html,body {
	height: 100%;
	margin: 0px;
	font-size: 12px;
}

.mydiv {
	background-color: #DCF4FE;
	border: 0px solid #f00;
	text-align: center;
	line-height: 25px;
	font-size: 12px;
	font-weight: bold;
	z-index: 99;
	width: 300px;
	height: 60px;
	left: 50%; /*FF IE7*/
	top: 50%; /*FF IE7*/
	margin-left: -150px !important; /*FF IE7 该值为本身宽的一半 */
	margin-top: -200px !important; /*FF IE7 该值为本身高的一半*/
	margin-top: 0px;
	position: fixed !important; /*FF IE7*/
	position: absolute; /*IE6*/
	_top: expression(eval(document .   compatMode &&  
    document .   compatMode ==   'CSS1Compat') ?  
    documentElement .   scrollTop +     (   document .   documentElement
		. 
		 clientHeight-this .   offsetHeight )/ 2 :   /*IE6*/  
    document .   body .   scrollTop +     (   document .   body .  
		clientHeight -   
		 this .   clientHeight )/ 2 ); /*IE5 IE5.5*/
}

.mydiv table{
	font-size: 12px;
	font-weight: bold;
	}

.bg {
	background-color: #666;
	width: 100%;
	height: 100%;
	left: 0;
	top: 0; /*FF IE7*/
	filter: alpha(opacity =   50); /*IE*/
	opacity: 0.5; /*FF*/
	z-index: 1;
	position: fixed !important; /*FF IE7*/
	position: absolute; /*IE6*/
	_top: expression(eval(document .   compatMode &&  
    document .   compatMode ==   'CSS1Compat') ?  
    documentElement .   scrollTop +     (   document .   documentElement
		. 
		 clientHeight-this .   offsetHeight )/ 2 :   /*IE6*/  
    document .   body .   scrollTop +     (   document .   body .  
		clientHeight -   
		 this .   clientHeight )/ 2 ); /*IE5 IE5.5*/
}