When text is entered correctly, image lights up/changes?

Ok, here is what I am trying to do, here is a preview of my design from Photoshop that I did or view attachment if the link does not work : http://japanesefriend.zxq.net/webapp/hiraganaquiz2.jpg

I am trying to have it when the user types in box the correct pronunciation for the Japanese symbol light up/change “images”. Because regular text is a bit boring, I basically want the image to rollover/change to to red like in my preview above when the correct text is entered in the box. So again, for example

なまえ

 when “na” is typed, i wish to have the image of "な” change. Here is a code I have, but I cannot figure out how to have images instead of just text? If you have any additional code/text I would greatly appreciate it! Thank you so much.

Sincerely,
Anthony

Instead of changing the background color, how about changing a background-image?

Yes, that’s exactly what I need. Take a look at this preview/set up here. http://jsfiddle.net/adeneo/PT523/3/
My main problem is I am not sure exactly where all the codes are supposed to go/what order. Can someone set up the a document/the right order for me so I can understand? Thanks!

HTML

<ul>
    <li><img src="http://files.sharenator.com/grumpy_cat_Grumpy_Cats-s492x305-51794-580.jpg" />na</li>
    <li><img src="http://sleepycathollow.files.wordpress.com/2010/09/funny-pictures-cat-is-grumpy.jpg?w=500&h=374" />ma</li>
    <li><img src="http://www.adoptapetfenton.com/userfiles/grumpy%20cat.jpg" />ba</li>
<ul>

<br /><br />

<input type="text" id="test" />

<br /><br />
Type the text in the boxes into the input, and see them change.
    

Javascript

var text = ['na', 'ma', 'ba'];

var happy = ['http://1.bp.blogspot.com/_QQ6fUQG95io/TUYo-3Crs-I/AAAAAAAAAAM/o9kvQGaaKps/s1600/675_smiling+cat.gif',
             'http://www.all4humor.com/images/files/Cat%20Smiling%20Huge.jpg',
             'http://img.photobucket.com/albums/v607/yrduckie/Emoticons/CatKittySmiley-1.jpg'
            ];

var grumpy = $('img').map(function(){ return this.src; }).get(); //gets the original images from the HTML

$("#test").on('keyup', function() {
    var typed = this.value;
    $.each(text, function(index, item) {
        if (typed.indexOf(item)!=-1) {
            $('li', 'ul').eq(index).find('img').attr('src', happy[index]);
        }else{
            $('li', 'ul').eq(index).find('img').attr('src', grumpy[index]);
        }
    });
});

CSS

li {position: relative; height: 100px; width: 160px; display: inline-block; background: red; text-align: center; vertical-align: middle; margin: 20px;}

img {height: 100px; width: 160px;}