<!DOCTYPE html>
<html>
<head>
<script src="/lib/jquery-1.12.2.min.js"></script>
<script>
$(document).ready(function(){
    $(".field").change(function(){
        $(this).css("background-color", "#D6D6FF");
    });
});
</script>
</head>
<body>

<p>Attach a function to run when an element has been changed:</p>

Enter your name: <input class="field" type="text">
<p>Write something in the input field, and then press enter or click outside the field.</p>

Car:
<select class="field" name="cars">
  <option value="volvo">Volvo</option>
  <option value="saab">Saab</option>
  <option value="fiat">Fiat</option>
  <option value="audi">Audi</option>
</select>

<p>Select an option in the drop-down list.</p>

</body>
</html>