.course {
	padding: 13px 0 30px;
	background: #f5f7fa;
}

.course-wrap {
	max-width: 1200px;
	margin: 0 auto;
}

.course-hd {
	margin-bottom: 32px;
}

.course-sort {
    max-width: 1200px;
	display: flex;
	align-items: center;
	justify-content: space-between;
	flex-wrap: wrap;
	gap: 12px 20px;
	min-height: 48px;
	padding: 14px 22px;
	box-sizing: border-box;
	background: #f0f4f8;
	border: 1px solid #d1d9e0;
	border-radius: 8px;
}

.course-sort-l {
	display: flex;
	align-items: center;
	flex-wrap: wrap;
	gap: 8px 32px;
}

.course-sort-label {
	font-size: 15px;
	color: #4a5568;
	font-weight: 400;
	white-space: nowrap;
}

.course-sort-btn {
	margin: 0;
	padding: 0;
	border: none;
	background: transparent;
	font-size: 15px;
	line-height: 1.4;
	color: #4a5568;
	cursor: pointer;
	display: inline-flex;
	align-items: center;
	gap: 6px;
	font-family: inherit;
	white-space: nowrap;
	transition: color 0.2s;
}

.course-sort-btn:hover {
	color: #1890ff;
}

.course-sort-btn.active {
	color: #1890ff;
	font-weight: 500;
}


.course-total {
	font-size: 15px;
	color: #4a5568;
	flex-shrink: 0;
}

.course-total em {
	font-style: normal;
	color: #1890ff;
	font-weight: 600;
}

@media (max-width: 640px) {
	.course-sort {
		flex-direction: column;
		align-items: stretch;
	}
	.course-total {
		text-align: right;
		margin-left: 0;
	}
}

.course-list {
	display: grid;
	grid-template-columns: repeat(4, 275px);
	gap: 22px 32px;
	justify-content: space-between;
}

.course-item {
	width: 275px;
	height: 310px;
	background: #fff;
	border-radius: 12px;
	overflow: hidden;
	box-shadow: 0 2px 12px rgba(0, 0, 0, 0.08);
	transition: all 0.3s;
}

.course-item:hover {
	transform: translateY(-4px);
	box-shadow: 0 8px 20px rgba(0, 0, 0, 0.12);
}

.course-link {
	display: block;
	width: 100%;
	height: 100%;
	text-decoration: none;
	color: inherit;
}

.course-thumb {
	position: relative;
	width: 100%;
	height: 160px;
	overflow: hidden;
	background: #f0f0f0;
}

.course-thumb img {
	width: 100%;
	height: 100%;
	object-fit: cover;
	transition: transform 0.3s;
}

.course-item:hover .course-thumb img {
	transform: scale(1.05);
}

.course-duration {
	position: absolute;
	bottom: 8px;
	left: 16px;
	padding: 4px 10px;
	background: #9D9B9E;
	color: #000;
	font-size: 12px;
	border-radius: 12px;
}

.course-info {
	padding: 16px;
	display: flex;
	flex-direction: column;
	height: 145px;
	box-sizing: border-box;
}

.course-title {
	font-size: 16px;
	font-weight: 600;
	color: #333;
	line-height: 1.5;
	margin: 0 0 auto 0;
	overflow: hidden;
	text-overflow: ellipsis;
	display: -webkit-box;
	-webkit-line-clamp: 1;
	-webkit-box-orient: vertical;
}

.course-cate {
	font-size: 14px;
	color: #666;
	overflow: hidden;
	text-overflow: ellipsis;
	display: -webkit-box;
	-webkit-line-clamp: 1;
	-webkit-box-orient: vertical;
}

.course-bot {
	display: flex;
	align-items: center;
	justify-content: space-between;
	gap: 12px;
	font-size: 14px;
	color: #666;
	padding-top: 8px;
	min-width: 0;
}

.course-teacher {
	flex: 1 1 0;
	min-width: 0;
	overflow: hidden;
	text-overflow: ellipsis;
	white-space: nowrap;
}

.course-teacher .iconfont {
	vertical-align: middle;
	margin-right: 6px;
}

.course-views {
	display: flex;
	align-items: center;
	gap: 6px;
	flex-shrink: 0;
	white-space: nowrap;
}

.icon-maikefeng {
	font-size: 20px;
	color: #3A83FE
}

.icon-weibiaoti2fuzhi12 {
	font-size: 20px;
	color: #FF9A00
}

.course-views img {
	width: 16px;
	height: 16px;
	flex-shrink: 0;
}

.course-sort-icon {
	width: 8px;
	height: 4px;
}

@media (max-width: 1200px) {
	.course-list {
		grid-template-columns: repeat(3, 275px);
		justify-content: center;
	}
}

