diff --git a/ragna/deploy/_ui/central_view.py b/ragna/deploy/_ui/central_view.py
index 0e61f5ff..d28bf07b 100644
--- a/ragna/deploy/_ui/central_view.py
+++ b/ragna/deploy/_ui/central_view.py
@@ -142,7 +142,7 @@ def _update_object_pane(self, event=None):
             self._object_panel = self._center_row[0] = pn.Column(
                 self._object_panel,
                 self._copy_and_source_view_buttons(),
-                css_classes=[css_class],
+                css_classes=["message", css_class],
                 stylesheets=ui.stylesheets(
                     (f":host(.{css_class})", self._content_style_declarations)
                 ),