JSFiddle - React, Tailwind, and code Playground

HTML

<body>
    <div class="inicio_m"></div>
    <div id="menu">
        <div id="cab_menu" class="clearfix">
            <div class="conteudo_menu clearfix">	<a href="#1">Item 1</a>
	<a href="#2">Item 2</a>
	<a href="#3">Item 3</a>
	<a href="#4">Item 4</a>

            </div>
        </div>
    </div>
</body>

CSS

html, body {
    height: 100%;
    width: 100%;
}
#menu {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 100;
    background: #000000;
}
#cab_menu {
    width: 100%;
    position: relative;
}
#cab_menu a {
    font-size: 12px;
    font-weight: bold;
    padding: 20px 10px;
    float: left;
    color: #FFFF40;
}
.clearfix {
    display: block;
}
.conteudo_menu {
    width: 100%;
    margin: 0 auto;
}