %}
-    {% if exception %}
-        <div>
-            {% trans "Exception message:" %} {{ exception }}
-        </div>
-    {% endif %}
+<div class="card text-white bg-secondary">
+    <h3 class="card-header text-center">
+        {% trans "Permission denied" %}
+    </h3>
+    <div class="card-body">
+        <p>{% blocktrans %}You don't have the right to perform this request.{% endblocktrans %}</p>
+        {% if exception %}
+        <p>{% trans "Exception message:" %} {{ exception }}</p>
+        {% endif %}
+    </div>
+</div>
 {% endblock %}
\ No newline at end of file
diff --git a/note_kfet/templates/404.html b/note_kfet/templates/404.html
index 8477f914..03b81658 100644
--- a/note_kfet/templates/404.html
+++ b/note_kfet/templates/404.html
@@ -1,13 +1,23 @@
 {% extends "base.html" %}
-
+{% comment %}
+SPDX-License-Identifier: GPL-3.0-or-later
+{% endcomment %}
 {% load i18n %}
 
 {% block content %}
-    <h1>{% trans "Page not found" %}</h1>
-    {% blocktrans %}The requested path <code>{{ request_path }}</code> was not found on the server.{% endblocktrans %}
-    {% if exception != "Resolver404" %}
-        <div>
-            {% trans "Exception message:" %} {{ exception }}
-        </div>
-    {% endif %}
+<div class="card text-white bg-secondary">
+    <h3 class="card-header text-center">
+        {% trans "Page not found" %}
+    </h3>
+    <div class="card-body">
+        <p>
+            {% blocktrans trimmed %}
+            The requested path <code>{{ request_path }}</code> was not found on the server.
+            {% endblocktrans %}
+        </p>
+        {% if exception != "Resolver404" %}
+        <p>{% trans "Exception message:" %} {{ exception }}</p>
+        {% endif %}
+    </div>
+</div>
 {% endblock %}
\ No newline at end of file
diff --git a/note_kfet/templates/500.html b/note_kfet/templates/500.html
index 50b62bc2..fb7d1c69 100644
--- a/note_kfet/templates/500.html
+++ b/note_kfet/templates/500.html
@@ -1,8 +1,22 @@
 {% extends "base.html" %}
-
+{% comment %}
+SPDX-License-Identifier: GPL-3.0-or-later
+{% endcomment %}
 {% load i18n %}
 
 {% block content %}
-    <h1>{% trans "Server error" %}</h1>
-    {% blocktrans %}Sorry, an error occurred when processing your request. An email has been sent to webmasters with the detail of the error, and this will be fixed soon. You can now drink a beer.{% endblocktrans %}
+<div class="card text-white bg-secondary">
+    <h3 class="card-header text-center">
+        {% trans "Server error" %}
+    </h3>
+    <div class="card-body">
+        <p>
+            {% blocktrans trimmed %}
+            Sorry, an error occurred when processing your request.
+            An email has been sent to webmasters with the detail of the error,
+            and this will be fixed soon. You can now drink a beer.
+            {% endblocktrans %}
+        </p>
+    </div>
+</div>
 {% endblock %}
\ No newline at end of file