css樣式：
/* CSS Document */
*{
padding:0;
margin:0;
}
body{
font-size:12px;
font-family:"宋體";
line-height:1.5;
}
ul{
list-style:none;
}
a{
text-decoration:none;
}
.clear{
clear:both;
}
#menu{
width:900px;
height:30px;
margin:50px auto;
}
#menu ul li{
float:left;
position:relative;
}
#menu ul li a{
width:120px;
height:30px;
line-height:30px;
display:block;
text-align:center;
font-size:14px;
background:#F90;
border:1px solid #000;
color:#000;
}
#menu ul li ul{display:none;}
#menu ul li:hover a{
color:#f00;
background:#FFF;
}
#menu ul li:hover ul {
display:block;
position:absolute;
top:30px;
left:0;
width:120px;
}
#menu ul li:hover a {
display:block;
background:#faeec7;
color:#000;
}
#menu ul li:hover ul li a:hover {
background:#dfc184;
color:#000;
}
HTML程式碼：