Corrijo urlpatterns

gestion_reservas/gestion_reservas/urls.py

@@ -38,5 +38,9 @@ urlpatterns = [
     path('api/proximo-evento/', views.proximo_evento, name='proximo_evento'),
     path('api/todos-los-eventos/', views.todos_los_eventos, name='todos_los_eventos'),
 
-] + static(settings.MEDIA_URL, document_root=settings.MEDIA_ROOT)
+]
+
+if settings.DEBUG:
+    urlpatterns += static(settings.STATIC_URL, document_root=settings.STATIC_ROOT)
+    urlpatterns += static(settings.MEDIA_URL, document_root=settings.MEDIA_ROOT)