<!-- background-size-polyfill v0.2.0 | (c) 2012-2013 Louis-Rémi Babé | MIT License -->
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将以上 代码保存为 backgroundsize.min.htc
在background-size所在class中加入
-ms-behavior: url(css/backgroundsize.min.htc);
behavior: url(css/backgroundsize.min.htc);
参考 ：http://www.dowebok.com/139.html