JSFiddle - React, Tailwind, and code Playground

HTML

<div id="wrapper">
    <div id="content">
        <section class="regular">
            <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Quisque vitae est ut nunc iaculis luctus vitae in risus. Proin mollis facilisis ligula, sed elementum odio consequat quis. Sed at diam urna, vulputate egestas dui. Aenean vehicula fringilla dapibus. Fusce aliquet rhoncus leo, vel tempus mi auctor ultricies.</p>
        </section>
        <section class="full-width">
            <p>This section should extend all the way to the sides of the browser window. This section should extend all the way to the sides of the browser window. This section should extend all the way to the sides of the browser window. This section should extend all the way to the sides of the browser window.</p>
        </section>
        <section>
            <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Quisque vitae est ut nunc iaculis luctus vitae in risus. Proin mollis facilisis ligula, sed elementum odio consequat quis. Sed at diam urna, vulputate egestas dui. Aenean vehicula fringilla dapibus. Fusce aliquet rhoncus leo, vel tempus mi auctor ultricies.</p>
        </section>
    </div>
</div>

CSS

html, body {
    background-color: #DDD;
    margin:0;
}
#wrapper, #content {
    width: 100%;
}
section {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
    background-color: #FFF;
    padding: 1em;
    box-sizing:border-box;
}
section.full-width {
    background-color: #333;
    color: #EEE;
    width: 100%;
    max-width: inherit;
}