JSFiddle - React, Tailwind, and code Playground

HTML

<div class="border">
    <h1>Hello</h1>
</div>

CSS

h1 {
    position: relative;
    bottom: -17px;
    background: #fff;
    padding-right: 10px;
    margin: 0;
    display: inline-block;
}
div.border {
    border-bottom: 1px solid #000;
}