Problems in creating horizontal drop-down menus using div+css

According to your structure, considering that ie6 does not support the li:hover pseudo-class writing method, I solved it with jQuery.

*{margin:0;padding:0;font-size:14px;line-height:35px;}

a{color:#0099cc;text-decoration:none;}

ul,li{list-style:none;}

#menu{width:800px ;height:35px;background:#333333;}

#menu?ul?li{float:left;width:100px;margin-left:1px;position:relative;}

#menu?ul?li?ul?li{margin-left:0;}

#menu?ul?li?a{width:100%;height:100%;text-align:center ;display:block;background:#666666;}

/*Second-level column*/

#menu?ul?li?ul{display:none;position:absolute;left :0;top:35px;}

#menu?ul?li?ul?a{background:#333333;}

First-level column 3
- Second-level column 1
- Second-level column 2
- Two Level Column 3
?

First-level column 4
- Second-level column 4
- Secondary column 5
- Secondary column 6
?

$(function(){

$("#menu?ul?>?li").hover(function(){

$ (this).find("ul").stop(true,true).show(100);

},function(){

$(this).find( "ul").stop(true,true).hide(100);

})