JSFiddle - React, Tailwind, and code Playground

HTML

<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<div id="navbar">

    <ul>
    
        <li class="active"><a href="#" title="Projects">Projects<span class="notification">34</span></a></li>
        <li class="inactive"><a href="#" title="Contacts">Contacts</a></li>
        <li class="inactive"><a href="#" title="Earnings">Earnings</a></li>
        <li class="inactive"><a href="#" title="To-do">To-do<span class="notification">100</span></a></li>
        
    </ul>


</div>

<div id="slider">

    <h2>Projects</h2>
    
    <p>Professionally cultivate stand-alone core competencies whereas distributed web services. Rapidiously streamline bleeding-edge total linkage after multidisciplinary networks. Authoritatively create multifunctional methodologies through premier collaboration and idea-sharing. 

        Phosfluorescently evisculate global manufactured products whereas customized total linkage. Appropriately optimize resource maximizing core competencies via an expanded array of functionalities.</p>
    
    <h2>Contacts</h2>
    
    <p>Professionally cultivate stand-alone core competencies whereas distributed web services. Rapidiously streamline bleeding-edge total linkage after multidisciplinary networks. Authoritatively create multifunctional methodologies through premier collaboration and idea-sharing. 

        Phosfluorescently evisculate global manufactured products whereas customized total linkage. Appropriately optimize resource maximizing core competencies via an expanded array of functionalities.</p>
    
    <h2>Earnings</h2>
    
    <p>Professionally cultivate stand-alone core competencies whereas distributed web services. Rapidiously streamline bleeding-edge total linkage after multidisciplinary networks. Authoritatively create multifunctional methodologies through premier collaboration and idea-sharing. 

        Phosfluorescently evisculate global manufactured products whereas customized total linkage. Appropriately...

CSS

body {
    margin: 0;
    padding: 0;
    font-family: helvetica, tahoma, Sans-serif;
    font-size: 13px;
    background: url(https://dl.dropbox.com/u/2022205/untitled-1.jpg) repeat;
}

a { 
    text-decoration: none;
}

h2 {
    font-family: Helvetica, tahoma, Sans-serif;
    font-size: 25px;
    font-weight: bold;
    text-shadow: 0 1px 1px white;
}

p {
    text-shadow: 0 1px 1px white;
}

#navbar {
    margin: 20px 0 0 40px;
    width: 650px;
    font-weight: bold;
}

/*###########################################
ul li (all)
###########################################*/

ul li{
    display: inline-block;
}

ul li a {
    position: relative;
    display: block;
    width: 150px;
    text-align: center;
}

/*###########################################
Active
###########################################*/

.active a{
    padding: 28px 0 20px 0;
    background: -webkit-gradient(linear, left top, left bottom, from(#db0000), to(#9b0000));
    background: -moz-linear-gradient(top center, #db0000, #9b0000);
    border: 1px solid #8d0000;
    text-shadow: 0 1px 1px black;
    -webkit-border-radius: 10px 10px 0 0;
    -webkit-background-clip: padding-box;
    -webkit-box-shadow: inset 0 0 1px #fd0000;
    -moz-border-radius: 10px 10px 0 0;
    -moz-background-clip: padding-box;
    -moz-box-shadow: inset 0 0 1px #fd0000;
    margin-left: -5px;
    z-index: 2;
    color: white;
    text-shadow: 0 1px 1px black;
}

.active a:focus {
    outline: none;
}

/*###########################################
Inactive
###########################################*/


.inactive a:hover {
    background: -webkit-gradient(linear, left bottom, left top, from(#eee), to(#ddd));
    background: -moz-linear-gradient(top center, #ddd, #eee);
}

.inactive a {
    color: #222;
    text-shadow: 0 1px 1px white;
    background: -webkit-gradient(linear, left top, left bottom, from(#eee), to(#ddd));
    background: -moz-linear-gradient(top center, #eee, #ddd);
    -webkit-box-shadow: inset 0 0 5px...

JavaScript

$(document).ready(function(){

    $('li').click(function(){
        var number = $(this).index();
        $('h2').slideUp(400).eq(number).slideDown(400);
        $('p').slideUp(400).eq(number).slideDown(400);
        $('li').removeClass('inactive').addClass('active');
        $('li').not(this).removeClass('active').addClass('inactive');
    });

    $('h2').not(':first').hide();
    $('p').not(':first').hide();
});