.xuexi-page {
	margin-bottom: 2rem;
	padding-top: 28px;
}

.xuexi-page-head {
	border-bottom: 3px solid #e60115;
	padding-bottom: 10px;
	margin-bottom: 24px;
}

.xuexi-page-head h1 {
	margin: 0;
	font-size: 22px;
	color: #e60115;
	font-weight: bold;
}

.xuexi-page-head p {
	margin: 8px 0 0;
	color: #c40012;
	font-size: 14px;
}

.xuexi-grid {
	display: grid;
	grid-template-columns: repeat(4, 1fr);
	gap: 20px;
}

.xuexi-card {
	display: block;
	background: #fff;
	border: 1px solid #e5e5e5;
	border-radius: 8px;
	overflow: hidden;
	text-decoration: none;
	color: #333;
	box-shadow: 0 1px 4px rgba(0, 0, 0, 0.06);
	transition: box-shadow 0.2s, transform 0.2s;
	cursor: pointer;
}

.xuexi-card:hover {
	box-shadow: 0 6px 16px rgba(0, 51, 153, 0.15);
	transform: translateY(-2px);
	color: #003399;
}

.xuexi-card-thumb {
	height: 160px;
	background: #f5f7fa;
	overflow: hidden;
	display: flex;
	align-items: center;
	justify-content: center;
}

.xuexi-card-thumb img {
	width: 100%;
	height: 100%;
	object-fit: cover;
	display: block;
}

.xuexi-card-thumb--default {
	font-size: 42px;
	font-weight: bold;
	color: #c00;
	letter-spacing: 2px;
}

.xuexi-card-title {
	padding: 12px 14px 14px;
	font-size: 15px;
	line-height: 1.5;
	min-height: 3em;
	display: -webkit-box;
	-webkit-line-clamp: 2;
	-webkit-box-orient: vertical;
	overflow: hidden;
	text-align: left;
}

.xuexi-empty {
	text-align: center;
	padding: 60px 20px;
	color: #999;
	font-size: 15px;
	background: #fafafa;
	border: 1px dashed #ddd;
	border-radius: 8px;
}

.xuexi-modal {
	display: none;
	position: fixed;
	inset: 0;
	z-index: 9999;
	background: rgba(0, 0, 0, 0.55);
}

.xuexi-modal.is-open {
	display: flex;
	align-items: center;
	justify-content: center;
	padding: 20px;
	box-sizing: border-box;
}

.xuexi-modal-inner {
	width: 100%;
	max-width: 1100px;
	height: 90vh;
	background: #fff;
	border-radius: 8px;
	overflow: hidden;
	display: flex;
	flex-direction: column;
	box-shadow: 0 8px 32px rgba(230, 1, 21, 0.25);
	border: 2px solid #e60115;
}

.xuexi-modal-head {
	flex: 0 0 auto;
	display: flex;
	align-items: center;
	justify-content: space-between;
	padding: 12px 16px;
	background: #e60115;
}

.xuexi-modal-head span {
	font-size: 16px;
	font-weight: bold;
	color: #fff;
	overflow: hidden;
	text-overflow: ellipsis;
	white-space: nowrap;
	padding-right: 12px;
}

.xuexi-modal-close {
	flex: 0 0 auto;
	width: 36px;
	height: 36px;
	border: none;
	background: rgba(255, 255, 255, 0.25);
	color: #fff;
	font-size: 24px;
	line-height: 1;
	border-radius: 4px;
	cursor: pointer;
}

.xuexi-modal-close:hover {
	background: rgba(255, 255, 255, 0.45);
}

.xuexi-modal-body {
	flex: 1;
	min-height: 0;
	position: relative;
}

.xuexi-modal-body iframe {
	width: 100%;
	height: 100%;
	border: none;
	display: block;
}

.xuexi-pdf-mobile-tip {
	position: absolute;
	inset: 0;
	display: flex;
	flex-direction: column;
	align-items: center;
	justify-content: flex-start;
	padding: 18% 32px 32px;
	text-align: center;
	box-sizing: border-box;
	background: #f5f5f5;
}

.xuexi-pdf-mobile-tip[hidden] {
	display: none !important;
}

.xuexi-pdf-mobile-tip__box {
	width: 100%;
	max-width: 480px;
	padding: 36px 28px 32px;
	background: #fff;
	border: 2px solid #e60115;
	border-radius: 12px;
	box-shadow: 0 8px 28px rgba(230, 1, 21, 0.18);
}

.xuexi-pdf-mobile-tip__title {
	margin: 0 0 14px;
	color: #e60115;
	font-size: 22px;
	font-weight: bold;
	line-height: 1.4;
}

.xuexi-pdf-mobile-tip__desc {
	margin: 0 0 28px;
	color: #333;
	font-size: 17px;
	line-height: 1.7;
}

.xuexi-pdf-open-btn {
	display: inline-block;
	padding: 16px 56px;
	background: #e60115;
	color: #fff;
	text-decoration: none;
	border-radius: 8px;
	font-size: 20px;
	font-weight: bold;
	box-shadow: 0 4px 14px rgba(230, 1, 21, 0.35);
	letter-spacing: 1px;
}

.xuexi-pdf-open-btn:hover {
	background: #c40012;
	color: #fff;
}

@media screen and (max-width: 991px) {
	.xuexi-grid {
		grid-template-columns: repeat(2, 1fr);
		gap: 14px;
	}
}

@media screen and (max-width: 520px) {
	.xuexi-grid {
		grid-template-columns: 1fr;
	}

	.xuexi-modal-inner {
		height: 95vh;
	}
}