Changing class from navbar-light to navbar-dark hides navbar

Question

I am building a website using Laravel and the Bootstrap CSS framework. I have a navbar at the top of the page which is used for navigating across different pages. By default, the Laravel set the navbar class to navbar-light. Since I don't want the navbar to be white, I changed it to navbar-dark. When I do this, all the content from navbar disappears, there remains only white bar without any content. What am I doing wrong?

<nav class="navbar navbar-expand-md navbar-dark navbar-laravel" style="margin-bottom: 20px;">
    <div class="container">
        <a class="navbar-brand" href="{{ url('/') }}">
        {{ config('app.name', 'Laravel') }}
        </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">
            <!-- Left Side Of Navbar -->
            <ul class="navbar-nav mr-auto">
                <li class="nav-item">
                    <a class="nav-link" href="/">Home <span class="sr-only">(current)</span></a>
                </li>
                <li class="nav-item">
                    <a class="nav-link" href="#">Messages <span class="sr-only">(current)</span></a>
                </li>
                <li class="nav-item">
                    <a class="nav-link" href="#">People <span class="sr-only">(current)</span></a>
                </li>
                <li class="nav-item">
                    <a class="nav-link" href="#">Photos <span class="sr-only">(current)</span></a>
                </li>
            </ul>
            <!-- Right Side Of Navbar -->
            <ul class="navbar-nav ml-auto">
                <!-- Authentication Links -->
                @guest
                <li><a class="nav-link" href="{{ route('login') }}">Login</a></li>
                <li><a class="nav-link" href="{{ route('register') }}">Register</a></li>
                @else
                <li class="nav-item dropdown">
                    <a class="nav-link dropdown-toggle" href="#" role="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
                    {{ Auth::user()->name }} <span class="caret"></span>
                    </a>
                    <div class="dropdown-menu" aria-labelledby="navbarDropdown">
                        <a class="dropdown-item" href="dashboard">
                        Dashboard
                        </a>
                        <a class="dropdown-item" href="{{ route('logout') }}"
                            onclick="event.preventDefault();
                            document.getElementById('logout-form').submit();">
                        Logout
                        </a>
                        <form id="logout-form" action="{{ route('logout') }}" method="POST" style="display: none;">
                            @csrf
                        </form>
                    </div>
                </li>
                @endguest
            </ul>
        </div>
    </div>
</nav>

Solution

You also need to add the class bg-dark additionally to navbar-dark.

navbar-dark basically just determines what color the text should be i.e. light text for a dark-background navbar and dark text for a light-colored navbar.

bg-dark then determines the actual background-color of the navbar. But other colors would work just as well. For example, bg-primary or bg-danger would work well with navbar-dark.

Comments

[Gerardo BLANCO]

Welcome to Stack Overflow! Questions seeking debugging help should include the desired behavior, a specific problem or error and the shortest code necessary to reproduce it within the question itself. Questions without a clear problem statement are not useful to other readers. Please see: How to create a Minimal, Complete, and Verifiable example.

[Hackerman]

Which version of Bootstrap?

[PhotoJorie]

If I open public/css/app.css, it says that the version is 4.0.0 at the top of the file (in the comment section).