django-grappelli import_export buttons not being styled

base.html

{% extends "admin/base_site.html" %}
{% load i18n admin_static admin_modify %}
{% load admin_urls %}
{% load url from future %}

{% block bodyclass %}{{ opts.app_label }}-{{ opts.object_name.lower }} change-form{% endblock %}
{% if not is_popup %}
{% block breadcrumbs %}
<ul>
    <li><a href="{% url 'admin:index' %}">{% trans 'Home' %}</a></li>
    {% if title %}
        <li> &rsaquo; {{ title }}</li>
    {% endif %}
    <li><a href="{% url 'admin:app_list' app_label=opts.app_label %}">{{ opts.app_label|capfirst|escape }}</a></li>
    <li><a href="{% url opts|admin_urlname:'changelist' %}">{{ opts.verbose_name_plural|capfirst }}</a></li>
    <li> {% block breadcrumbs_last %}{% endblock %}</li>
</ul>

{% endblock %}
{% endif %}

change_list.html

{% extends "admin/change_list.html" %}

{# Original template renders object-tools only when has_add_permission is True. #}
{# This hack allows sub templates to add to object-tools #}
{% block object-tools %}
  <ul class="grp-object-tools">
    {% block object-tools-items %}
      {% if has_add_permission %}
        {{ block.super }}
      {% endif %}
    {% endblock %}
  </ul>
{% endblock %}

export.html

{% extends "admin/import_export/base.html" %}
{% load url from future %}
{% load i18n %}
{% load admin_urls %}
{% load import_export_tags %}

{% block breadcrumbs_last %}
{% trans "Export" %}
{% endblock %}

{% block content %}
<h1>{% trans "Export" %}</h1>

<form action="" method="POST">
  {% csrf_token %}
  <div>
        {% for field in form %}
          <div class="grp-form-row">
            <fieldset class="grp-module">
              <div class="grp-row grp-cells-1 {% if field.errors %} grp-errors{% endif %}">
                  {% if field.errors %}
                      <p class="errornote">{% trans "Please correct the error below." %}</p>
                      <ul class="errorlist"><li> {{ field.errors }}</li></ul>
                  {% endif %}

                <div class="c-1">{{ field.label_tag }}</div>
                <div class="c-2">{{ field }}
                  {% if field.field.help_text %}
                    <p class="grp-help">{{ field.field.help_text|safe }}</p>
                  {% endif %}
                </div>
              </div>
            </fieldset>
          </div>
        {% endfor %}

      <footer class="grp-module grp-submit-row grp-fixed-footer">
          <header style="display:none"><h1>Submit Options</h1></header>
        <ul>
          <li><input type="submit" value="{% trans 'Download' %}" class="grp-button grp-default" /></li>
        </ul>
      </footer>
  </div>
</form>
{% endblock %}