I'm building a custom eCommerce store(shopping cart), I'm using ajax(jquery)
to post the Add to Cart button when clicked so the page doesn't have to
be refreshed, after submitting, the cart is updated and a message is generated by the server-side
script which I display in a div on the page using

$("#message-div").html(data);

Now, how do I make this message appear in a pop up
modal dialog instead of that div.

2. how do I display the new updated cart
info on the same page (without refreshing).

Thanks.