PNG支持IE和FF透明的CSS写法

<style>

.pic{
filter:progid:DXImageTransform.Microsoft.AlphaImageLoader(enabled=bEnabled, sizingMethod=sSize, src='b24_b.png');
background-image:url(b24_b.png)!important; background:none;
}

</style>

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<td width="78" height="78" class="pic"></td>

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