Bootstrap 4 navbar layout works using CDN, breaks using downloaded code - html

Question

Navbars load collapsed and improperly formatted using downloaded Bootstrap 4 Alpha code, but appear fine using the Bootstrap 4 Alpha CDN. Using the downloaded code is necessary for this project.
Navbar appearance using downloaded Bootstrap 4 Alpha code:
View image
Navbar appearance using Bootstrap 4 Alpha CDN (the look I want): View image
This is my HTML, it doesn't change:
<nav class="navbar navbar-expand-lg navbar-light">
<div class="container">
<a class="navbar-brand" href="#">Brand</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="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navbarSupportedContent">
<ul class="navbar-nav ml-auto">
<li class="nav-item active">
<a class="nav-link" href="#">About Us <span class="sr-only">(current)</span></a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Meet the Team</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Log In</a>
</li>
</ul>
</div>
</div>
</nav>
No idea what's wrong or how to fix this. Anyone familiar with this issue? Thanks

Answer 1

From Bootstrap 4 alpha 6 to beta, navbar-toggleable-* changed to navbar-expand-*, so if you're using navbar-expand-* with alpha it wouldn't work.
If you want it to work in alpha 6, it would be:
<nav class="navbar navbar-toggleable-md navbar-light">..</nav>
If you want it to work in beta, it would be:
<nav class="navbar navbar-expand-lg navbar-light">..</nav>