/* 课程详情页布局 */
        .course-detail-container {
            display: flex;
            gap: 30px;
            margin-bottom: 60px;
        }
        
        .course-main-content {
            flex: 3;
            background: var(--white);
            border-radius: var(--border-radius);
            box-shadow: var(--box-shadow);
            overflow: hidden;
        }
        
        .course-sidebar {
            flex: 1;
            display: flex;
            flex-direction: column;
            gap: 30px;
        }
        
        /* 视频播放区域 */
        .video-container {
            position: relative;
            padding-top: 56.25%; /* 16:9 Aspect Ratio */
            background: #000;
        }
        
        .video-player {
            position: absolute;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            border: none;
        }
        
        /* 课程信息 */
        .course-info {
            padding: 25px;
        }
        
        .course-header {
            display: flex;
            justify-content: space-between;
            align-items: center;
            margin-bottom: 20px;
        }
        
        .course-title {
            font-size: 1.8rem;
            color: var(--dark);
            margin-bottom: 10px;
        }
        
        .course-meta {
            display: flex;
            gap: 15px;
            color: var(--text-light);
            font-size: 0.95rem;
            margin-bottom: 20px;
        }
        
        .course-meta span {
            display: flex;
            align-items: center;
            gap: 5px;
        }
        
        .course-category-tag {
            display: inline-block;
            background: rgba(46, 125, 50, 0.1);
            color: var(--primary);
            padding: 5px 15px;
            border-radius: 20px;
            font-size: 0.85rem;
            margin-bottom: 15px;
        }
        
        .course-desc {
            color: var(--text);
            line-height: 1.8;
            margin-bottom: 25px;
        }
        
        .course-actions {
            display: flex;
            gap: 15px;
            margin-top: 20px;
        }
        
        .btn {
            display: inline-block;
            background: var(--accent);
            color: white;
            padding: 10px 25px;
            border-radius: 25px;
            text-decoration: none;
            font-weight: 500;
            font-size: 1.1rem;
            transition: all 0.3s;
            box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
            margin: 10px 0;
            border: none;
            cursor: pointer;
        }
        
        .btn-primary {
            background: var(--primary);
        }
        
        .btn:hover {
            transform: translateY(-2px);
            box-shadow: 0 8px 20px rgba(0,0,0,0.2);
        }
        
        /* 课程章节列表 */
        .course-playlist {
            background: var(--white);
            border-radius: var(--border-radius);
            box-shadow: var(--box-shadow);
            overflow: hidden;
        }
        
        .playlist-header {
            background: var(--primary);
            color: var(--white);
            padding: 15px 20px;
            font-size: 1.2rem;
            font-weight: 500;
        }
        
        .playlist-items {
            max-height: 500px;
            overflow-y: auto;
        }
        
        .playlist-item {
            padding: 15px 20px;
            border-bottom: 1px solid var(--light-gray);
            cursor: pointer;
            transition: background 0.3s;
            display: flex;
            align-items: center;
        }
        
        .playlist-item:hover {
            background: rgba(46, 125, 50, 0.05);
        }
        
        .playlist-item.active {
            background: rgba(46, 125, 50, 0.1);
            border-left: 3px solid var(--primary);
        }
        
        .playlist-item .item-index {
            display: flex;
            align-items: center;
            justify-content: center;
            width: 28px;
            height: 28px;
            background: rgba(46, 125, 50, 0.1);
            color: var(--primary);
            border-radius: 50%;
            margin-right: 15px;
            font-size: 0.9rem;
        }
        
        .playlist-item.active .item-index {
            background: var(--primary);
            color: var(--white);
        }
        
        .playlist-item .item-title {
            flex: 1;
            font-weight: 500;
        }
        
        .playlist-item .item-duration {
            color: var(--text-light);
            font-size: 0.9rem;
        }
        
        /* 讲师卡片 */
        .instructor-card {
            background: var(--white);
            border-radius: var(--border-radius);
            box-shadow: var(--box-shadow);
            overflow: hidden;
            padding: 25px;
            text-align: center;
        }
        
        .instructor-avatar {
            width: 120px;
            height: 120px;
            border-radius: 50%;
            object-fit: cover;
            margin: 0 auto 20px;
            border: 3px solid var(--primary);
        }
        
        .instructor-name {
            font-size: 1.5rem;
            margin-bottom: 10px;
        }
        
        .instructor-title {
            color: var(--primary);
            margin-bottom: 15px;
            font-weight: 500;
        }
        
        .instructor-bio {
            color: var(--text);
            line-height: 1.7;
            margin-bottom: 20px;
        }
        
        .social-links {
            display: flex;
            justify-content: center;
            gap: 12px;
        }
        
