Peer to peer code review

## Suggestions

Great work on implementing the project. The design looks good and the functionality is working as expected. However, I think it would be an excellent addition to make the page responsive for smaller screen sizes, such as mobiles.

You can add media queries to your `index.css` file to implement this.

Start with index.css and review the current page layout and styles for narrow mobile screen sizes. Add responsive behavior using media queries, then verify that the book manager remains usable on smaller screens and that the existing desktop layout still works.

Written by the indexing model from the issue text.