Placeholder Shown
HTML
<div>
<input id="my_input" placeholder="placeholder" type="text">
<label for="my_input">My Label</label>
</div>
JavaScript
$("#my_input").on("keydown keypress keyup paste", function () {
var textColor = $(this).val() ? "red" : "green";
$("div label").css({"color" : textColor});
});