JSFiddle - React, Tailwind, and code Playground

HTML

<div id="Header">A Header</div>
<div id="divBody">
    <div id="divLeft">
        <div id="divNavContent">
            <div id="topNav">
                <div id="topNavHeader">
                    <label id="topNavHeaderLabel"></label>
                </div>
                <div id="topNavHideButton">
                    <button id="btnHide">Hide Me!</button>
                </div></div><div id="sidebar">
            <ul id="nav">
                <li>LI 1</li>
                <li>LI 2</li>
                <li>LI 3</li>
            </ul>
            </div>
        </div>
        <div id="divNavHidden">
            <div id="btnShowMenu">S<br />h<br />o<br />w<br /> <br />M<br />e<br />n<br />u<br />
            </div>
        </div>
    </div>
    <div id="content">
        Blah: <select id="sel1"></select><br/>Blah: <select id="sel2"></select><br />Blah: <select id="sel3"></select>
    </div>
</div>

CSS

#Header
{
    height: 28px;
    font-size:x-large;
    font-family: Verdana;
    font-style:normal;
    color:White;
    font-weight:bold;
    text-align: left;
    border-color:Blue;
    background-color: Red
}

#divLeft
{
    float: left;
    margin-right: 3px;
}

#sidebar
{
    width: 200px;
}

#topNav
{
    height:30px;
    width: 200px;
    border: 1px solid #999;
    background: #ccc;
    margin: 0px 0px 0px 0px;
    padding: 0;
    font-size:large;
    font-family: Verdana;
    font-style:normal;
    color: White;
    background-color: Green;
}

#topNavHeader
{
    float:left;
    line-height: 30px;
}
#topNavHideButton
{
    float: right;
}

#nav
{
    width: 200px;
    border-top: 1px solid #999;
    border-right: 1px solid #999;
    border-left: 1px solid #999;
    list-style: none;
    margin: 0px 0px 0px 0px;
    padding: 0;
}

#divNavContent
{
    width:200px;
    float:left;
}

#divNavHidden
{
    float: left;
    width: 20px;
    display: none;
    background-color: #C5DCE8;
    text-align: center;
}

#content
{
    float:left;
}

JavaScript

$('#btnHide').click(function() {
                            $("#divNavContent").animate({
                                width: 'toggle'
                            }, 1000, function() {
                                $("#divNavHidden").animate({
                                    width: 'toggle'
                                }, 500);
                            });

                        });

                        $('#btnShowMenu').click(function() {
                            $("#divNavHidden").animate({
                                width: 'toggle'
                            }, 500, function() {
                                $("#divNavContent").animate({
                                    width: 'toggle'
                                }, 1000);
                            });
                        });