JSFiddle - React, Tailwind, and code Playground

HTML

<div id="navigation">
    <li><a href="">Item 01</a></li>
    <li><a href="">Item 02</a></li>
    <li><a href="">Item 03</a></li>
    <li><a href="">Item 04</a></li>
    <li><a href="">Item 05</a></li>
</div>

CSS

#navigation {
    list-style-type: none;
    margin: 0;
    padding: 0;
    vertical-align: middle;
    line-height: 50px;
    font-size: 0;
    text-align: center;
    background: #cecece
}

#navigation a {
    text-decoration: none;
    display: inline-block;
    padding-bottom: 15px;
    color: #383838;
    webkit-transition: color 0.4s;
    -moz-transition: color 0.4s;
    -ms-transition: color 0.4s;
    -o-transition: color 0.4s;
    transition: color 0.4s;
}

#navigation a:hover {
    color: #6A98DD;
}

#navigation li {
    display: inline-block;
    padding-left: 9px;
    padding-right: 10px;
    color: #383838;
    background: #EEE;
    font-size: 13px;
    webkit-transition: color 0.4s;
    -moz-transition: color 0.4s;
    -ms-transition: color 0.4s;
    -o-transition: color 0.4s;
    transition: color 0.6s;
    webkit-transition: background 0.4s;
    -moz-transition: background 0.4s;
    -ms-transition: background 0.4s;
    -o-transition: background 0.4s;
    transition: background 0.4s;
}

#navigation li:hover {
    padding-left: 8px;
    color: #6A98DD;
    display: inline-block;
    background: #EEE;
    border-left: 1px solid #AAA;
}