@charset "UTF-8";

* {
	box-sizing: border-box;
}

body {
	background: #fff1f1;
	color: #ffffff;
	display: flex;
	flex-direction: column;
	min-height: 100vh;
	margin: 0;
	min-width: 320px;
}

a {
	color: inherit;
	text-decoration: none;
}

button {
	font: inherit;
}

.header {
	background: #711622;
	color: #ffffff;
	position: sticky;
	top: 0;
	z-index: 20;
}

.header__inner,
.menu-overlay__header {
	align-items: center;
	display: flex;
	justify-content: space-between;
	margin: 0 auto;
	max-width: 1280px;
	min-height: 86px;
	padding: 10px 20px;
}

.header__logo,
.menu-overlay__logo {
	font-size: clamp(1.6rem, 2.9vw, 2.25rem);
	letter-spacing: 0.03em;
	line-height: 1;
	white-space: nowrap;
}

.header__nav {
	align-items: center;
	display: flex;
	gap: clamp(18px, 3vw, 56px);
	min-width: 0;
}

.header__nav-link {
	font-size: clamp(0.95rem, 1.9vw, 1.5rem);
	line-height: 1;
	white-space: nowrap;
}

.menu-button,
.menu-close {
	align-items: center;
	background: transparent;
	border: 0;
	color: inherit;
	cursor: pointer;
	display: inline-flex;
	flex-direction: column;
	gap: 17px;
	justify-content: center;
	padding: 0;
}

.menu-button {
	background: #711622;
	height: 70px;
	width: 93px;
}

.menu-button span {
	background: currentColor;
	display: block;
	height: 5px;
	width: 80px;
}

.menu-overlay {
	background: rgba(113, 22, 34, 0.96);
	inset: 0;
	color: #ffffff;
	opacity: 0;
	pointer-events: none;
	position: fixed;
	transition: opacity 0.2s ease;
	z-index: 30;
}

.menu-overlay[aria-hidden="false"] {
	opacity: 1;
	pointer-events: auto;
}

.menu-close {
	gap: 0;
	height: 70px;
	position: relative;
	width: 93px;
}

.menu-close span {
	background: currentColor;
	display: block;
	height: 4px;
	position: absolute;
	width: 38px;
}

.menu-close span:first-child {
	transform: rotate(45deg);
}

.menu-close span:last-child {
	transform: rotate(-45deg);
}

.menu-overlay__nav {
	display: grid;
	gap: 20px;
	margin: 0 auto;
	max-width: 1280px;
	padding: 36px 24px;
}

.menu-overlay__nav a {
	font-size: clamp(1.2rem, 4vw, 1.8rem);
	line-height: 1.4;
}

.album-cover {
	display: flex;
	align-items: center;
	flex: 1 0 auto;
	justify-content: center;
	margin: 0 auto;
	max-width: 1280px;
	padding: 12px 20px 4px;
}

.album-cover__book {
	background: #0c1d44; /* 初期の紺色に戻す */
	border-radius: 30px; /* 初期の角丸30pxに戻す */
	aspect-ratio: 1 / 1.41421356;
	max-height: none;
	max-width: none;
	container-type: size;
	position: relative;
	width: min(616px, calc(100vw - 40px), calc((100vh - 255px) / 1.41421356));
	/* 本の立体シャドウと革の厚み */
	box-shadow: 
		-8px 12px 35px rgba(0, 0, 0, 0.45), 
		inset -4px -4px 10px rgba(0, 0, 0, 0.5), 
		inset 4px 4px 10px rgba(255, 255, 255, 0.1);
	overflow: hidden;
	user-select: none;
	-webkit-user-select: none;
}

/* 金箔押しの二重枠の表現 */
.album-cover__book::before {
	content: "";
	position: absolute;
	inset: 4%;
	border: 1px double rgba(223, 179, 62, 0.45);
	border-radius: 12px;
	pointer-events: none;
	z-index: 2;
}

.album-cover__school,
.album-cover__grade,
.album-cover__label {
	color: #dfb33e; /* 金箔を模したゴールド */
	line-height: 1;
	margin: 0;
	writing-mode: vertical-rl;
	text-orientation: upright;
	z-index: 3;
	/* 金箔押しの凹凸と金属反射を再現する立体シャドウ */
	text-shadow: 
		0.5px 0.5px 0px rgba(255, 255, 255, 0.25), 
		-0.5px -0.5px 0px rgba(0, 0, 0, 0.55), 
		0px 2px 4px rgba(0, 0, 0, 0.3);
}

.album-cover__school {
	font-size: 3.896cqw;
	position: absolute;
	right: 12.8%;
	top: 8.2%;
	white-space: nowrap;
}

.album-cover__grade {
	font-size: 3.896cqw;
	line-height: 1.12;
	left: 50%;
	position: absolute;
	top: 17.4%;
	transform: translateX(-50%);
	writing-mode: horizontal-tb;
	text-align: center;
	white-space: nowrap;
}

.album-cover__label {
	font-size: 5.1948cqw;
	left: 50%;
	position: absolute;
	top: 40.8%;
	transform: translateX(-50%);
	white-space: nowrap;
}

.album-cover__open {
	bottom: 7%;
	right: 8%;
	font-size: 3.246cqw;
	position: absolute;
	white-space: nowrap;
	color: #dfb33e;
	z-index: 4;
	transition: transform 0.25s cubic-bezier(0.25, 1, 0.5, 1);
	text-shadow: 
		0.5px 0.5px 0px rgba(255, 255, 255, 0.25), 
		-0.5px -0.5px 0px rgba(0, 0, 0, 0.55), 
		0px 2px 4px rgba(0, 0, 0, 0.3);
}

.album-cover__open:hover {
	transform: scale(1.05);
}

.footer {
	align-items: center;
	background: #711622;
	color: #ffffff;
	display: flex;
	justify-content: center;
	min-height: 96px;
	padding: 14px 24px;
	position: relative;
}

.footer__top {
	font-size: clamp(1.05rem, 2.5vw, 2rem);
	line-height: 1;
}

.footer p {
	bottom: 24px;
	font-size: clamp(0.95rem, 2vw, 1.5rem);
	margin: 0;
	position: absolute;
	right: 20px;
	white-space: nowrap;
}

@media (max-width: 900px) {
	.header__nav-link {
		display: none;
	}

	.album-cover {
		padding-inline: 14px;
	}

	.album-cover__book {
		width: min(616px, calc(100vw - 28px), calc((100vh - 269px) / 1.41421356));
	}

	.footer {
		min-height: 110px;
	}

	.footer p {
		bottom: 16px;
		right: 16px;
	}
}

@media (max-width: 560px) {

	.header__inner,
	.menu-overlay__header {
		min-height: 72px;
		padding: 8px 14px;
	}

	.menu-button,
	.menu-close {
		height: 56px;
		width: 72px;
	}

	.menu-button span {
		height: 4px;
		width: 52px;
	}

	.album-cover {
		padding: 10px 10px 12px;
	}

	.album-cover__book {
		border-radius: 22px;
		width: min(616px, calc(100vw - 20px), calc((100vh - 218px) / 1.41421356));
	}

	.album-cover__school {
		right: 40px;
		top: 42px;
	}

	.album-cover__grade {
		top: 92px;
	}

	.album-cover__label {
		top: 215px;
	}

	.footer {
		flex-direction: column;
		gap: 14px;
		min-height: 98px;
	}

	.footer p {
		position: static;
	}
}