        .social-links a {
            display: flex;
            align-items: center;
            justify-content: center;
            width: 36px;
            height: 36px;
            background: var(--light);
            border-radius: 50%;
            color: var(--primary);
            transition: all 0.3s;
        }
        
        .social-links a:hover {
            background: var(--primary);
            color: var(--white);
        }
        
        /* 课程详情标签页 */
        .course-tabs {
            display: flex;
            border-bottom: 1px solid var(--light-gray);
            margin-bottom: 25px;
        }
        
        .course-tab {
            padding: 12px 25px;
            cursor: pointer;
            font-weight: 500;
            color: var(--gray);
            transition: all 0.3s;
            position: relative;
        }
        
        .course-tab.active {
            color: var(--primary);
        }
        
        .course-tab.active::after {
            content: '';
            position: absolute;
            bottom: -1px;
            left: 0;
            width: 100%;
            height: 3px;
            background: var(--primary);
        }
        
        .tab-content {
            padding: 0 20px 20px;
            display: none;
        }
        
        .tab-content.active {
            display: block;
        }
        
        .tab-content h3 {
            font-size: 1.4rem;
            margin-bottom: 20px;
            color: var(--dark);
        }
        
        .tab-content p {
            color: var(--text);
            line-height: 1.8;
            margin-bottom: 15px;
        }
        
        .tab-content ul {
            padding-left: 20px;
            margin-bottom: 25px;
        }
        
        .tab-content li {
            margin-bottom: 10px;
            color: var(--text);
            line-height: 1.6;
        }
        
        /* 相关课程 */
        .related-courses-grid {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
            gap: 25px;
            margin-top: 30px;
        }
        
        .related-course-card {
            background: var(--white);
            border-radius: var(--border-radius);
            box-shadow: var(--box-shadow);
            overflow: hidden;
            transition: var(--transition);
			text-decoration: none;
        }
        
        .related-course-card:hover {
            transform: translateY(-5px);
            box-shadow: 0 15px 30px rgba(0,0,0,0.15);
        }
        
        .related-course-image {
            height: 160px;
            overflow: hidden;
        }
        
        .related-course-image img {
            width: 100%;
            height: 100%;
            object-fit: cover;
            transition: transform 0.5s ease;
        }
        
        .related-course-card:hover .related-course-image img {
            transform: scale(1.05);
        }
        
        .related-course-content {
            padding: 20px;
			color: var(--text);
        }
        
        .related-course-title {
            font-size: 1.2rem;
            margin-bottom: 10px;
            color: var(--dark);
        }
        
        .related-course-meta {
            display: flex;
            justify-content: space-between;
            color: var(--text-light);
            font-size: 0.9rem;
            margin-top: 15px;
        }
		
        
        /* 移动端搜索弹窗优化 */
        @media (max-width: 768px) {
            /* 在线客服弹窗优化 */
            .service-option.hotline-option {
                display: none;
            }
            
            .mobile-contact-info {
                display: block;
            }
            
            /* 搜索弹窗宽度优化 */
            .search-modal .modal {
                max-width: 90%;
            }
            
            .search-modal input {
                padding: 12px 15px;
                font-size: 1rem;
            }
            
            .search-modal .search-button {
                padding: 0 20px;
            }
            
            .search-tags {
                gap: 8px;
            }
            
            .search-tag {
                padding: 6px 12px;
                font-size: 0.8rem;
            }
            
            /* 课程详情页响应式 */
            .course-detail-container {
                flex-direction: column;
            }
            
            .course-sidebar {
                flex-direction: row;
                flex-wrap: wrap;
            }
            
            .course-playlist {
                flex: 1;
                min-width: 100%;
            }
            
            .instructor-card {
                flex: 1;
                min-width: 300px;
            }
            
            .course-header {
                flex-direction: column;
                align-items: flex-start;
                gap: 15px;
            }
            
            .course-actions {
                width: 100%;
                flex-direction: column;
            }
            
            .course-sidebar {
                flex-direction: column;
            }
            
            .instructor-card {
                min-width: 100%;
            }
        }
        
        
        @media (max-width: 768px) {
            /* 根据移动端导航栏实际高度调整 */
            body {
                padding-top: 60px;
            }
            .nav-links {
                display: none;
            }
            
            .hamburger {
                display: block;
            }
            
            .nav-icons {
                display: flex;
                gap: 5px;
            }
            
            .logo {
                position: absolute;
                left: 50%;
                transform: translateX(-50%);
            }
            
