/* EB PDF Flipbook — front-end styles */

.ebfb {
	--ebfb-h: 540px;
	display: grid;
	grid-template-columns: auto 1fr auto;
	grid-template-rows: auto auto;
	align-items: center;
	gap: 8px 12px;
	width: 100%;
}

.ebfb--empty {
	display: block;
	padding: 40px;
	text-align: center;
	background: rgba(0, 0, 0, 0.05);
	border: 1px dashed rgba(0, 0, 0, 0.3);
}

/* ---------- Stage & book ---------- */
.ebfb__stage {
	grid-column: 2;
	grid-row: 1;
	position: relative;
	height: var(--ebfb-h);
	display: flex;
	align-items: center;
	justify-content: center;
	perspective: 2400px;
}

.ebfb__book {
	position: relative;
	height: 100%;
	display: flex;
	transform-style: preserve-3d;
}

.ebfb__page {
	position: relative;
	height: 100%;
	background: #ffffff;
	overflow: hidden;
	flex-shrink: 0;
}

.ebfb-shadow-yes .ebfb__book {
	filter: drop-shadow(0 18px 30px rgba(0, 0, 0, 0.35));
}

.ebfb__page canvas {
	display: block;
	height: 100%;
	width: auto;
}

/* Spine hint between the two pages of a spread */
.ebfb__page--left::after,
.ebfb__page--right::before {
	content: "";
	position: absolute;
	top: 0;
	bottom: 0;
	width: 26px;
	pointer-events: none;
}

.ebfb__page--left::after {
	right: 0;
	background: linear-gradient(to left, rgba(0, 0, 0, 0.18), transparent);
}

.ebfb__page--right::before {
	left: 0;
	background: linear-gradient(to right, rgba(0, 0, 0, 0.18), transparent);
}

/* ---------- The turning sheet (3D) ---------- */
.ebfb__sheet {
	position: absolute;
	top: 0;
	height: 100%;
	transform-style: preserve-3d;
	transition: transform 0.85s cubic-bezier(0.4, 0.05, 0.3, 1);
	z-index: 5;
	will-change: transform;
}

.ebfb__sheet--next {
	transform-origin: left center;
}

.ebfb__sheet--prev {
	transform-origin: right center;
}

.ebfb__sheet.is-flipping.ebfb__sheet--next {
	transform: rotateY(-180deg);
}

.ebfb__sheet.is-flipping.ebfb__sheet--prev {
	transform: rotateY(180deg);
}

.ebfb__face {
	position: absolute;
	inset: 0;
	backface-visibility: hidden;
	-webkit-backface-visibility: hidden;
	background: #ffffff;
	overflow: hidden;
}

.ebfb__face canvas {
	display: block;
	height: 100%;
	width: auto;
}

.ebfb__face--back {
	transform: rotateY(180deg);
}

/* Moving shadow on the turning sheet */
.ebfb__face::after {
	content: "";
	position: absolute;
	inset: 0;
	background: rgba(0, 0, 0, 0);
	transition: background 0.85s ease;
	pointer-events: none;
}

.ebfb__sheet.is-flipping .ebfb__face::after {
	background: rgba(0, 0, 0, 0.12);
}

/* Single-page mode swap animation */
.ebfb__page.is-swapping {
	animation: ebfb-swap 0.5s ease;
}

@keyframes ebfb-swap {
	0%   { transform: rotateY(0); }
	50%  { transform: rotateY(9deg) scale(0.98); opacity: 0.6; }
	100% { transform: rotateY(0); }
}

/* ---------- Arrows ---------- */
.ebfb__nav {
	grid-row: 1;
	background: none;
	border: 0;
	padding: 8px;
	cursor: pointer;
	color: #111;
	transition: color 0.25s ease, background 0.25s ease, transform 0.2s ease;
	border-radius: 8px;
	line-height: 0;
}

.ebfb__nav--prev { grid-column: 1; }
.ebfb__nav--next { grid-column: 3; }

.ebfb__nav svg {
	width: 42px;
	height: 42px;
}

.ebfb__nav:hover {
	transform: scale(1.12);
}

.ebfb__nav:disabled {
	opacity: 0.25;
	cursor: default;
	transform: none;
}

/* ---------- Bottom bar: counter + fullscreen ---------- */
.ebfb__bar {
	grid-column: 2;
	grid-row: 2;
	display: flex;
	align-items: center;
	justify-content: center;
	position: relative;
	min-height: 34px;
}

.ebfb__counter {
	font-weight: 800;
	font-size: 18px;
	letter-spacing: 0.05em;
}

.ebfb__fs {
	position: absolute;
	right: 0;
	background: none;
	border: 0;
	padding: 6px;
	cursor: pointer;
	line-height: 0;
	border-radius: 6px;
	transition: color 0.25s ease, background 0.25s ease, transform 0.2s ease;
}

.ebfb__fs svg {
	width: 26px;
	height: 26px;
}

.ebfb__fs:hover {
	transform: scale(1.15);
}

/* ---------- Fullscreen mode ---------- */
.ebfb:fullscreen {
	background: #1e1e1e;
	padding: 4vh 3vw;
	--ebfb-h: 82vh;
}

.ebfb:fullscreen .ebfb__counter,
.ebfb:fullscreen .ebfb__nav {
	color: #ffffff;
}

/* ---------- Loading spinner ---------- */
.ebfb__loading {
	position: absolute;
	inset: 0;
	display: flex;
	align-items: center;
	justify-content: center;
	pointer-events: none;
}

.ebfb__loading.is-hidden {
	display: none;
}

.ebfb__spinner {
	width: 44px;
	height: 44px;
	border: 4px solid rgba(0, 0, 0, 0.15);
	border-top-color: #c8102e;
	border-radius: 50%;
	animation: ebfb-spin 0.9s linear infinite;
}

@keyframes ebfb-spin {
	to { transform: rotate(360deg); }
}

/* ---------- Responsive ---------- */
@media (max-width: 767px) {
	.ebfb {
		gap: 4px 4px;
	}

	.ebfb__nav svg {
		width: 30px;
		height: 30px;
	}

	.ebfb {
		--ebfb-h: 60vw;
	}
}