flaskbb/flaskbb/templates/errors/page_not_found.html

{% set page_title = _("Oh noes! 404") %}

{% extends theme("layout.html") %}
{% block content %}

<div class="panel page-panel">
    <div class="panel-body page-body">
        <div class="col-md-12 col-sm-12 col-xs-12">
            <h1>{% trans %}Oops, Page not found!{% endtrans %}</h1>
            <p>{% trans %}The page you were looking for does not exist.{% endtrans %}</p>
            <p><a href="{{url_for('forum.index')}}">{% trans %}Back to the Forums{% endtrans %}</a></p>
        </div>
    </div>
</div>

{% endblock %}