我正在将一个网站从Bootstrap 3升级到4(beta)。我之前使用的用于给活动导航链接加下划线的CSS不再起作用了。它不是给选项添加下划线,而是给整个页面添加下划线。你如何在Bootstrap 4中给活动的导航项下划线呢?
Bootstrap 3 CSS:
.navbar-default .navbar-nav > .active:after {
position: absolute;
bottom: 0;
left: 0;
width: 100%;
content: " ";
border-bottom: 5px solid #5BC0EB;
}
尝试使用 Bootstrap 4 的 CSS
.navbar-light .navbar-nav .active::after {
position: absolute;
bottom: 0;
left: 0;
width: 100%;
content: " ";
border-bottom: 5px solid #5BC0EB;
}
HTML
<nav class="navbar fixed-top navbar-light bg-light navbar-expand-md">
<div class="container">
<a class="navbar-brand" href="#">My Website</a>
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarCollapse" aria-controls="navbarCollapse"
aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse justify-content-end" id="main-nav-collapse">
<ul class="navbar-nav">
<li class="nav-item active"><a class="nav-link" href="#about">About</a></li>
<li class="nav-item"><a class="nav-link" href="#classes">Classes</a></li>
<li class="nav-item"><a class="nav-link" href="#gallery">Gallery</a></li>
<li class="nav-item"><a class="nav-link" href="#events">Events</a></li>
<li class="nav-item"><a class="nav-link" href="#contact">Contact</a></li>
<li class="nav-item"><a class="nav-link" href="#offers">Offers</a></li>
</ul>
</div>
</div>
</nav>