@media (max-width: 900px) {
	.course-list {
		grid-template-columns: repeat(2, 275px);
	}
}

@media (max-width: 600px) {
	.course-list {
		grid-template-columns: 1fr;
		max-width: 350px;
		margin: 0 auto;
	}
	
	.course-item {
		width: 100%;
	}
}

.topic {
	padding: 0 0 25px;
	background: #f5f7fa;
}

.topic-in {
	max-width: 1200px;
	margin: 0 auto;
	padding: 0 0 0;
	box-sizing: border-box;
}

.topic-hd {
	display: flex;
	align-items: center;
	gap: 10px;
	margin-bottom: 17px;
}

.topic-hd-title {
	margin: 0;
	font-size: 26px;
	font-weight: 600;
	color: #333;
	line-height: 1.3;
	flex-shrink: 0;
}

.topic-hd-icon {
	display: block;
	flex-shrink: 0;
	width: 20px;
	height: 13px;
	object-fit: contain;
}

.topic-hd-line {
	flex: 1;
	height: 1px;
	background: #c5d9eb;
	min-width: 20px;
}

.topic-more {
	flex-shrink: 0;
	font-size: 15px;
	color: #4a5568;
	text-decoration: none;
}

.topic-more:hover {
	color: #1890ff;
}

.topic-body {
	display: flex;
	align-items: stretch;
	gap: 24px;
}

.topic-thumb {
	flex: 0 0 615px;
	width: 615px;
	height: 335px;
	border-radius: 10px;
	overflow: hidden;
	background: #e8ecf1;
	box-shadow: 0 2px 12px rgba(0, 0, 0, 0.06);
}

.topic-thumb a {
	display: block;
	width: 100%;
	height: 100%;
	text-decoration: none;
}

.topic-img {
    width: 615px;
    height: 335px;
    object-fit: cover;
    display: block;
    position: relative;
}

.topic-img :hover {
	transform: translateY(-5px);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
}

.topic-img.slide-out {
    transform: translateX(-30px);
    opacity: 0;
}

.topic-img.slide-in {
    transform: translateX(30px);
    animation: slideIn 0.5s ease forwards;
}

.friend_link {
	padding: 0 0 30px;
    background: #f5f7fa;
}

.friend-link-inner {
	max-width: 1200px;
    margin: 0 auto;
    padding: 0 0 0;
    box-sizing: border-box;
    display: flex;
    justify-content: flex-start;
    gap: 100px;
    margin-top: 20px;
    flex-wrap: wrap;
}

.friend-link-img {
    width: 330px;
    height: 80px;
    object-fit: cover;
    display: block;
    transition: transform 0.3s ease, opacity 0.3s ease;
	border-radius: 6px;
}

.friend-link-img:hover {
    transform: translateY(-5px);
    opacity: 0.9;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
}

@keyframes slideIn {
    from {
        transform: translateX(30px);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

.topic-list-wrap {
	flex: 1;
	min-width: 0;
	border-radius: 10px;
	padding: 8px 0;
	box-sizing: border-box;
}

.topic-list {
	margin: 0;
	padding: 0;
	list-style: none;
}

.topic-li {
	margin: 0;
	padding: 0;
}

.topic-item {
	display: flex;
	align-items: center;
	gap: 10px;
	padding: 10px 18px;
	text-decoration: none;
	color: #333;
	font-size: 15px;
	line-height: 1.45;
	box-sizing: border-box;
}

.topic-item:hover {
	background: rgba(255, 255, 255, 0.85);
	color: #1890ff;
}

.topic-icon {
	flex-shrink: 0;
	width: 16px;
	display: flex;
	align-items: center;
	justify-content: center;
}

.topic-icon img {
	display: block;
	width: 4px;
	height: 4px;
}

.topic-name {
	flex: 1;
	min-width: 0;
	overflow: hidden;
	text-overflow: ellipsis;
	white-space: nowrap;
}

.topic-date {
	flex-shrink: 0;
	font-size: 13px;
	color: #888;
	margin-left: 8px;
}

.topic-item:hover .topic-date {
	color: #888;
}

@media (max-width: 1200px) {
	.topic-in {
		padding: 0 16px;
	}

	.topic-body {
		flex-direction: column;
		align-items: stretch;
	}

	.topic-thumb {
		flex: none;
		width: 100%;
		height: auto;
	}

	.topic-img {
		width: 100%;
		height: auto;
		aspect-ratio: 615 / 335;
	}

	.topic-list-wrap {
		width: 100%;
	}
}