代码示例：（标识：css3_transition_speed）
<!DOCTYPE html>
<html>
<head>
<style>
div {
width: 100px;
height: 100px;
background: red;
transition: width 2s;
}
#div1 {transition-timing-function: linear;}
#div2 {transition-timing-function: ease;}
#div3 {transition-timing-function: ease-in;}
#div4 {transition-timing-function: ease-out;}
#div5 {transition-timing-function: ease-in-out;}
div:hover {
width: 300px;
}
</style>
</head>
<body>
<h1>transition-timing-function 属性</h1>
<p>请把鼠标悬停在下面的 div 元素上，来查看不同的速度曲线：</p>
<div id="div1">linear</div><br>
<div id="div2">ease</div><br>
<div id="div3">ease-in</div><br>
<div id="div4">ease-out</div><br>
<div id="div5">ease-in-out</div><br>
<p><b>注释：</b>本例在 Internet Explorer 9 和更早版本中不起作用。</p>
</body>
</html>
