html, body {
	height: 100%;
	margin:0;
	padding:0;
}

header, footer {
	position: fixed;
	width: 100%;
	z-index: 99;
}

header {
	top: 0;
}

header ul {
	max-height: 70vw
}

header ul.open {
	overflow-y: scroll;
}

main {
	position: fixed;
	width: 100%;
	top: 39px;
	height: calc(100% - 99px);
}

footer {
	bottom: 0;
	display: flex;
	justify-content: center;
	align-items: center;
	gap: 2rem;
}

.y-scroll {
	overflow-y: scroll;
}