<!DOCTYPE html>
<html>
<head>
<script type='text/javascript'
src='http://code.jquery.com/jquery-1.8.3.js'></script>
<style type='text/css'>
#id2 .mycolor {
color: white;
background-color: red;
}
#id3:active {
color: red;
background-color: white;
}
</style>
<script type='text/javascript'>
$(function(){
$('#id2').find('span').addClass('mycolor');
});
</script>
</head>
<body>
<div id="id2">
<span>Demo</span>
</div>
</body>
</html>