Update app.py

app.py

@@ -399,12 +399,15 @@ js_code = """
         );
         
         const chatbox = document.getElementById('component-2');
+        const buttonImg = document.getElementById('custom-btn');
         if (chatbox.style.transform === 'scaleY(0)') {
             chatbox.style.transform = 'scaleY(1)'; 
             chatbox.style.opacity = '1';
+            buttonImg.src = "/file=bot.png";
         } else {
             chatbox.style.transform = 'scaleY(0)';
             chatbox.style.opacity = '0';
+            buttonImg.src = "/file=message.png";
         }
     }