Untitled

<!DOCTYPE HTML>
<html>
<body>
<link type="text/css" rel="stylesheet" href="example.css">

<div class="d1" onclick="highlight(this)">1
    <div class="d2" onclick="highlight(this)">2
        <div class="d3" onclick="highlight(this)">3
        </div>
    </div>
</div>

<script>
function highlight(elem) {
    elem.style.backgroundColor='yellow'
    alert(elem.className)
    elem.style.backgroundColor = ''
}
</script>

</body>
</html>