Update app.py

app.py

@@ -36,7 +36,7 @@ app.layout = dbc.Container([
             ),
             dbc.Input(id="url-input", placeholder="Or enter PDF URL", type="text", className="mt-3"),
             dbc.Button("Compress", id="compress-btn", color="primary", className="mt-3"),
-            dbc.Spinner(html.Div(id="compression-status"), color="primary", type="grow", className="mt-3"),
+            dbc.Spinner(html.Div(id="compression-status"), color="primary", type="grow", spinner_class_name="mt-3"),
             dcc.Download(id="download-pdf"),
             dbc.Button("Download Compressed PDF", id="download-btn", color="success", className="mt-3", disabled=True),
         ])