JSFiddle - React, Tailwind, and code Playground

HTML

<div class="outer">
    <div class="inner">
        hello<br/>hello<br/>hello
    </div>
</div>

CSS

body {
    margin: 0;
}
.outer {
    height: 100vh; /*for demo only*/
    background: teal;
    overflow: auto;
}
.inner {
    width: 80%;
    background: gold;
    margin: auto;
    margin-top: 10%; /* 100%-80%/2 */
}