[HTML] ДОМАШНО ТАБЛИЦИ - ЗАДАЧА 4

<!DOCTYPE html>  // css file - http://pastebin.com/KMYw3Uvw
                // забележка : запишете го с име calcStyle.css
<html lang="en">
    <head>
        <meta charset="utf-8" />
        <title>04. Calculator</title>
        <meta name="description" content="" />
        <meta name="author" content="Ventsislav" />
        <meta name="viewport" content="width=device-width; initial-scale=1.0" />
        <link href="style/calcStyle.css" rel="stylesheet" type="text/css" />
    </head>
    <body>
        <div>
            <form action="" method="post">
                <table border="1" cellspacing="0" cellpadding="0">
                    <tr>
                        <td colspan="4">
                            <textarea id="result" dir="rtl">123</textarea>
                        </td>
                    </tr>
                    <tr>
                        <td>
                        <input type="button" value="1" />
                        </td>
                        <td>
                        <input type="button" value="2" />
                        </td>
                        <td>
                        <input type="button" value="3" />
                        </td>
                        <td>
                        <input type="button" value="+" />
                        </td>
                    </tr>
                    <tr>
                        <td>
                        <input type="button" value="4" />
                        </td>
                        <td>
                        <input type="button" value="5" />
                        </td>
                        <td>
                        <input type="button" value="6" />
                        </td>
                        <td>
                        <input type="button" value="-" />
                        </td>
                    </tr>
                    <tr>
                        <td>
                        <input type="button" value="7" />
                        </td>
                        <td>
                        <input type="button" value="8" />
                        </td>
                        <td>
                        <input type="button" value="9" />
                        </td>
                        <td>
                        <input type="button" value="*" />
                        </td>
                    </tr>
                    <tr>
                        <td colspan="2">
                        <input type="button" id="zero" value="0"/>
                        </td>
                        <td>
                        <input type="button" value="." />
                        </td>
                        <td>
                        <input type="button" value="/" />
                        </td>
                    </tr>
                </table>
            </form>
        </div>
    </body>
</html>