我有一个菜单在桌面视图上完美运行，当鼠标悬停时，将覆盖.gif图像。当设备宽度低于 768px 时，菜单响应正在工作，但图像叠加出现问题，其中显示所有图像而不是菜单的默认视图。
请参阅此链接以查看设计 http://testing.x-renaissance.com/
网页设计正在使用HTML + Bootstrap
.CSS
.overlay {
position: absolute;
bottom: 100%;
left: 0;
right: 0;
background-color: #000;
overflow: hidden;
width: 100%;
height: 100%;
transition: .5s ease;
text-align: center;
}
.overlay img { height: 50px; }
.nav-menu li:hover .overlay { bottom: 0; height: 100%; }
.HTML
<div class="navbar navbar-inverse navbar-fixed-top">
<div class="container">
<div class="navbar-header">
<button button type="button" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#navbar" aria-expanded="false" aria-controls="navbar">
<span class="sr-only">Toggle navigation</span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
</button>
<a class="navbar-brand" rel="Menu1" href="#" title="">
LOGO
</a>
</div>
<div id="navbar" class="collapse navbar-collapse navbar-responsive-collapse">
<ul class="nav navbar-nav nav-menu">
<li class="">
<a href="#" class="" title="Menu1">
<div class="overlay">
<img src="http://pa1.narvii.com/6050/e0e8fcb7950ad0fd900775fdde8e538ee00b88f8_hq.gif">
</div>
Menu1
</a>
</li>
<li>
<a href="#" class="h" title="Menu2">
<div class="overlay">
<img src="http://pa1.narvii.com/6050/e0e8fcb7950ad0fd900775fdde8e538ee00b88f8_hq.gif">
</div>
Menu2
</a>
</li>
<li class="dropdown">
<a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="false" title="Menu3">
<div class="overlay">
<img src="http://pa1.narvii.com/6050/e0e8fcb7950ad0fd900775fdde8e538ee00b88f8_hq.gif">
</div>
Menu3
</a>
</li>
<li>
<a href="#" class="" title="Menu4">
<div class="overlay">
<img src="http://pa1.narvii.com/6050/e0e8fcb7950ad0fd900775fdde8e538ee00b88f8_hq.gif">
</div>
Menu4
</a>
</li>
<li>
<a href="#" class="" title="Menu5">
<div class="overlay">
<img src="http://pa1.narvii.com/6050/e0e8fcb7950ad0fd900775fdde8e538ee00b88f8_hq.gif">
</div>
Menu5
</a>
</li>
<li>
<a href="#" class="" title="Menu6">
<div class="overlay">
<img src="http://pa1.narvii.com/6050/e0e8fcb7950ad0fd900775fdde8e538ee00b88f8_hq.gif">
</div>
Menu6
</a>
</li>
</ul>
</div>
</div>
</div>
这是因为您依赖于基于高度的隐藏，但是当它变成折叠菜单时，它不再具有该选项。我创建了一个媒体查询，该查询将根据折叠时的位置隐藏它。https://codepen.io/anon/pen/KqYgLX?editors=1010
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=0">
<title>Testing</title>
<link href="./assets/default/css/header-slider.css" rel="stylesheet"/>
<link href="./assets/default/css/custom.css" rel="stylesheet"/>
<link href="./assets/plugin/Hover-master/css/hover.css" rel="stylesheet" media="all">
<link href="./assets/plugin/font-awesome-4.7.0/css/font-awesome.min.css" rel="stylesheet" media="all">
<!-- bootstrap link -->
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap-theme.min.css" integrity="sha384-rHyoN1iRsVXV4nD0JutlnGaslCJuC7uwjduW9SVrLvRYooPp2bWYgmgJQIXwl/Sp" crossorigin="anonymous">
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous">
<script src="https://code.jquery.com/jquery-3.1.1.slim.min.js" integrity="sha384-A7FZj7v+d/sdmMqp/nOQwliLvUsJfDHW+k9Omg/a/EheAdgtzNs3hpfag6Ed950n" crossorigin="anonymous"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/tether/1.4.0/js/tether.min.js" integrity="sha384-DztdAPBWPRXSA/3eYEEUWrWCy7G5KFbe8fFjk5JAIxUYHKkDx6Qin1DkWx51bBrb" crossorigin="anonymous"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-alpha.6/js/bootstrap.min.js" integrity="sha384-vBWWzlZJ8ea9aCX4pEW3rVHjgjt7zpkNpZk+02D9phzyeVkE+jo0ieGizqPLForn" crossorigin="anonymous"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js" integrity="sha384-Tc5IQib027qvyjSMfHjOMaLkfuWVxZxUPnCJA7l2mCWNIpG9mGCD8wGNIcPD7Txa" crossorigin="anonymous"></script>
<!-- end of bootstrap link -->
</head>
<body><style type="text/css">
.overlay {
position: absolute;
bottom: 100%;
left: 0;
right: 0;
background-color: #000;
overflow: hidden;
width: 100%;
height: 100%;
transition: .5s ease;
text-align: center;
}
.overlay img { height: 50px; }
.nav-menu li:hover .overlay { bottom: 0; height: 100%; }
.navbar-inverse .navbar-nav>.active>a>.overlay { bottom: 0; height: 100%; }
@media screen and (max-width: 768px) {
.overlay {
bottom: 0 !important;
left: 100% !important;
background-color: red !important;
}
.nav-menu li:hover .overlay { left: 0 !important; height: 100%; }
}
</style>
<div class="navbar navbar-inverse navbar-fixed-top">
<div class="container">
<div class="navbar-header">
<button button type="button" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#navbar" aria-expanded="false" aria-controls="navbar">
<span class="sr-only">Toggle navigation</span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
</button>
<a class="navbar-brand" rel="Menu1" href="#" title="">
LOGO
</a>
</div>
<div id="navbar" class="collapse navbar-collapse navbar-responsive-collapse">
<ul class="nav navbar-nav nav-menu">
<li class="">
<a href="#" class="" title="Menu1">
<div class="overlay">
<img src="http://pa1.narvii.com/6050/e0e8fcb7950ad0fd900775fdde8e538ee00b88f8_hq.gif">
</div>
Menu1
</a>
</li>
<li>
<a href="#" class="h" title="Menu2">
<div class="overlay">
<img src="http://pa1.narvii.com/6050/e0e8fcb7950ad0fd900775fdde8e538ee00b88f8_hq.gif">
</div>
Menu2
</a>
</li>
<li class="dropdown">
<a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="false" title="Menu3">
<div class="overlay">
<img src="http://pa1.narvii.com/6050/e0e8fcb7950ad0fd900775fdde8e538ee00b88f8_hq.gif">
</div>
Menu3
</a>
</li>
<li>
<a href="#" class="" title="Menu4">
<div class="overlay">
<img src="http://pa1.narvii.com/6050/e0e8fcb7950ad0fd900775fdde8e538ee00b88f8_hq.gif">
</div>
Menu4
</a>
</li>
<li>
<a href="#" class="" title="Menu5">
<div class="overlay">
<img src="http://pa1.narvii.com/6050/e0e8fcb7950ad0fd900775fdde8e538ee00b88f8_hq.gif">
</div>
Menu5
</a>
</li>
<li>
<a href="#" class="" title="Menu6">
<div class="overlay">
<img src="http://pa1.narvii.com/6050/e0e8fcb7950ad0fd900775fdde8e538ee00b88f8_hq.gif">
</div>
Menu6
</a>
</li>
</ul>
</div>
</div>
</div>