用css检测浏览器是否

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.ie6 .txt { float:left; padding-left:10px; }
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<span class="txt">廊坊网提示：您的浏览器可能是ie6或以下版本，为了您获得更好的上网体验，建议立即升级浏览器。<a href="http://www.google.cn/chrome" target="_blank" title="最好用的浏览器">猛击这里安装谷歌chrome浏览器</a></span>
<span class="close" οnclick="#" title="真的要关闭吗？">关闭</span>
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