Revert Gradio 6.x config: move theme/css back to Blocks for 5.x compat

app.py

@@ -938,6 +938,8 @@ def build_ui():
 
     with gr.Blocks(
         title="AI Research Paper Analyst",
+        theme=gr.themes.Default(primary_hue="blue", secondary_hue="slate"),
+        css=".main-header {text-align: center; margin-bottom: 2rem;} .upload-area {min-height: 150px;}"
     ) as app:
 
         gr.Markdown(
@@ -1051,7 +1053,4 @@ if __name__ == "__main__":
 
     # Launch with environment variables handling port/host
     ui = build_ui()
-    ui.launch(
-        theme=gr.themes.Default(primary_hue="blue", secondary_hue="slate"),
-        css=".main-header {text-align: center; margin-bottom: 2rem;} .upload-area {min-height: 150px;}"
-    )
+    ui.launch()