Add custom 404 and 500 error handlers with corresponding templates

core/templates/404.html

@@ -0,0 +1,14 @@
+{% extends "base.html" %}
+
+{% block content %}
+<div class="row justify-content-center">
+    <div class="col-md-8 text-center">
+        <div class="alert-danger mt-5">
+            <h1 class="display-1">404</h1>
+            <h2>Page Not Found</h2>
+            <p class="lead">The page you're looking for doesn't exist or has been moved.</p>
+            <p>Check the URL or return to the <a href="{% url 'index' %}" class="alert-link">homepage</a>.</p>
+        </div>
+    </div>
+</div>
+{% endblock content %}