我遇到了问题。我刚刚从htmldrive.net下载了这段代码。我正在将它用于我的学校项目，我想在科学这个词悬停时添加另一个子菜单。谢谢。
HTML / PHP
<ul id="nav">
<li><a href="home.php">Home</a></li>
<li><a class="hsubs" href="questions.php">Questions</a>
<ul class="subs">
<li><a href="">Science</a></li>
<ul class="subss">
<li><a href="">Science</a></li>
</ul>
<li><a href="">English</a></li>
<li><a href="">Math</a></li>
</ul>
</li>
<li><a class="hsubs" href="facilities1.php">Facilities</a>
<ul class="subs">
<li><a href="#">Submenu 2-1</a></li>
<li><a href="#">Submenu 2-2</a></li>
<li><a href="#">Submenu 2-3</a></li>
<li><a href="#">Submenu 2-4</a></li>
<li><a href="#">Submenu 2-5</a></li>
<li><a href="#">Submenu 2-6</a></li>
<li><a href="#">Submenu 2-7</a></li>
<li><a href="#">Submenu 2-8</a></li>
</ul>
</li>
<li><a class="hsubs" href="#">Events</a>
<ul class="subs">
<li><a href="#">Submenu 3-1</a></li>
<li><a href="#">Submenu 3-2</a></li>
<li><a href="#">Submenu 3-3</a></li>
<li><a href="#">Submenu 3-4</a></li>
<li><a href="#">Submenu 3-5</a></li>
</ul>
</li>
<li><a href="#">About Us</a></li>
<li><a href="#">
<?php
$member=$_SESSION['member'];
$result=mysql_query("select * from account where member='$member'")or die(mysql_error);
$row=mysql_fetch_array($result);
$FirstName=$row['name'];
$Age=$row['surname'];
echo " Welcome ".$FirstName;
?>
</a></li>
<li><a href="logout.php?id=$member \">Logout</a></li>
<div id="lavalamp"></div>
</ul>
CSS
#nav,#nav ul {
list-style: none outside none;
margin: 0px 0px 0px 0px;
padding: 0;
}
#nav {
background: url('aa.jpg') no-repeat scroll 0 0 transparent;
clear: both;
font-size: 12px;
height: 58px;
padding: 0 0 0 9px;
position: relative;
width: 1200px;
}
#nav ul {
background-color: #222;
border:1px solid #222;
border-radius: 0 5px 5px 5px;
border-width: 0 1px 1px;
box-shadow: 0 5px 5px rgba(0, 0, 0, 0.5);
left: -9999px;
overflow: hidden;
position: absolute;
top: -9999px;
z-index: 2;
-moz-transform: scaleY(0);
-ms-transform: scaleY(0);
-o-transform: scaleY(0);
-webkit-transform: scaleY(0);
transform: scaleY(0);
-moz-transform-origin: 0 0;
-ms-transform-origin: 0 0;
-o-transform-origin: 0 0;
-webkit-transform-origin: 0 0;
transform-origin: 0 0;
-moz-transition: -moz-transform 0.1s linear;
-ms-transition: -ms-transform 0.1s linear;
-o-transition: -o-transform 0.1s linear;
-webkit-transition: -webkit-transform 0.1s linear;
transition: transform 0.1s linear;
}
#nav li {
background: url('menu_line.png') no-repeat scroll right 5px transparent;
float: left;
position: relative;
}
#nav li a {
color: #FFFFFF;
display: block;
float: left;
font-weight: normal;
height: 30px;
padding: 23px 20px 0;
position: relative;
text-decoration: none;
text-shadow: 1px 1px 1px #000000;
}
#nav li:hover > a {
color: #00B4FF;
}
#nav li:hover, #nav a:focus, #nav a:hover, #nav a:active {
background: none repeat scroll 0 0 #121212;
outline: 0 none;
}
#nav li:hover ul.subs {
left: 0;
top: 53px;
width: 180px;
-moz-transform: scaleY(1);
-ms-transform: scaleY(1);
-o-transform: scaleY(1);
-webkit-transform: scaleY(1);
transform: scaleY(1);
}
#nav ul li {
background: none;
width: 100%;
}
#nav ul li a {
float: none;
}
#nav ul li:hover > a {
background-color: #121212;
color: #00B4FF;
}
#lavalamp {
background: url('lavalamp.png') no-repeat scroll 0 0 transparent;
height: 16px;
left: 13px;
position: absolute;
top: 0px;
width: 64px;
-moz-transition: all 300ms ease;
-ms-transition: all 300ms ease;
-o-transition: all 300ms ease;
-webkit-transition: all 300ms ease;
transition: all 300ms ease;
}
#lavalamp:hover {
-moz-transition-duration: 3000s;
-ms-transition-duration: 3000s;
-o-transition-duration: 3000s;
-webkit-transition-duration: 3000s;
transition-duration: 3000s;
}
#nav li:nth-child(1):hover ~ #lavalamp {
left: 13px;
}
#nav li:nth-child(2):hover ~ #lavalamp {
left: 88px;
}
#nav li:nth-child(3):hover ~ #lavalamp {
left: 170px;
}
#nav li:nth-child(4):hover ~ #lavalamp {
left: 250px;
}
#nav li:nth-child(5):hover ~ #lavalamp {
left: 335px;
}
#nav li:nth-child(6):hover ~ #lavalamp {
left: 445px;
}
#nav li:nth-child(7):hover ~ #lavalamp {
left: 550px;
}
#nav li:nth-child(8):hover ~ #lavalamp {`enter code here`
left: 565px;
}
答案 0 :(得分：0)
我这是FIDDLE你在寻找什么？
我已经缩短了你的HTML - 你可以按照相同的模式扩展它。
HTML
<nav>
<ul>
<li><a href="#">Home</a></li>
<li><a href='#'>Questions</a>
<ul>
<li><a href="#">Science</a>
<ul>
<li><a href="">Physics</a></li>
<li><a href="">Chemistry</a></li>
<li><a href="">Physiology</a></li>
</ul>
</li>
<li><a href="">English</a></li>
<li><a href="">Math</a></li>
</ul>
</li>
<li><a href="#">Facilities</a>
<ul>
<li><a href="#">Submenu 2-1</a></li>
</ul>
</li>
</ul>
<nav>
CSS是小提琴，所以我不必在这里发帖 - 很长。
一个教学点是你真的可以使用纯CSS做大多数下拉菜单 - 不需要课程，ID等。