<!DOCTYPE html>
<html lang="zh-CN">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>页面练习</title>
<style>
*{margin:0;padding:0;}
img{display:block;}
ul li{list-style:none;}
a{text-decoration:none;color:#333333;}
a:hover{color:#84D4FF;text-decoration:underline;}
h1,h2,h3,h4,h5,h6{font-size: 14px;font-family:微软雅黑;font-weight:normal;}
#main{width:278px;border:1px #dbe2ea solid;margin:200px;}
#title1{height:36px;border-bottom:1px #dbe2ea solid;line-height: 36px;margin:0 auto;}
</style>
</head>
<body>
<div id="main">
<h1 id="title1">
<a href="#">移动标题</a>
</h1>
</div>
</body>
</html>
明明我在#title中设置了margin：0 auto；左右自适应了，但移动标题却不能居中显示？
