JSFiddle - React, Tailwind, and code Playground

HTML

<section class="outer-flex-container">

    <div class="attempt">

    </div>

    <section class="inner-flex-container">
        <div>
            <ul id="menu">
                <li><a style="background:#3F4E64" href="/html/default.asp">Button1</a></li>
                <li><a style="background:#788291">Button2</a></li>
            </ul>
        </div>

        <div>
            <H2>TITLE</H2>
            <p>
                BADKADA
            </p>
            <p>
                Fusce luctus ipsum in dui accumsan, posuere scelerisque lacus ultrices. Quisque quis ultricies nunc. Nam augue magna, eleifend id mi vel, pretium
            </p>
            <p>
                Fusce luctus ipsum in dui accumsan, posuere scelerisque lacus ultrices. Quisque quis ultricies nunc. Nam augue magna, eleifend id mi vel, pretium
            </p>

            <p>
                Fusce luctus Fusce luctus ipsum in dui accumsan, posuere scelerisque lacus ultrices. Quisque quis ultricies nunc. Nam augue magna, eleifend id mi vel, pretium fring.
            </p>
        </div>

        <div>
            <H2>TITLE</H2>
            <p>
                BADKADA
            </p>
            <p>
                Fusce luctus ipsum in dui accumsan, posuere scelerisque lacus ultrices. Quisque quis ultricies nunc. Nam augue magna, eleifend id mi vel, pretium
            </p>
            <p>
                Fusce luctus ipsum in dui accumsan, posuere scelerisque lacus ultrices. Quisque quis ultricies nunc. Nam augue magna, eleifend id mi vel, pretium
            </p>

            <p>
                Fusce luctus Fusce luctus ipsum in dui accumsan, posuere scelerisque lacus ultrices. Quisque quis ultricies nunc. Nam augue magna, eleifend id mi vel, pretium fring.
            </p>
        </div>
    </section><!-- END .inner-flex-container -->
</section><!-- END .outer-flex-container -->

CSS

.outer-flex-container {
    display: flex;
}

.attempt {
    width: 15px;
    background: #3F4E64;
    margin-right: 20px;
}