body { margin: 0; }

nav {
	--width: 130px;
	--height: 40px;
	position: fixed;
	top: 20px;
	left: calc(50% - var(--width) / 2);
	display: grid;
	width: var(--width);
	grid: var(--height) / auto-flow;
	justify-content: space-evenly;
	align-items: center;
	border-radius: calc(var(--height) / 2);
	font: 500 15px -apple-system, BlinkMacSystemFont, sans-serif;
	background: white;
  box-shadow: 0 3px 7px rgba(0, 0, 0, .1);
}
nav a {
	color: #2DBAE7;
	text-decoration: none;
  -webkit-tap-highlight-color: transparent;
}

section { height: 100vh }
#foo { background: #48DC6B; }
#bar { background: #FFBF00; }
#baz { background: #616AFF; }