Update app.py

# Bind events AFTER components exist
pdf_input.upload(
load_pdf,
inputs=[pdf_input, state],
outputs=[pdf_status, state, file_selector]
)

remove_button.click(
remove_pdf,
inputs=[file_selector, state],
outputs=[pdf_status, state, file_selector]
)

ask_button.click(
answer_question,
inputs=[question, state],
outputs=answer
)

clear_button.click(lambda: "", outputs=question)


if __name__ == "__main__":
demo.launch(
css=".clear-btn button { height: 100%; min-height: 52px; }"
)

app.py

@@ -215,29 +215,59 @@ with gr.Blocks(title="PDF Q&A Chatbot") as demo:
     })
 
     with gr.Row():
+        # LEFT COLUMN — PDF upload + removal
         with gr.Column(scale=1):
             pdf_input = gr.Files(label="Upload PDF(s)", file_types=[".pdf"])
             pdf_status = gr.Textbox(label="Status", interactive=False)
 
-            file_selector = gr.Dropdown(label="Remove a PDF", choices=[], interactive=True)
+            file_selector = gr.Dropdown(
+                label="Remove a PDF",
+                choices=[],
+                interactive=True
+            )
             remove_button = gr.Button("Remove Selected PDF")
 
+        # RIGHT COLUMN — question + clear + answer
         with gr.Column(scale=2):
             with gr.Row():
-                question = gr.Textbox(label="Your question", lines=2, scale=3)
-                clear_button = gr.Button("Clear", scale=1, min_width=80, elem_classes="clear-btn")
+                question = gr.Textbox(
+                    label="Your question",
+                    lines=2,
+                    scale=3
+                )
+                clear_button = gr.Button(
+                    "Clear",
+                    scale=1,
+                    min_width=80,
+                    elem_classes="clear-btn"
+                )
 
             answer = gr.Textbox(label="Answer", lines=8)
             ask_button = gr.Button("Ask")
 
     # Bind events AFTER components exist
-    pdf_input.upload(load_pdf, inputs=[pdf_input, state], outputs=[pdf_status, state,
+    pdf_input.upload(
+        load_pdf,
+        inputs=[pdf_input, state],
+        outputs=[pdf_status, state, file_selector]
+    )
 
-    ask_button.click(answer_question, inputs=[question, state], outputs=answer)
-    clear_button.click(lambda: "", outputs=question)
+    remove_button.click(
+        remove_pdf,
+        inputs=[file_selector, state],
+        outputs=[pdf_status, state, file_selector]
+    )
 
+    ask_button.click(
+        answer_question,
+        inputs=[question, state],
+        outputs=answer
+    )
 
+    clear_button.click(lambda: "", outputs=question)
 
 
 if __name__ == "__main__":
-    demo.launch()
+    demo.launch(
+    css=".clear-btn button { height: 100%; min-height: 52px; }"
+)