JSFiddle - React, Tailwind, and code Playground

HTML

<body>
    <section id="top">
        postal address...
    </section>
    
    <header id="header">
        logo...
    </header>
</body>

CSS

html { background: #a1a1a1; }

body { 
height: 30em; 
width: 80%; 
margin: 0 auto; 
position: relative; 
background: green;
}


#header {
height: 10em;
background: #ffffff;
margin: 0 -12.5%; 
padding: 0 12.5%;
}