<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title></title>
<script>
window.onload = function(){
var oBnt1 = document.getElementById('bnt1');
var oBnt2 = document.getElementById('bnt2');
var oP = document.getElementById('text');
var num = 16;
oBnt1.onclick = function(){
num –;
oP.style.fontSize = num+'px';
}
oBnt2.onclick = function(){
num ++;
oP.style.fontSize = num+'px';
}
}
</script>
</head>
<body>
<input id="bnt1" type="button" value="-" />
<input id="bnt2" type="button" value="+" />
<p id="text">萝卜白菜<br>红萝卜，大白菜，红的红来白的白。吃萝卜，吃白菜，圆圆的脸儿真可爱。</p>
</body>
