JSFiddle - React, Tailwind, and code Playground

HTML

<nav>
	<p>
		Menu
	</p>
	<ul>
		<li>
			<a data-scroll href="#why">
				<span>Why</span>
				<span class="small-nav-text">Humanizing healthcare</span>
			</a>
		</li>
		<li>
			<a data-scroll href="#how">
				<span>How</span>
				<span class="small-nav-text">Improving communication</span>
			</a>
		</li>
		<li>
			<a data-scroll href="#tickit">
				<span>TickiT</span>
				<span class="small-nav-text">Our flagship product</span>
			</a>
		</li>
		<li>
			<a data-scroll href="#team">
				<span>Team</span>
				<span class="small-nav-text">The gang</span>
			</a>
		</li>
		<li>
			<a data-scroll href="#contact">
				<span>Contact</span>
				<span class="small-nav-text">Let's talk</span>
			</a>
		</li>
	</ul>
</nav>

CSS

nav li {
  display: inline-block;
}
nav a {
  margin: 0;
  padding: 0 2.1875rem;
  text-align: center;
  font-size: 1.16875rem; }
  nav a:after {
    position: absolute;
    top: 100%;
    left: 0;
    opacity: 0;
    width: 100%;
    height: 1px;
    background: #fff;
    content: '';
    -webkit-transition: -webkit-transform 0.3s, opacity 0.3s, height 0.3s;
    -moz-transition: -moz-transform 0.3s, opacity 0.3s, height 0.3s;
    transition: transform 0.3s, opacity 0.3s, height 0.3s;
    -webkit-transform: translateY(-10px);
    -moz-transform: translateY(-10px);
    transform: translateY(-10px); }
  nav a:hover:before, nav a:focus:before {
    height: 6px; }
  nav a:hover::before, nav a:hover::after, nav a:focus::before, nav a:focus::after {
    opacity: 1;
    -webkit-transform: translateY(0px);
    -moz-transform: translateY(0px);
    transform: translateY(0px); }
  nav a span:first-child {
    z-index: 2;
    display: block; }
  nav a .small-nav-text {
    font-size: 0.875rem;
    z-index: 1;
    display: block;
    padding: 8px 0 0 0;
    color: rgba(0, 0, 0, 0.4);
    text-transform: none;
    opacity: 0;
    position: relative;
    -webkit-transition: -webkit-transform 0.3s, opacity 0.3s;
    -moz-transition: -moz-transform 0.3s, opacity 0.3s;
    transition: transform 0.3s, opacity 0.3s;
    -webkit-transform: translateY(-100%);
    -moz-transform: translateY(-100%);
    transform: translateY(-100%); }
  nav a:hover .small-nav-text, nav a:focus .small-nav-text {
    opacity: 1;
    -webkit-transform: translateY(0%);
    -moz-transform: translateY(0%);
    transform: translateY(0%); }