JSFiddle - React, Tailwind, and code Playground

HTML

<h2 class="section-heading">Example</h2>

CSS

.section-heading {
  display: table;
  white-space: nowrap;
}

.section-heading:before {
  background: linear-gradient(to bottom, black, black) no-repeat left center / 95% 1px;
  content: "";
  display: table-cell;
  width: 50%;
}

.section-heading:after {
  background: linear-gradient(to bottom, black, black) no-repeat right center / 95% 1px;
  content: "";
  display: table-cell;
  width: 50%;
}