请参阅我的工作示例。 正如您所看到的，背景颜色并未覆盖整个事件元素。 当我删除过渡 CSS 时，它将像本示例一样工作(请将浏览器大小调整为移动版本)
https://getbootstrap.com/examples/navbar-fixed-top/#
如何解决这个问题？
/* Navbar */
.navbar-fixed-top{
top: 80px;
}
.navbar-default{ /* assigning the top bar to the entire navbar div element */
background-color: #4F4F4F;
}
nav.navbar {
box-shadow: 0 0 2px 0 #ccc;
}
nav.navbar a {
color: #FF7D36;
}
nav.navbar ul.navbar-nav a {
color: #FF7D36;
border-style: solid;
border-width: 0 0 2px 0;
border-color: #000;
}
nav.navbar ul.navbar-nav a:hover,
nav.navbar ul.navbar-nav a:visited,
nav.navbar ul.navbar-nav a:focus,
nav.navbar ul.navbar-nav a:active {
background: #000;
}
nav.navbar ul.navbar-nav a {
text-decoration: none;
position: relative;
display: inline-block;
}
nav.navbar ul.navbar-nav a::after {
content: '';
width: 80%;
position: absolute;
top: 100%;
left: 10%;
height: 2px;
background-color: #FF7D36;
transform: scaleX(0);
transition: transform .35s ease;
}
nav.navbar ul.navbar-nav a:hover::after {
transform: scaleX(1);
}<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>Basic Bootstrap Template</title>
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous">
<!-- Optional Bootstrap theme -->
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap-theme.min.css" integrity="sha384-rHyoN1iRsVXV4nD0JutlnGaslCJuC7uwjduW9SVrLvRYooPp2bWYgmgJQIXwl/Sp" crossorigin="anonymous">
</head>
<body>
<nav class="navbar navbar-inverse navbar-fixed-top">
<div class="container">
<div class="navbar-header">
<button type="button" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#navbar" aria-expanded="false" aria-controls="navbar">
<span class="sr-only">Navigation ein-/ausblenden</span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
</button>
<a class="navbar-brand" href="#">Projekt-Titel</a>
</div>
<div id="navbar" class="collapse navbar-collapse">
<ul class="nav navbar-nav">
<li class="active"><a href="#">Start</a></li>
<li><a href="#ueber">Über</a></li>
<li><a href="#kontakt">Kontakt</a></li>
</ul>
</div><!--/.nav-collapse -->
</div>
</nav>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.12.4/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js" integrity="sha384-Tc5IQib027qvyjSMfHjOMaLkfuWVxZxUPnCJA7l2mCWNIpG9mGCD8wGNIcPD7Txa" crossorigin="anonymous"></script>
</body>
</html> 最佳答案
我在你的代码片段中评论了一行:
nav.navbar ul.navbar-nav a {
text-decoration: none;
position: relative;
/* display: inline-block; */
}
使用该行，您覆盖了此 Bootstrap 规则:
.nav > li > a {
position: relative;
display: block;
padding: 10px 15px;
}
您遇到了 CSS specificity 的问题.
这里是更正的代码片段:
/* Navbar */
.navbar-fixed-top{
top: 80px;
}
.navbar-default{ /* assigning the top bar to the entire navbar div element */
background-color: #4F4F4F;
}
nav.navbar {
box-shadow: 0 0 2px 0 #ccc;
}
nav.navbar a {
color: #FF7D36;
}
nav.navbar ul.navbar-nav a {
color: #FF7D36;
border-style: solid;
border-width: 0 0 2px 0;
border-color: #000;
}
nav.navbar ul.navbar-nav a:hover,
nav.navbar ul.navbar-nav a:visited,
nav.navbar ul.navbar-nav a:focus,
nav.navbar ul.navbar-nav a:active {
background: #000;
}
nav.navbar ul.navbar-nav a {
text-decoration: none;
position: relative;
/* display: inline-block; */
}
nav.navbar ul.navbar-nav a::after {
content: '';
width: 80%;
position: absolute;
top: 100%;
left: 10%;
height: 2px;
background-color: #FF7D36;
transform: scaleX(0);
transition: transform .35s ease;
}
nav.navbar ul.navbar-nav a:hover::after {
transform: scaleX(1);
}<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>Basic Bootstrap Template</title>
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous">
<!-- Optional Bootstrap theme -->
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap-theme.min.css" integrity="sha384-rHyoN1iRsVXV4nD0JutlnGaslCJuC7uwjduW9SVrLvRYooPp2bWYgmgJQIXwl/Sp" crossorigin="anonymous">
</head>
<body>
<nav class="navbar navbar-inverse navbar-fixed-top">
<div class="container">
<div class="navbar-header">
<button type="button" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#navbar" aria-expanded="false" aria-controls="navbar">
<span class="sr-only">Navigation ein-/ausblenden</span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
</button>
<a class="navbar-brand" href="#">Projekt-Titel</a>
</div>
<div id="navbar" class="collapse navbar-collapse">
<ul class="nav navbar-nav">
<li class="active"><a href="#">Start</a></li>
<li><a href="#ueber">Über</a></li>
<li><a href="#kontakt">Kontakt</a></li>
</ul>
</div><!--/.nav-collapse -->
</div>
</nav>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.12.4/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js" integrity="sha384-Tc5IQib027qvyjSMfHjOMaLkfuWVxZxUPnCJA7l2mCWNIpG9mGCD8wGNIcPD7Txa" crossorigin="anonymous"></script>
</body>
</html> 关于html - 带有过渡边框的 Twitter Bootstrap 导航栏 - 背景颜色未覆盖整个事件元素，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/38719708/