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

body {
	font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
	background-color: #1a0b2e;
	background-image: linear-gradient(160deg, #1a0b2e 0%, #3d1155 100%);
	color: #f5f2fa;
}

.book-container {
	display: flex;
	min-height: 100vh;
}

.chapter-list {
	width: 26%;
	min-width: 220px;
	background-color: rgba(0, 0, 0, 0.2);
	padding: 20px;
	box-sizing: border-box;
	overflow-y: auto;
}

.book-tabs {
	display: flex;
	margin-bottom: 15px;
	border-bottom: 2px solid rgba(255, 255, 255, 0.2);
}

.book-tab {
	flex: 1;
	text-align: center;
	padding: 10px;
	cursor: pointer;
	font-weight: bold;
	font-size: 0.9rem;
	color: #f5f2fa;
	background-color: rgba(255, 255, 255, 0.05);
}

.book-tab.active {
	background-color: rgba(255, 255, 255, 0.1);
	border-bottom: 3px solid #c9a4ff;
	color: #c9a4ff;
}

.book-tab:hover {
	color: #c9a4ff;
}

.chapter-title {
	display: block;
	padding: 10px 16px;
	background-color: rgba(255, 255, 255, 0.06);
	border: 1px solid rgba(255, 255, 255, 0.12);
	border-radius: 4px;
	cursor: pointer;
	margin-bottom: 6px;
	font-size: 0.9rem;
	color: #f5f2fa;
}

.chapter-title.active {
	background-color: rgba(201, 164, 255, 0.18);
	border-color: #c9a4ff;
	color: #fff;
}

.chapter-title:hover {
	color: #c9a4ff;
}

.main-content {
	flex: 1;
	padding: 20px;
	box-sizing: border-box;
	display: flex;
	flex-direction: column;
}

.page-title {
	margin: 0;
	margin-bottom: 20px;
	font-size: 1.6rem;
	font-weight: bold;
	text-align: center;
	color: #fff;
}

.iframe-container {
	flex: 1;
	overflow-y: auto;
	background-color: #fff;
	border-radius: 6px;
}

iframe {
	width: 100%;
	height: 100%;
	min-height: 70vh;
	border: none;
}

@media (max-width: 720px) {
	.book-container {
		flex-direction: column;
	}

	.chapter-list {
		width: 100%;
		min-width: 0;
		max-height: 40vh;
	}
}