JS + CSS 实现导航下拉菜单 

<html>
<head>
	<title>www.mimvp.com</title>
	<style>
		* { 
			padding:0; 
			margin:0; 
			color: white;
		} 
		.blog-nav-item {
		  position: relative;
		  display: inline-block;
		  padding: 10px;
		  font-weight: 500;
		  color: #cdddeb;
		}
		#nav-title {
			margin: 0 auto;
		}
		#navigation, #navigation li ul { 
			list-style-type:none; 
			line-height: 30px;
			width: 100%;
		} 
		#navigation li { 
			float:left; 
			text-align:center; 
			position:relative; 
			
		} 
		#navigation li a:link, #navigation li a:visited { 
			display:block; 
			text-decoration:none; 
			width:120px; 
			background:#375069; 
			padding-left:10px; 
		} 
		#navigation li a:hover { 
			color:#fff; 
			background:#2687eb; 
		} 
		#navigation li ul li a:hover { 
			color:#fff; 
			background:#6b839c; 
		} 
		#navigation li ul { 
			display:none; 
			position:absolute; 
			top:40px; 
			left:0; 
			margin-top:1px; 
			width:120px; 
		} 
		#navigation li ul li ul { 
			display:none; 
			position:absolute; 
			top:0px; 
			left:130px; 
			margin-top:0; 
			margin-left:1px; 
			width:120px; 
		} 
	</style>
	
	<script type="text/javascript"> 
		function displaySubMenu(li) { 
			var subMenu = li.getElementsByTagName("ul")[0]; 
			subMenu.style.display = "block"; 
		} 

		function hideSubMenu(li) { 
			var subMenu = li.getElementsByTagName("ul")[0]; 
			subMenu.style.display = "none"; 
		} 
	</script> 
</head>

<body>
	<div class="nav-title">
		<ul id="navigation"> 
			<li onmouseover="displaySubMenu(this)" onmouseout="hideSubMenu(this)"> 
				<a class="blog-nav-item" href="http://proxy.mimvp.com/index.php">首页</a> 
			</li>
			<li onmouseover="displaySubMenu(this)" onmouseout="hideSubMenu(this)"> 
				<a class="blog-nav-item" href="http://proxy.mimvp.com/free.php">免费代理</a> 
			</li>
			<li onmouseover="displaySubMenu(this)" onmouseout="hideSubMenu(this)"> 
				<a class="blog-nav-item" href="http://proxy.mimvp.com/price.php">购买代理</a> 
			</li>
			<li onmouseover="displaySubMenu(this)" onmouseout="hideSubMenu(this)"> 
				<a class="blog-nav-item" href="http://proxy.mimvp.com/fetch.php">提取代理</a> 
			</li>
			
			<li onmouseover="displaySubMenu(this)" onmouseout="hideSubMenu(this)"> 
				<a class="blog-nav-item active" href="http://proxy.mimvp.com/stat.php">统计代理</a> 
				<ul> 
					<a class="blog-nav-item" href="http://proxy.mimvp.com/check.php">检测代理</a> 
					<a class="blog-nav-item" href="http://proxy.mimvp.com/apidoc.php">API 接口</a> 
					<a class="blog-nav-item" href="http://proxy.mimvp.com/help.php">帮助文档</a> 
				</ul> 
			</li> 
			
			<li onmouseover="displaySubMenu(this)" onmouseout="hideSubMenu(this)"> 
				<a class="blog-nav-item" href="http://proxy.mimvp.com/usercenter/userinfo.php">会员中心</a> 
				<ul> 
					<a class="blog-nav-item" href="http://proxy.mimvp.com/usercenter/login.php">用户登陆</a>
					<a class="blog-nav-item" href="http://proxy.mimvp.com/usercenter/regist.php">用户注册</a>  
				</ul> 
			</li> 

			<li onmouseover="displaySubMenu(this)" onmouseout="hideSubMenu(this)"> 
				<a class="blog-nav-item" href="http://proxy.mimvp.com/about.php">关于我们</a> 
				<ul> 
					<a class="blog-nav-item" href="http://proxy.mimvp.com/private.php">隐私保护</a> 
					<a class="blog-nav-item" target="_blank" href="https://blog.mimvp.com/">米扑博客</a> 
					<a class="blog-nav-item" target="_blank" href="http://forum.mimvp.com/">米扑论坛</a> 
				</ul> 
			</li> 
		</ul> 
	</div> 
</body>	
</html>

运行效果：

page-navigation-menu-dropdown-style

 

网站实际效果

米扑代理： http://proxy.mimvp.com