Update app.py

app.py

@@ -67,9 +67,12 @@ with gr.Blocks(theme=gr.themes.Soft(), css="""
         display: flex;
         align-items: center;
     }
+    #text-input {
+        flex-grow: 1;
+    }
 """) as app:
     with gr.Row(elem_id="row"):
-        text_input = gr.Textbox(label="Your message", placeholder="Type your message...", lines=1, max_lines=1, css_classes="flex-grow")
+        text_input = gr.Textbox(label="Your message", placeholder="Type your message...", lines=1, max_lines=1, elem_id="text-input")
         submit_btn = gr.Button(
             "send",
             variant="primary",