<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
"http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<title>css样式</title>
<style>
.bigger{
font-size: 30px;
}
.small{
font-size: 15px;
}
</style>
</head>
<body>
<div id="div1">star is superb</div>
<input type="submit" onclick="change('bigger')" value="big">
<input type="submit" onclick="change('small')" value="small">
<script>
//引入美化部门已经设计好的css样式
// var ele=document.getElementsByClassName('ele');
// $('.ele')//引入美化部门已经设计好的css样式
function change(self) {
var ele=document.getElementById('div1');
ele.classList.add(self);
}
</script>
</body>
</html>