            .logo img {
                height: 44px;
            }
            
            .mobile-icons-row {
                display: flex;
            }
            
            .mobile-nav {
                display: block;
            }
            
            .section {
                padding: 40px 15px;
            }
            
            .section-title {
                margin-bottom: 30px;
            }
            
            .section-title h2 {
                font-size: 2rem;
            }
            
            .modal {
                width: 95%;
            }
            
            /* 移动端隐藏地球图标 */
            .region-selector i {
                display: none;
            }

            /* 移动端底部调整 */
            .footer-top-row {
                flex-direction: column;
                align-items: center;
            }
            
            .footer-extra-links {
                flex-direction: row;
                align-items: center;
                gap: 3px;
                font-size: clamp(12px, 3vw, 0.95rem);
            }
            
            .footer-extra-links a::after {
                display: none;
            }
            
            /* 调整按钮位置 */
            .customer-service {
                bottom: 65px;
                right: 20px;
            }
            
            .back-to-top {
                bottom: 20px;
                right: 20px;
            }
            
            /* 页面横幅响应式调整 */
            .page-banner {
                height: 250px;
            }
            
            .page-banner h1 {
                font-size: 2.2rem;
            }
            
            .page-banner p {
                font-size: 1rem;
            }
            
            .page-banner {
                height: 200px;
            }
            
            .course-title {
                font-size: 1.5rem;
            }
            
            .course-meta {
                flex-wrap: wrap;
            }
            
            .playlist-item {
                padding: 12px 15px;
            }
            
            .tabs {
                overflow-x: auto;
                flex-wrap: nowrap;
                padding: 0 10px;
            }
   
            /* 单列布局 */
                .language-list {
                grid-template-columns: 1fr;
            }
  
            /* 调整语言项高度 */
                .language-item {
                padding: 8px 12px;
                height: auto;
            }
  
            /* 减少弹窗内边距 */
                .modal {
                max-height: 85vh;
            }
  
           .modal-content {
                padding: 10px;
            }
            .course-tab {
                font-size: 0.8rem;
                padding: 12px 15px;
            }
       }
        
        @media (max-width: 576px) {
            /* 根据移动端导航栏实际高度调整 */
            body {
                padding-top: 60px;
            }
            .navbar {
                padding: 15px 10px;
            }
            
            .logo img {
                height: 40px;
            }
            
            .back-to-top, .customer-service {
                width: 40px;
                height: 40px;
                font-size: 1.2rem;
            }
            
            .customer-service {
                bottom: 60px;
            }
            
            .section {
                padding: 35px 12px;
            }
            
            .section-title h2 {
                font-size: 1.8rem;
            }
            
            .tabs {
                overflow-x: auto;
                flex-wrap: nowrap;
                padding: 0 10px;
            }
            
            .tab {
                padding: 10px 8px;
                font-size: 0.9rem;
                white-space: nowrap;
            }
            
            /* 移动端地区选择器 */
            .region-selector {
                font-size: 0.9rem;
                padding: 3px 6px;
            }

            /* 社交分享弹窗响应式 */
            .social-qr-container {
                gap: 15px;
            }
            
            .social-qr-item {
                flex: 0 0 140px;
            }
            
            .social-qr-image {
                width: 120px;
                height: 120px;
            }
            
            /* 页面横幅响应式调整 */
            .page-banner {
                height: 200px;
            }
            
            .page-banner h1 {
                font-size: 1.8rem;
            }
        }
        
        /* 超小屏幕下进一步缩小按钮 */
        @media (max-width: 400px) {
            /* 根据移动端导航栏实际高度调整 */
            body {
                padding-top: 60px;
            }
            .back-to-top, .customer-service {
                width: 32px;
                height: 32px;
                font-size: 0.8rem;
                bottom: 15px;
                right: 10px;
            }
            
            .customer-service {
                bottom: 47px;
            }
            
            .region-selector {
                font-size: 0.7rem;
                padding: 3px 6px;
            }
            .language-item {
                font-size: 0.85rem;
            }
  
            .language-flag {
                width: 25px;
                height: 18px;
            }
  
            .tabs .tab {
                padding: 8px 10px;
                font-size: 0.85rem;
            }
        }
        
        /* 客服弹窗优化 - 电脑端布局 */
        @media (min-width: 769px) {
            .service-options {
                flex-direction: row;
                flex-wrap: nowrap;
            }
            
            .service-option {
                min-width: auto;
                margin-bottom: 0;
                height: 220px;
            }
            
            .service-option.combined-option {
                flex-direction: column;
            }
            
            .service-option.combined-option .hotline-part,
            .service-option.combined-option .message-part {
                flex: 1;
                padding: 15px;
            }
            
            .service-option.combined-option .hotline-part {
                border-right: none;
                border-bottom: 1px solid #eee;
            }
        }