JSFiddle - React, Tailwind, and code Playground

HTML

<div id="container">
    <div id="help_panel">
        Content goes here.
    </div> 
</div>

CSS

#container{
    width:960px;
    height:400px;
    background:#ccc;
    margin:0 auto;
}

#help_panel{
    position:absolute;
    left:0;
    right:0;
    height:100px;
    background:red;
    color:white;
}