JSFiddle - React, Tailwind, and code Playground

HTML

<body>
    <div id="header">HEADER</div>
    <div id="content">
        <p>Text1</p>
        <p>Text2</p>
        <p>Text3</p>
        <p>Text4</p>
    </div>
</body>

CSS

body {
    background:#FFD;
}

#header {
    position:fixed;
    height:15px;
    width:100%;
    text-align:center;
    border-bottom:1mm dashed #7F7F7F;
    background-color:#EEE; 
}

#content {
    width:90%;
    margin-top:25px;
    margin-left:auto;
    margin-right:auto;
    background-color:#E5E5FF;
    border: 1px solid #000;
}