问Borders封装的引导4 Navbar菜单

EN

.nav-item {
 border-right: 1px solid silver;
 padding-right: 15px; 
}   
.nav-item:first-child {
  border-left: 1px solid silver;
  padding-left: 15px;
}  

<link href="https://cdn.rawgit.com/twbs/bootstrap/v4-dev/dist/css/bootstrap.css" rel="stylesheet"/>

<nav class="navbar navbar-light" style="background-color:#fff">
  <ul class="nav navbar-nav">
    <li class="nav-item active">
      <a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
    </li>
    <li class="nav-item">
      <a class="nav-link" href="#">Features</a>
    </li>
    <li class="nav-item">
      <a class="nav-link" href="#">Pricing</a>
    </li>
    <li class="nav-item">
      <a class="nav-link" href="#">About</a>
    </li>
  </ul>
</nav>