JSFiddle - React, Tailwind, and code Playground

HTML

<body>
	<button id='boton'>Mostrar menu</button>
	<nav id='menu'></nav>
</body>

CSS

html,body {
    margin:0;
    padding:0;
    width:100%;
    height:100%;
}
#boton {
    height:5%;
    width:25%;
}
#menu {
    display:none;
    width:0%;
    height:95%;
    background:#CDCDCD;
}

JavaScript

$(document).ready(function(){
	$('#boton').click(function(){
		if($('#menu').css('width')<="0px") {
			$('#menu').show();
			$('#menu').animate({width:'25%'});
			$('#boton').html("Ocultar menu");
		} else {
			$('#menu').animate({width:'0%'});
			$('#boton').html("Mostrar menu");
			}
	});
});