JSFiddle - React, Tailwind, and code Playground

HTML

<header id="header"> cabecera </header>

<section id="contenido"> 
	<article> caja1 </article> 
	<article> caja2 </article>
    <article> caja3 </article>
    <article> caja4 </article>
</section>

CSS

body {
	background: #48870a;
    margin: 0;
}


#header {
	width: 100%;
	height: 70px;
	background: #5cc2b0;
		margin: none;
    padding-left: -10px;
	
}

#contenido {
  width: 80%;
  background: white;
  margin: 0 auto;
}

article {
	width: 20%;
	height: 150px;
	background: orange;
	margin: none;
	display:inline-block;	
}