【vertical_align】
<!DOCTYPE html>
<html>
<head>
<style type='text/css'>
#main {
outline: 1px solid blue;
height: auto;
line-height: 400px;
text-align: center;
}
#main .top {
vertical-align: top;
}
#main .mid {
vertical-align: middle;
}
#main .bot {
vertical-align: bottom;
}
</style>
</head>
<body>
<div id="main">
<img class="mid"
src="http://eska-fuses.cn/style/download.png"
width="100" height="100" />
</div>
</body>
</html>
