.sub-menu-parent {
	position: relative;
}

.sub-menu {
	visibility: hidden;
	position: absolute;
	top: 100%;
	left: 0;
	width: 100%;
	transform: translateY(-2em);
	z-index: -1;
	transition: all 0.3s ease-in-out 0s, visibility 0s linear 0.3s, z-index 0s linear 0.01s;
}

.sub-menu-parent:focus .sub-menu,
.sub-menu-parent:focus-within .sub-menu,
.sub-menu-parent:hover .sub-menu {
	visibility: visible;
	opacity: 1;
	z-index: 1;
	transform: translateY(0%);
	transition-delay: 0s, 0s, 0.3s;
}

/* presentational */

nav a {
	display: block;
	padding: 0.5em 1em;
	text-decoration: none;
}

nav a:hover {
	color: #F55;
}

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

nav>ul {
	text-align: center;
}

nav>ul>li {
	display: inline-block;
	border-left: solid 1px #aaa;
}

nav>ul>li:first-child {
	border-left: none;
}

.sub-menu {
	background: #DDD;
}