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<meta http-equiv="X-UA-Compatible" content="ie=edge"> <title>Document</title>
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<div class="pic"><img src="https://ss1.baidu.com/6ONXsjip0QIZ8tyhnq/it/u=1438475101,354016904&fm=58" alt=""></div>
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<style>
.pic { width: 120px;height: 120px;margin: 40px auto;border: 1px solid #ccc;text-align: center;padding: 5px; }
.pic:before { content: "";display: inline-block;height: 100%;vertical-align: middle;width: 0; }
.pic img { max-width: 120px; max-height: 120px;vertical-align: middle; }
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原文：http://www.cnblogs.com/MagicZhao123/p/7252692.html