JavaScript DHTML/Node Operation/addRule
"addRule()" Example
<html>
<head>
<style id="myS">.one { font-family:verdana; font-size:14pt }</style>
<script language="JavaScript">
function function1() {
document.styleSheets[0].addRule("div", "color:white; background-color:red;");
}
</script>
</head>
<body>
<div>This is a sample text.</div>
<button onclick="function1()">Add new rule</button>
</body>
</html>