bootstrap 4 toggle bar
<nav class="navbar navbar-default">
<div class="container-fluid">
<!-- Brand and toggle get grouped for better mobile display -->
<div class="navbar-header">
<button type="button" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#bs-example-navbar-collapse-1" aria-expanded="false">
<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" href="#">Brand</a>
</div>
<!-- Collect the nav links, forms, and other content for toggling -->
<div class="collapse navbar-collapse" id="bs-example-navbar-collapse-1">
<ul class="nav navbar-nav">
<li class="active"><a href="#">Link <span class="sr-only">(current)</span></a></li>
<li><a href="#">Link</a></li>
<li class="dropdown">
<a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="false">Dropdown <span class="caret"></span></a>
<ul class="dropdown-menu">
<li><a href="#">Action</a></li>
<li><a href="#">Another action</a></li>
<li><a href="#">Something else here</a></li>
<li role="separator" class="divider"></li>
<li><a href="#">Separated link</a></li>
<li role="separator" class="divider"></li>
<li><a href="#">One more separated link</a></li>
</ul>
</li>
</ul>
<form class="navbar-form navbar-left">
<div class="form-group">
<input type="text" class="form-control" placeholder="Search">
</div>
<button type="submit" class="btn btn-default">Submit</button>
</form>
<ul class="nav navbar-nav navbar-right">
<li><a href="#">Link</a></li>
<li class="dropdown">
<a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="false">Dropdown <span class="caret"></span></a>
<ul class="dropdown-menu">
<li><a href="#">Action</a></li>
<li><a href="#">Another action</a></li>
<li><a href="#">Something else here</a></li>
<li role="separator" class="divider"></li>
<li><a href="#">Separated link</a></li>
</ul>
</li>
</ul>
</div><!-- /.navbar-collapse -->
</div><!-- /.container-fluid -->
</nav>
/* Toggle menu */
<nav class="navbar navbar-expand-md bg-dark
navbar-dark">
<!-- Brand -->
<a class="navbar-brand" href="#">Navbar</a>
<!-- Toggler/collapsibe Button -->
<button
class="navbar-toggler" type="button"
data-toggle="collapse" data-target="#collapsibleNavbar">
<span class="navbar-toggler-icon"></span>
</button>
<!-- Navbar links -->
<div class="collapse navbar-collapse"
id="collapsibleNavbar">
<ul class="navbar-nav">
<li class="nav-item">
<a class="nav-link"
href="#">Link</a>
</li>
<li class="nav-item">
<a class="nav-link"
href="#">Link</a>
</li>
<li class="nav-item">
<a class="nav-link"
href="#">Link</a>
</li>
</ul>
</div>
</nav>
<div class="pos-f-t">
<div class="collapse" id="navbarToggleExternalContent">
<div class="bg-dark p-4">
<h4 class="text-white">Collapsed content</h4>
<span class="text-muted">Toggleable via the navbar brand.</span>
</div>
</div>
<nav class="navbar navbar-dark bg-dark">
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarToggleExternalContent" aria-controls="navbarToggleExternalContent" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
</nav>
</div>