Let Gradio own its port on Spaces so frontend assets load

app.py

@@ -446,12 +446,19 @@ def serve_via_gradio() -> None:
     with _launch_lock:
         rt = build_runtime()
 
-    demo.launch(
-        server_name="0.0.0.0",
-        server_port=int(os.environ.get("APP_PORT") or 7860),
-        prevent_thread_lock=True,  # returns so we can attach routes
-        show_api=False,
-    )
+    # On a Space, let Gradio use its own env-driven defaults (GRADIO_SERVER_PORT
+    # and the Space root path). Forcing a port breaks the frontend asset URLs
+    # behind HF's proxy: the CSS/JS 404, no JavaScript runs, and the page never
+    # leaves its initial server-rendered state. That looks exactly like "the
+    # dashboard shows nothing" -- demo.load never fires, so the sign-in token in
+    # the query string is never read.
+    launch_kwargs: dict = {"prevent_thread_lock": True, "show_api": False}
+    if port := os.environ.get("APP_PORT"):
+        # Self-hosting / local dev, where nothing sets GRADIO_SERVER_PORT.
+        launch_kwargs["server_name"] = "0.0.0.0"
+        launch_kwargs["server_port"] = int(port)
+
+    demo.launch(**launch_kwargs)  # returns so we can attach routes
 
     # demo.app only exists once launched.
     demo.app.state.rt = rt