added px to height value

app.py

@@ -91,7 +91,7 @@ with gr.Blocks(title=title) as demo:
     
     with gr.Column(variant="compact"):
         gr.Markdown("## Results")
-        gallery = gr.Gallery(label="found images", show_label=True, elem_id="gallery", columns=[2], rows=[4], object_fit="contain", height="400", preview=True)
+        gallery = gr.Gallery(label="found images", show_label=True, elem_id="gallery", columns=[2], rows=[4], object_fit="contain", height="400px", preview=True)
         gr.Markdown("Information of the found images")
         df = gr.DataFrame()
     btn.click(main, [query, n_s], [gallery, df])