JSFiddle - React, Tailwind, and code Playground

HTML

<div id="leftnav">close and open on mobile device</div>

<div id="main-content">content her</div>

<div id="rightnav">close and open on mobile device</div>

CSS

#leftnav{
    height:1000px;
    background-color:grey;
    width:100px;
    float:left;
}
#rightnav{
    height:1000px;
    background-color:red;
    width:100px;
    float:left;
}

#main-content{
    height:1000px;
    background-color:#e5e5e5;
    width:400px;
    float:left;
}