header {
	position: fixed;
	width: 100%;
	top: 0;
	left: 0;
	z-index: 100;
	padding: 0 3rem;
}

header::before {
	content: '';
	position: absolute;
	top: 0;
	left: 0;
	width: 100%;
	height: 100%;
	background: rgba(255, 255, 255, 0.5);
	backdrop-filter: blur(10px);
	-webkit-backdrop-filter: blur(10px);
	opacity: 0;
	transition: opacity 0.3s;
	z-index: -1;
}

header.open::before {
	opacity: 1;
}

nav {
	display: flex;
	align-items: center;
	padding: 1.5rem 0;
}

nav > h1 {
	font-size: 2rem;
	font-weight: 900;
	font-style: italic;
	margin: 0 auto 0 1rem;
	font-family: 'Merriweather', serif;
}

/* nav > h1 img {
	height: 1em;
	vertical-align: initial;
} */

nav .header-btn {
	width: 3.6rem;
	height: 3.6rem;
	padding: 0;
	margin: 0;
	border: none;
	box-shadow: none;
	background: transparent;
}

nav a.header-btn {
	mask: var(--ico) no-repeat center center;
	mask-size: 90%;
	-webkit-mask: var(--ico) no-repeat center center;
	-webkit-mask-size: 90%;
	background: var(--text-color);
}

nav .header-btn:last-child {
	margin-left: 1.6rem;
}

nav .menu-btn {
	position: relative;
	width: 2.4rem;
	height: 2.4rem;
	animation: menuBlink 0.7s infinite linear alternate;
}

@keyframes menuBlink {
	from {
		opacity: 1;
	}
	to {
		opacity: 0;
	}
}

nav .menu-btn span {
	position: absolute;
	top: 50%;
	left: 50%;
	transform: translate(-50%, -50%);
	width: 1rem;
	height: 1rem;
	background: var(--text-color);
	border-radius: 100%;
}

header.open nav .menu-btn {
	animation: none;
}

header.open nav .menu-btn span {
	width: 90%;
	height: 1px;
	border-radius: 1px;
}

header.open nav .menu-btn span:first-child {
	transform: translate(-50%, -50%) rotate(45deg);
}
header.open nav .menu-btn span:last-child {
	transform: translate(-50%, -50%) rotate(-45deg);
}

ul.header-menu {
	display: flex;
	align-items: center;
	border-top: 1px solid var(--text-color);
	padding: 0.6rem 0 1rem 3.4rem;
	font-size: 1.2rem;
	font-weight: 300;
	visibility: hidden;
	opacity: 0;
	transition: all 0.3s;
}

header.open ul.header-menu {
	opacity: 1;
	visibility: visible;
}

ul.header-menu > li {
	position: relative;
	margin-right: 2.4rem;
	font-family: 'Merriweather', serif;
}

ul.header-menu > li::before,
ul.header-menu > li::after {
	position: absolute;
	opacity: 0;
	transition: opacity 0.3s;
	pointer-events: none;
}
ul.header-menu > li::before {
	content: '「';
	left: 0;
	transform: translateX(-130%);
}
ul.header-menu > li::after {
	content: '」';
	right: 0;
	transform: translateX(130%);
}
ul.header-menu > li:hover::before,
ul.header-menu > li:hover::after {
	opacity: 1;
}

@media screen and (max-width: 768px) {
	header {
		padding: 0 2rem;
		height: 6rem;
	}

	header.open {
		height: auto;
	}

	header::before {
		background: var(--bg-color);
		backdrop-filter: initial;
	}

	nav > h1 {
		font-size: 1.6rem;
	}

	nav .header-btn {
		width: 2.4rem;
		height: 2.4rem;
	}

	ul.header-menu {
		flex-direction: column;
		align-items: flex-start;
		border-top: none;
		padding: 5rem 2rem 4rem;
		font-size: 1.4rem;
		pointer-events: none;
	}

	header.open ul.header-menu {
		pointer-events: auto;
	}

	ul.header-menu > li {
		margin-right: 0;
		margin-bottom: 2.5rem;
	}

	ul.header-menu > li:last-child {
		margin-bottom: 0;
	}
}