index.html

<!DOCTYPE html>
<html>
    <head>
        <meta charset="utf-8" />
        <link rel="stylesheet" href="index.css">
    </head>
    <body>
        <h2>Paint fill effect with flood fill</h2>
        <table width="100%"></table>
        <form>
            <textarea id="matrix" 
                rows="10" 
                cols="50">
                Y,Y,Y,G,G,G,G,G,G,G
                Y,Y,Y,Y,Y,Y,G,V,V,V
                G,G,G,G,G,G,G,V,V,V
                W,W,W,W,W,G,G,G,G,V
                W,R,R,R,R,R,G,V,V,V
                W,W,W,R,R,G,G,V,V,V
                W,B,W,R,R,R,R,R,R,V
                W,B,B,B,B,R,R,V,V,V
                W,B,B,V,B,B,B,B,V,V
                W,B,B,V,V,V,V,V,V,V
            </textarea>
            <input id="replacement" type="text" value="B">
        </form>
        <script src="bundle.js"></script>
    </body>
</html>