Bootstrap Navbar collapse point < 768px - html

Question

This is an OLD question for Bootstrap 3 -> changing the collapse point for the navbar, but the methodologies suggested here:
https://coderwall.com/p/wpjw4w/change-the-bootstrap-navbar-breakpoint
and here:
Bootstrap 3 Navbar Collapse
do not work for collapsing below 768px, it only seems to work for extending the collapse point, not retracting it. I have a particular situation where my navbar has 3 buttons, so it doesn't need to collapse so early. I would like it to collapse at 420px instead.
Is there a CSS solution to this? If not, can somebody point me towards the correct attribute in the bootstrap customisation page which I need to change and download? Is it the generic breakpoints perhaps? Because there is nothing I can see which says Navbar breakpoints:
http://getbootstrap.com/customize/
As requested, my HTML for the navbar is simply:
<nav class="navbar navbar-default navbar-fixed-top">
<div class="container-fluid">
<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">Toggle navigation</span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
</button>
</div>
<div class="navbar-collapse collapse" id = "navbar">
<ul class="nav navbar-nav navbar-left">
<li class = "navbar_buttons"><a id = "new_route_button"><strong>New Route</strong></a></li>
<li class="divider-vertical"></li>
<li class = "navbar_buttons"><a id = "clear_route_button">Clear Route</a></li>
</ul>
<ul class="nav navbar-nav navbar-right"> <!--Right justified navbar list-->
<li class = "navbar_buttons"><a id = "about_button">About</a></li>
</ul>
</div>
</div> <!-- Container -->
</nav> <!-- End of Navbar Container -->
Then I have some CSS to add a vertical division:
/*Preventing vertical dividers from appearing collapsed*/
#media (max-width: 420px) {
.navbar-collapse .nav > .divider-vertical {
display: none;
}
}
/*Defining the vertical dividers*/
.navbar .divider-vertical {
height: 50px;
margin: 0 9px;
border-right: 1px solid #ffffff;
border-left: 1px solid #DADADA;
}
.navbar-inverse .divider-vertical {
border-right-color: #222222;
border-left-color: #111111;
}

Answer 1

Yes, changing the breakpoint to anything less than 768px is different than changing the breakpoint over 768px. You need to override all of the Bootstrap defaults that normally make it collapse.
#media only screen and (min-width: 420px) {
.collapse {
display: block;
}
.navbar-header {
float: left;
}
.navbar-toggle {
display: none;
}
.navbar-nav.navbar-left {
float: left;
margin: 0;
}
.navbar-nav.navbar-right {
float: right;
margin: 0;
}
.navbar-nav>li {
float: left;
}
.navbar-nav>li>a {
padding-top: 15px;
padding-bottom: 15px;
}
}
#media only screen and (max-width: 420px) {
.collapse {
display: none;
}
.navbar-header {
display: block;
}
}
http://www.bootply.com/wpUuFIZqJ2

Answer 2

The following code snippet is based on the original answer, but also works when there are drop down menus in the navbar.
<link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet" />
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
<style>
#media only screen and (min-width: 560px) {
.collapse {
display: block;
}
.navbar-header {
float: left;
}
.navbar-toggle {
display: none;
}
.navbar>.container .navbar-brand,
.navbar>.container-fluid .navbar-brand {
margin-left: -15px;
}
.container>.navbar-header,
.container-fluid>.navbar-header,
.container>.navbar-collapse,
.container-fluid>.navbar-collapse {
margin-right: 0;
margin-left: 0;
}
.navbar-nav {
float: left;
margin: 0;
}
.navbar-nav.navbar-right {
float: right;
margin: 0;
}
.navbar-nav>li {
float: left;
}
.navbar-nav>li>a {
padding-top: 15px;
padding-bottom: 15px;
}
.navbar-nav .open .dropdown-menu {
position: absolute;
float: left;
width: auto;
margin-top: 2px;
background-color: #fff;
border: 1px solid #ccc;
border: 1px solid rgba(0, 0, 0, 0.15);
-webkit-box-shadow: 0 6px 12px rgba(0, 0, 0, 0.175);
box-shadow: 0 6px 12px rgba(0, 0, 0, 0.175);
}
.navbar-inverse .navbar-nav .open .dropdown-menu .divider {
background-color: #e5e5e5;
}
.navbar-inverse .navbar-nav .open .dropdown-menu>li>a {
color: #333;
}
.navbar-nav .open .dropdown-menu>li>a {
line-height: 1.42857143;
}
.navbar-nav .open .dropdown-menu>li>a,
.navbar-nav .open .dropdown-menu .dropdown-header {
padding: 3px 20px;
}
.navbar-right .dropdown-menu {
right: 0;
left: auto;
}
}
#media only screen and (max-width: 559px) {
.collapse {
display: none;
}
.navbar-header {
display: block;
}
}
</style>
<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">Link <span class="sr-only">(current)</span></li>
<li>Link</li>
<li class="dropdown">
Dropdown <span class="caret"></span>
<ul class="dropdown-menu">
<li>Action</li>
<li>Another action</li>
<li>Something else here</li>
<li role="separator" class="divider"></li>
<li>Separated link</li>
<li role="separator" class="divider"></li>
<li>One more separated link</li>
</ul>
</li>
</ul>
<ul class="nav navbar-nav navbar-right">
<li>Link</li>
<li class="dropdown">
Dropdown <span class="caret"></span>
<ul class="dropdown-menu">
<li>Action</li>
<li>Another action</li>
<li>Something else here</li>
<li role="separator" class="divider"></li>
<li>Separated link</li>
</ul>
</li>
</ul>
</div>
<!-- /.navbar-collapse -->
</div>
<!-- /.container-fluid -->
</nav>