#prvbackground{position:absolute;z-index:1000;left:0px;top:0px;width:100%;height:100%;background:gray;filter:alpha(opacity=50);-moz-opacity:.50;opacity:.50;}
#prvdiv{z-index:1003;position:absolute;top:150px;width:500;background:white;padding:5px 5px 5px 5px;border:solid 3px steelblue;margin:auto;}
#prvwrapper{position:absolute;z-index:1002;left:0px;top:0px;width:500px;text-align:center;}
.prvhide{display:none;}
.prvshow{display:inline;}