Add a little grabby corner to resize the super-imposed plots

Ordinary plot

<img width="358" height="315" alt="Image" src="https://github.com/user-attachments/assets/24cc173d-404f-4bbe-a429-9eda9ca53a7d" />

Super-imposed plot

<img width="409" height="338" alt="Image" src="https://github.com/user-attachments/assets/7e063d9b-d9cd-4223-b03e-bd023dfc996c" />