<nav>
  <ul>
    <li><span>Home</span></li>
    <li><span>Products</span></li>
    <li><span>Services</span></li>
    <li><span>Contact</span></li>
  </ul>
</nav>
body {
	margin: 0;
	height: 100vh;
	display: flex;
	align-items: center;
	justify-content: center;
	background: linear-gradient(to right bottom, gold, chocolate);
}

nav ul {
	list-style-type: none;
	padding: 0;
}

nav ul li {
	font-size: 40px;
	font-family: sans-serif;
	background-color: white;
	border: 2px solid black;
	letter-spacing: 0.1em;
	width: 5em;
	height: 1.5em;
	line-height: 1.5em;
	position: relative;
	overflow: hidden;
	margin: 0.5em;
	cursor: pointer;
}

nav ul li span {
	color: white;
	mix-blend-mode: difference;
}

nav ul li::before {
	content: '';
	position: absolute;
	width: 1.5em;
	height: inherit;
	background-color: black;
	border-radius: 50%;
	top: 0;
	left: -0.75em;
	transition: 0.5s ease-out;
}

nav ul li:hover::before {
	transform: scale(7);
}

External CSS

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External JavaScript

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