add "scroll to top" button

[sambedan1]

1-Implement a "Scroll to Top" button that appears when users scroll down the page.
2-Ensure the button is easily visible and matches the website's design.
3-Make the button functional, allowing smooth scrolling back to the top of the page when clicked.
please assign this task to me

[simmi-verma]

I would like to work on it . Please assign to me . Can you add label gssoc-ext 24.

[samyakmaitre]

Issue already under #41