【技术】ie兼容半透明

<div class="sexy_dance_img">
<ul>
<li class="fl sd1">
<a href="http://v.wudao.com/20140522/82054.html" target="_blank">
<img src="images/sexy_dance1.jpg" width="236" height="189" />
<div class="play_icon2"></div>
<span>一分一秒</span>
</a>
</li>

</ul>

</div>

.sexy_dance_img{ height:317px; width:1000px;}
.sexy_dance_img li.sd1{margin-right: 18px;}
.sexy_dance_img li{ width: 236px; height:189px; position:relative; margin-bottom:18px;}
.sexy_dance_img span{ display:none; position:absolute; left:0; bottom:0;}
.sexy_dance_img li a:hover span{ display:block; text-align:center; width:100%; line-height:30px; font-size:14px; color:#FFF; background-color:#000; filter:alpha(opacity=70);opacity:0.7; white-space:nowrap;-ms-text-overflow:ellipsis; text-overflow:ellipsis; overflow:hidden;}
.sexy_dance_img div.play_icon2{position:absolute;background: url("http://s001.wudaotv.com/t1/css/zt/zghwd/image/play-btn.png") no-repeat scroll 0% 0% transparent; background-size: 70%; width: 82px;height: 80px;left: 50%;margin-left: -28px;top: 50%;margin-top: -28px;}