<container style="position: absolute; top: 0px; left: 0px; width: 0px; height: 0px; z-index: 100;">
<div id="_dropBoxTemp_" style="display: none;"></div>
 <!--设置背景灰色-->
<div style="background: none repeat scroll 0% 0% rgb(0, 0, 0); position: absolute; left: 0px; top: 0px; width: 1264px; height: 1008px; opacity: 0.5;"></div>
 

<!--可以操作-->

<div    style="position: absolute; display: block; left: 165px; top: 138px;">
<a class="close" href="javascript:void(0);" >×</a>

 ...

</div>

</container>

主窗口

<div class="main">

...

</div>

html背景为灰色 不能操作,中间div可以操作