JSFiddle - React, Tailwind, and code Playground

HTML

<div class="title">
    Title
    <p><a href="http://stackoverflow.com/questions/24466595/css-fill-parent-available-space">Refers to this Stackoverflow question</a></p>
</div>
<div class="content">
    <div class="content-content">
        Content
    </div>
</div>

CSS

html, body {
    height: 100%;
    margin: 0;
}

body {
    display: flex;
    flex-direction: column;
}

.content {
    flex: 1;
}

/* make it visible */

.title {
    background-color: #ddd;
}

.content, .content-content {
    background-color: #eee;
}

JavaScript

// Only used to add overflowing content.

$(".content").click(function(){
    $(this).children().append("<br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br>");
});

$(".title").click(function(){
    $(this).children().append("<br><br><br><br><br><br><br><br><br><br>");
});