JSFiddle - React, Tailwind, and code Playground

HTML

<body>
<table width="100%">
    <tr>
        <td height="1200">
        </td>
    </tr>
</table>
<div class="header">
    Invoice Number : A23000BN
</div>
</body>

CSS

.header{
            text-align: right;
            height: 20px;
            position:fixed;
            margin:0px;
            top:0px;
        }