Our cart is now fully functional, and as such we could leave it as is. However, when clicking the Add to cart button, there is no feedback as to whether or not something happened. Some online shops take you to the shopping cart page as and when you add a product to your cart, and if that's your preferred approach, then it should be a fairly simple change for you to add a page change as part of the button click handler. However, to demonstrate a different approach, we'll use a library called toastr to provide instant feedback to the user that something positive happened.

First, we need to download a new npm module. The original toastr library has a dependency on jQuery, so instead we&apos...