谁帮我把这个css改成能在ff实现
<%@LANGUAGE= "VBSCRIPT "   CODEPAGE= "936 "%>  
  <!DOCTYPE   html   PUBLIC    "-//W3C//DTD   XHTML   1.0   Transitional//EN "    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd ">  
  <html   xmlns= "http://www.w3.org/1999/xhtml ">  
  <head>  
  <meta   http-equiv= "Content-Type "   content= "text/html;   charset=gb2312 "   />  
  <title> 无标题文档 </title>  
  <style   type= "text/css ">  
 #lightbox   {/*该层为高亮显示层*/ 
 	/*display:   none;*/ 
 	width:352px; 
 	height:150px; 
 	position:absolute; 
 	font-size:14px; 
 	font-family: "Tahoma ",Verdana,Arial,宋体; 
 	z-index:9990; 
 	top:   190px; 
 	left:   33%; 
 } 
 .lightbox.main{ 
 	z-index:9999; 
 	position:absolute; 
 	top:0px; 
 	left:0px; 
 } 
    .lightbox.main.main_inner{ 
    	width:350px; 
 	height:148px; 
 	background:#fff   url(images/loading.gif)   15px   30px   no-repeat; 
 	border:1px   solid   #ccc; 
 	border-right:1px   solid   #666; 
 	border-bottom:1px   solid   #666; 
    } 
          .lightbox.main.main_inner.con{ 
                padding:20px   20px; 
 	   position:absolute; 
 	   left:50px; 
    } 
          .lightbox.main.main_inner.btn{ 
                text-align:center; 
 	   position:absolute; 
 	   top:100px; 
 	   width:100%; 
 	} 
 .lightbox.shadow{ 
 z-index:9998; 
 position:absolute; 
 top:4px; 
 left:4px; 
 width:352px; 
 height:150px; 
 background:#666; 
 opacity:0.2; 
 filter:alpha(opacity=20); 
 }   
  </style>  
  </head>    
  <body>    
  <div   id= "lightbox ">  
        <div   class= "main ">  
              <div   id= "main_inner "   class= "main_inner ">  
                    <div   id= "lb_con "   class= "con ">     </div>  
                    <div   class= "btn ">  
                          <input   id= "lb_btn "   type= "button ">  
                    </div>  
              </div>  
        </div>  
        <div   class= "shadow ">  </div>  
  </div>    
  </body>  
  </html>
------解决方案--------------------ie就能么? =_=   
 class= "main " // css就得用 .main 
 id= "lightbox " // css就得用 #lightbox   
 多选择符 
  <div id= "lightbox ">  
  <div class= "main ">  </div>  
  </div>  
 可以写成#lightbox .main 
 注意中间有空格的