Design and implement a Web page named esp.html that allows the user to conduct an ESP test. Your page should look something like the one in Figure 11.14. The rectangle containing a question mark represents the back of a card that is associated with a particular shape. After contemplating which shape appears on the front of the card, the user clicks the button corresponding to the shape he or she believes is on the card (here, four possibilities are assumed). After each guess, the question mark should be replaced by a randomly selected shape, and an alert box should notify the user as to whether the guess was correct. Statistics concerning the number and percentage of correct guesses should be maintained in text spans. After the statistics have been updated and the alert box has been closed, the page should restore the question-mark image, enabling the user to enter another guess.

Although you can create your own images for the cards, you can also use the images provided for you in the balance3e.com/Images directory. This directory contains images of four shapes- square.gif, triangle.gif, circle.gif, and star.gif-as well as mystery.gif, which displays the question mark?