<!DOCTYPE html>
<html>
<head>
<title>Title of the Document</title>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.5.0/jquery.min.js"></script>
<style>
.green {
color: green;
}
</style>
</head>
<body>
<div>
<span>Welcome</span>
<p class="selected">Welcome to W3docs</p>
<div class="selected">And again welcome</div>
<p class="biggest">And One Last Time</p>
</div>
<script>
$(document).ready(function() {
$("div").children(".selected").addClass("green");
});
</script>
</body>
</html>