Nav-pill Positioning

I would like to create a side-bar menu with the Bootstrap 4 framework. Utilizing their default nav-pills how can I position two pills on the same row? Please find below the default

Solution 1:

Implementation details may vary but I would approach this with something like below.

#tab-sidebar .nav-link {
    margin: 5px;
    border: 1px solid lightgray;
    
    /* This is just to center text in pills */
    display: flex;
    justify-content: center;
    align-items: center;
    text-align: center;
}

#tab-sidebar .nav-link.col-6 {
    /* 10px is just double the size of 5px margin set on .nav-link */
    max-width: calc(100% / 2 - 10px);
}

#tab-sidebar .nav-link.col-12 {
    max-width: calc(100% - 10px);
}

<div class="container">
    <div class="row">
        <div id="tab-sidebar" class="col-3 nav nav-pills" role="tablist" aria-orientation="vertical">
            <a id="pill-A" class="nav-link col-6 active" data-toggle="pill" href="#tab-A" role="tab" aria-controls="tab-A" aria-selected="true">A</a>
            <a id="pill-B" class="nav-link col-6" data-toggle="pill" href="#tab-B" role="tab" aria-controls="tab-B" aria-selected="false">B</a>
            <a id="pill-C" class="nav-link col-12" data-toggle="pill" href="#tab-C" role="tab" aria-controls="tab-C" aria-selected="false">C</a>
            <a id="pill-D" class="nav-link col-6" data-toggle="pill" href="#tab-D" role="tab" aria-controls="tab-D" aria-selected="false">Item D with Very Long Name</a>
            <a id="pill-E" class="nav-link col-6" data-toggle="pill" href="#tab-E" role="tab" aria-controls="tab-E" aria-selected="false">Short E</a>
        </div>

        <div id="tab-content" class="col-9 tab-content">
            <div id="tab-A" class="tab-pane fade show active" role="tabpanel" aria-labelledby="pill-A">[A]</div>
            <div id="tab-B" class="tab-pane fade" role="tabpanel" aria-labelledby="pill-B">[B]</div>
            <div id="tab-C" class="tab-pane fade" role="tabpanel" aria-labelledby="pill-C">[C]</div>
            <div id="tab-D" class="tab-pane fade" role="tabpanel" aria-labelledby="pill-D">[D]</div>
            <div id="tab-E" class="tab-pane fade" role="tabpanel" aria-labelledby="pill-E">[E]</div>
        </div>
    </div>
</div>


<link href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta.2/css/bootstrap.min.css" rel="stylesheet"/>
<script src="https://code.jquery.com/jquery-3.2.1.slim.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.3/umd/popper.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta.2/js/bootstrap.min.js"></script>

So I won't use .flex-column in this case, but would rather set the widths of the pills with .col classes. As you can see in the css section, the .cols are slightly altered under the #tab-sidebar selector, in order to take margins between pills into account.