Update app.py

app.py

@@ -129,7 +129,7 @@ with col1:
     st.markdown(
         """
         <div class="tooltip">
-            <input type="text" placeholder="Enter function" readonly style="border: none; color: transparent; background-color: transparent;">
+            <input type="text" readonly style="border: none; color: transparent; background-color: transparent;">
             <span class="tooltiptext">
                 **How to input your function:**
                 - Use `x` for the variable.