【发布时间】：2019-08-01 01:38:09
【问题描述】：
我是 Boostrap 的新手，我试图让导航栏对所有屏幕都更具响应性，并在导航栏失去背景颜色的过程中添加一些效果。 我已经尝试明确采用 navbar-light 类并更改了它的颜色，但它似乎不起作用。
HTML：
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<meta http-equiv="X-UA-Compatible" content="IE=edge" />
<title>
Navbar
</title>
<meta name="viewport" content="width=device-width, initial-scale=1" />
<link
rel="stylesheet"
href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css"
integrity="sha384-Gn5384xqQ1aoWXA+058RXPxPg6fy4IWvTNh0E263XmFcJlSAwiGgFAW/dAiS6JXm"
crossorigin="anonymous"
/>
<link rel="stylesheet" type="text/css" media="screen" href="main.css" />
<script src="main.js"></script>
</head>
<body>
<header class="header_area">
<div class="main_menu">
<nav class="navbar navbar-expand-lg navbar-light">
<div class="container box_1620">
<a class="navbar-brand logo_h" href="index.html"><h2>Brand</h2></a>
<button
class="navbar-toggler"
type="button"
data-toggle="collapse"
data-target="#navbarSupportedContent"
aria-controls="navbarSupportedContent"
aria-expanded="false"
aria-label="Toggle navigation"
>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
</button>
<div
class="collapse navbar-collapse offset"
id="navbarSupportedContent"
>
<ul class="nav navbar-nav menu_nav ml-auto">
<li class="nav-item active">
<a class="nav-link" href="index.html">Home</a>
</li>
<li class="nav-item">
<a class="nav-link" href="about.html">About Us</a>
</li>
<li class="nav-item">
<a class="nav-link" href="pricing.html">Pricing</a>
</li>
<li class="nav-item">
<a class="nav-link" href="gallery.html">Gallery</a>
</li>
<li class="nav-item">
<a class="nav-link" href="contact.html">Contact</a>
</li>
</ul>
</div>
</div>
</nav>
</div>
</header>
<script
src="https://code.jquery.com/jquery-3.2.1.slim.min.js"
integrity="sha384-KJ3o2DKtIkvYIK3UENzmM7KCkRr/rE9/Qpg6aAZGJwFDMVNA/GpGFF93hXpG5KkN"
crossorigin="anonymous"
></script>
<script
src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.9/umd/popper.min.js"
integrity="sha384-ApNbgh9B+Y1QKtv3Rn7W3mgPxhU9K/ScQsAP7hUibX39j7fakFPskvXusvfa0b4Q"
crossorigin="anonymous"
></script>
<script
src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/js/bootstrap.min.js"
integrity="sha384-JZR6Spejh4U02d8jOt6vLEHfe/JQGiRRSQQxSfFWpi1MquVdAyjUar5+76PVCmYl"
crossorigin="anonymous"
></script>
</body>
</html>
CSS：
.header_area {
padding: 0px;
border: 0px;
border-width: 0px;
position: absolute;
width: 100%;
top: 0;
left: 0;
z-index: 99;
-webkit-transition: background 0.4s, all 0.3s linear;
-o-transition: background 0.4s, all 0.3s linear;
transition: background 0.4s, all 0.3s linear;
}
.header_area .navbar {
padding: 0px;
border: 0px;
border-width: 0px;
}
.header_area .navbar .nav .nav-item {
margin-right: 45px;
}
.header_area .navbar .nav .nav-item .nav-link {
font: 500 12px/100px "Roboto", sans-serif;
text-transform: uppercase;
color: #222222;
padding: 0px;
display: inline-block;
}
.header_area .navbar .nav .nav-item .nav-link:after {
display: none;
}
.header_area .navbar .nav .nav-item:hover .nav-link,
.header_area .navbar .nav .nav-item.active .nav-link {
color: #ff2f92;
}
.header_area .navbar .nav .nav-item.submenu {
position: relative;
}
.header_area .navbar .nav .nav-item.submenu ul {
border: none;
padding: 0px;
border-radius: 0px;
-webkit-box-shadow: none;
box-shadow: none;
margin: 0px;
background: #fff;
}
@media (min-width: 992px) {
.header_area .navbar .nav .nav-item.submenu ul {
position: absolute;
top: 120%;
left: 0px;
min-width: 200px;
text-align: left;
opacity: 0;
-webkit-transition: all 300ms ease-in;
-o-transition: all 300ms ease-in;
transition: all 300ms ease-in;
display: block;
border: none;
padding: 0px;
border-radius: 0px;
}
}
.header_area .navbar .nav .nav-item.submenu ul:before {
content: "";
width: 0;
height: 0;
border-style: solid;
border-color: #eeeeee transparent transparent transparent;
position: absolute;
right: 24px;
top: 45px;
z-index: 3;
opacity: 0;
-webkit-transition: all 400ms linear;
-o-transition: all 400ms linear;
transition: all 400ms linear;
}
.header_area .navbar .nav .nav-item.submenu ul .nav-item {
display: block;
float: none;
margin-right: 0px;
border-bottom: 1px solid #ededed;
margin-left: 0px;
-webkit-transition: all 0.4s linear;
-o-transition: all 0.4s linear;
transition: all 0.4s linear;
}
.header_area .navbar .nav .nav-item.submenu ul .nav-item .nav-link {
line-height: 45px;
color: #222222;
padding: 0px 30px;
-webkit-transition: all 150ms linear;
-o-transition: all 150ms linear;
transition: all 150ms linear;
display: block;
margin-right: 0px;
}
.header_area .navbar .nav .nav-item.submenu ul .nav-item:last-child {
border-bottom: none;
}
.header_area .navbar .nav .nav-item.submenu ul .nav-item:hover .nav-link {
background: #ff2f92;
color: #fff;
}
@media (min-width: 992px) {
.header_area .navbar .nav .nav-item.submenu:hover ul {
visibility: visible;
opacity: 1;
top: 100%;
}
}
.header_area .navbar .nav .nav-item.submenu:hover ul .nav-item {
margin-top: 0px;
}
.header_area .navbar .nav .nav-item:last-child {
margin-right: 0px;
}
.header_area + section,
.header_area + row,
.header_area + div {
margin-top: 100px;
}
.header_area.navbar_fixed .main_menu {
position: fixed;
width: 100%;
top: -70px;
left: 0;
right: 0;
background: #fff;
-webkit-transform: translateY(70px);
-ms-transform: translateY(70px);
transform: translateY(70px);
-webkit-transition: background 500ms ease, -webkit-transform 500ms ease;
transition: background 500ms ease, -webkit-transform 500ms ease;
-o-transition: transform 500ms ease, background 500ms ease;
transition: transform 500ms ease, background 500ms ease;
transition: transform 500ms ease, background 500ms ease,
-webkit-transform 500ms ease;
-webkit-transition: transform 500ms ease, background 500ms ease;
-webkit-box-shadow: 0px 3px 16px 0px rgba(0, 0, 0, 0.1);
box-shadow: 0px 3px 16px 0px rgba(0, 0, 0, 0.1);
}
我想知道为什么会发生这种情况，我出错的地方以及我的问题的解决方案。
【问题讨论】：
标签： html css bootstrap-4 navbar