<input class="button" type="submit" value="TIKLA"/>

input[type="submit"]{display: inline-block; background: #00FF99; padding:20px; border-bottom:4px solid #00CC00; color:#00CC99; text-decoration:none; margin-bottom:20px; cursor:pointer;}

$(".button").click(function(){
  $("input:submit").val("W3TR");
});