JSFiddle - React, Tailwind, and code Playground

HTML

<div id="mainContent">
    <div id="bottomContent">
        
        <ul style="font-size:12px">
            <li>Nome da empresa</li>
            <li>Endere&ccedil;o da empresa</li>
            <li>Telefone da empresa</li>
        </ul>
        <span class="RodapeDireita">
            &copy;Copyright da Empresa
        </span>
  
    </div>
</div>

CSS

#mainContent {
	width:70%;
	margin:auto;
}

#bottomContent {
	z-index:-1;
	height:50px;
	text-align:center;
	color:#000;
    background: #e8e8e8;
    position:relative;
}
ul {
    list-style:none;
}
.RodapeDireita {
	font-size:10px;
	z-index:1;
	bottom:5px;
    right:5px;
    position:absolute;
}