IE9+及其他浏览器实现背景图片平铺可能需要一个属性就可以background-size:100%/cover;
但是ie8下background-size是不兼容的，因此我们需要用到滤镜，来解决背景图片拉伸问题。
仅需如下代码：
filter: progid:DXImageTransform.Microsoft.AlphaImageLoader(
src='../img/news/news-banner.png',
sizingMethod='scale');
-ms-filter: progid:DXImageTransform.Microsoft.AlphaImageLoader(
src='../img/news/news-banner.png',
sizingMethod='scale');
eg:
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width,initial-scale=1,user-scalable=no">
<meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1" />
<meta name="renderer" content="webkit" />
<title>投影仪－新闻中心</title>
<style type="text/css">
*{margin: 0;padding: 0;}
.news-banner{
width:100%;
height:225px;
background-position:50%;
background-size:cover;
background-repeat: no-repeat;
background-image:url(news-banner.png);
filter: progid:DXImageTransform.Microsoft.AlphaImageLoader(
src='news-banner.png',
sizingMethod='scale');
-ms-filter: progid:DXImageTransform.Microsoft.AlphaImageLoader(
src='news-banner.png',
sizingMethod='scale');
}
</style>
</head>
<body>
<div class="news-banner">
</div>
</body>
</html>