JSFiddle - React, Tailwind, and code Playground

by Jerry Peng

HTML

<body>
    <header id="header">
        <nav>
            <ul id="main">
                <li><a href="#">Home</a>

                </li>
                <li>	<a href="#">About</a>

                    <ul class="hidden">
                        <li><a href="#">About 1</a>

                        </li>
                        <li><a href="#">About 2</a>

                        </li>
                        <li><a href="#">About 3</a>

                        </li>
                    </ul>
                </li>
                <li>	<a href="#">Services</a>

                    <ul class="hidden">
                        <li><a href="#">Services 1</a>

                        </li>
                        <li><a href="#">Services 2</a>

                        </li>
                        <li><a href="#">Services 3</a>

                        </li>
                    </ul>
                </li>
                <li>	<a href="#">History</a>

                    <ul class="hidden">
                        <li><a href="#">The History of This Site</a>

                        </li>
                        <li><a href="#">The History of The Web</a>

                        </li>
                        <li><a href="#">The History of Whatever</a>

                        </li>
                    </ul>
                </li>
                <li><a href="#">Contact</a>

                </li>
            </ul>
        </nav>
    </header>
</body>

CSS

body {
    margin:0;
    padding:0;
    height:1000px;
    background: #39a;
    font-family:arial;
}
header {
    z-index:2;
    position: fixed;
    width: 100%;
    height: 60px;
    background: #222;
}
nav {
    float:left;
}
nav ul {
    list-style-type:none;
    margin:0;
    padding:0;
}
nav ul li {
    display:inline-block;
    float:left;
}
nav ul li a {
    display:block;
    width:80px;
    height:60px;
    text-align:center;
    text-decoration:none;
    line-height:60px;
    color:white;
    background:#404040;
}
nav ul li a:hover {
    background:darkgray;
}
nav ul li:hover ul {
    display:block;
}
nav ul li:hover ul a {
    background:#404040;
    color:white;
    height:60px;
    line-height:60px;
}
ul.hidden {
    display:none;
    position:absolute;
    border-top:white solid 2px;
}
ul.hidden li {
    display:block;
    float:none;
}
ul.hidden li a {
    width:auto;
    min-width:80px;
    padding:0 20px;
}
ul.hidden li a:hover {
    background:darkgray;
}

JavaScript

$(document).ready(function () {
    var width = $(window).width();
    if (width > 800) {
        $('ul li').hover(function () {
            $('ul.hidden'.this).filter(':not(:animated)').slideDown(500);
        },

        function () {
            $('ul.hidden'
            this).fadeOut(500);
        });
    }
});