收藏一个韩国棒子的未知高度居中方法

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<title>利用图片</title> 
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.itm img{vertical-align:middle;}
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<body class="itm"> 
<img src="blank.gif" class="blank" alt="xx"/> 
<a href="#"><img src="http://lite-ext.googlecode.com/svn/trunk/lite-ext/playground/vertical-center/m060616.jpg"alt="yy"/></a> 
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