diff --git a/atlas/templates/atlas/series_viewer.html b/atlas/templates/atlas/series_viewer.html
index a922d207..599814a7 100755
--- a/atlas/templates/atlas/series_viewer.html
+++ b/atlas/templates/atlas/series_viewer.html
@@ -124,7 +124,7 @@
                         {% include 'atlas/partials/series_cases_list.html' %}
                     </div>
                     {% if can_edit %}
-                        <details class="mt-2">
+                        <details id="add-series-to-case-details" class="mt-2">
                             <summary>Add Series to Case</summary>
                             <form hx-post="{% url 'atlas:add_series_to_case' series.pk %}" hx-target="#cases-list" hx-swap="innerHTML" class="mt-2">
                                 {% csrf_token %}
@@ -138,7 +138,7 @@
                                 </div>
                                 <div class="d-flex gap-2">
                                     <button type="submit" class="btn btn-primary btn-sm">Add to Case</button>
-                                    <button type="button" class="btn btn-outline-secondary btn-sm" data-bs-toggle="collapse" data-bs-target=".mt-2">Close</button>
+                                    <button type="button" class="btn btn-outline-secondary btn-sm" onclick="document.getElementById('add-series-to-case-details').open = false">Close</button>
                                 </div>
                             </form>
                         </details>