Improve expired session and CSRF error handling

app/templates/error.html

@@ -6,7 +6,7 @@
 {% endblock %}
 
 {% block content %}
-<div class="centered primary-color">
-    <h1>{{ title }}</h1>
+<div class="centered primary-color box">
+    <h1 class="error-title">{{ title | safe }}</h1>
 </div>
 {% endblock %}