/* LinkedKeeper Course Detail Page - Enhanced Course Content Display */

/* QCon-inspired Typography */
:root {
    --font-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    --font-secondary: 'Source Sans Pro', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    --font-weight-light: 300;
    --font-weight-normal: 400;
    --font-weight-medium: 500;
    --font-weight-semibold: 600;
    --font-weight-bold: 700;
    --font-weight-extrabold: 800;
}

/* Apply QCon-style typography to body and main elements */
body {
    font-family: var(--font-primary);
    font-weight: var(--font-weight-normal);
    line-height: 1.6;
    color: #374151;
}

/* Course Detail Page Layout */
.course-detail-page {
    background: white;
    min-height: 100vh;
}

/* Course Hero Section */
.course-hero {
    background: linear-gradient(135deg, #1e293b 0%, #334155 100%);
    color: white;
    padding: 80px 0;
    position: relative;
    overflow: hidden;
}

.course-hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><defs><pattern id="heroPattern" width="20" height="20" patternUnits="userSpaceOnUse"><path d="M 20 0 L 0 0 0 20" fill="none" stroke="%23ffffff" stroke-width="0.1" opacity="0.3"/></pattern></defs><rect width="100" height="100" fill="url(%23heroPattern)"/></svg>');
    opacity: 0.1;
    z-index: 0;
}

.course-hero .container {
    position: relative;
    z-index: 1;
}

.course-breadcrumb {
    margin-bottom: 2rem;
    font-size: 0.9rem;
    opacity: 0.8;
}

.course-breadcrumb a {
    color: #cbd5e1;
    text-decoration: none;
    transition: color 0.3s ease;
}

.course-breadcrumb a:hover {
    color: white;
}

.course-breadcrumb span {
    margin: 0 0.5rem;
    color: #94a3b8;
}

.course-header {
    max-width: 800px;
}

.course-meta {
    display: flex;
    gap: 1rem;
    margin-bottom: 1.5rem;
    flex-wrap: wrap;
}

.course-category,
.course-level,
.course-duration {
    background: rgba(255, 255, 255, 0.1);
    padding: 0.5rem 1rem;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 500;
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.course-title {
    font-family: var(--font-primary);
    font-size: 3rem;
    font-weight: var(--font-weight-bold);
    line-height: 1.2;
    margin-bottom: 1.5rem;
    letter-spacing: -0.02em;
    color: #111827;
    word-wrap: break-word;
    overflow-wrap: break-word;
    hyphens: auto;
    -webkit-hyphens: auto;
    -ms-hyphens: auto;
    text-align: left;
}

.course-subtitle {
    font-family: var(--font-secondary);
    font-size: 1.25rem;
    font-weight: var(--font-weight-normal);
    line-height: 1.6;
    opacity: 0.9;
    margin-bottom: 2rem;
    color: #6b7280;
}

.course-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
    gap: 1rem;
    margin-top: 1.5rem;
}

.stat-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    background: rgba(255, 255, 255, 0.05);
    padding: 1rem;
    border-radius: 12px;
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.1);
    transition: all 0.3s ease;
}

.stat-item:hover {
    background: rgba(255, 255, 255, 0.1);
    transform: translateY(-2px);
}

.stat-icon {
    font-size: 1.5rem;
    opacity: 0.8;
}

.stat-content {
    display: flex;
    flex-direction: column;
}

.stat-number {
    font-size: 1.25rem;
    font-weight: 700;
    color: #60a5fa;
}

.stat-label {
    font-size: 0.8rem;
    opacity: 0.8;
}

/* Course Content Section */
.course-content {
    padding: 40px 0 80px 0;
    background: white;
}

.content-layout {
    display: grid;
    grid-template-columns: 1fr 360px; /* Main content, Sidebar */
    gap: 2rem;
    max-width: 1400px;
    margin: 0 auto;
    padding: 0;
    align-items: start;
    position: relative;
}

/* Left Vertical Tab Navigation */
.content-left-tabs {
    position: fixed;
    left: max(20px, calc((100vw - 1400px) / 2 + 20px)); /* Responsive positioning: 20px margin or centered with 20px offset */
    top: 9rem; /* Adjusted to align with title and payment sections */
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    padding: 1rem 0.5rem;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(226, 232, 240, 0.8);
    border-radius: 16px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
    width: 60px;
    align-items: center;
    justify-content: flex-start;
    z-index: 1000;
    transition: all 0.3s ease;
}

.content-left-tabs:hover {
    background: rgba(255, 255, 255, 0.98);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.15);
    transform: translateY(-2px);
}

.left-tab-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 45px;
    height: 45px;
    border: none;
    background: transparent;
    border-radius: 12px;
    cursor: pointer;
    transition: all 0.3s ease;
    position: relative;
    margin: 0;
}

.left-tab-btn:hover {
    background: rgba(59, 130, 246, 0.1);
    transform: translateY(-1px);
}

.left-tab-btn.active {
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.15), rgba(37, 99, 235, 0.1));
    box-shadow: 0 2px 8px rgba(59, 130, 246, 0.2);
}

.left-tab-btn.active::before {
    content: '';
    position: absolute;
    left: -12px;
    top: 50%;
    transform: translateY(-50%);
    width: 4px;
    height: 24px;
    background: linear-gradient(180deg, #3b82f6, #1d4ed8);
    border-radius: 0 2px 2px 0;
    box-shadow: 0 0 8px rgba(59, 130, 246, 0.4);
}

.left-tab-icon {
    font-size: 1.3rem;
    line-height: 1;
    font-weight: 400;
    color: #6b7280;
    transition: color 0.3s ease;
}

.left-tab-icon.dollar-icon {
    font-size: 1rem;
    font-weight: 300;
}

.left-tab-btn:hover .left-tab-icon {
    color: #3b82f6;
}

.left-tab-btn.active .left-tab-icon {
    color: #1d4ed8;
}

/* Action Buttons (Like and Comment) */
.action-buttons {
    display: flex;
    gap: 1rem;
    margin: 1.5rem 0;
    align-items: center;
}

.action-btn {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    background: #f8fafc;
    border: 1px solid #e5e7eb;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
    font-size: 0.875rem;
    color: #6b7280;
    font-weight: 500;
}

.action-btn:hover {
    background: #f1f5f9;
    border-color: #cbd5e1;
    color: #3b82f6;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.action-btn svg {
    transition: all 0.3s ease;
}

.action-btn:hover svg {
    fill: #3b82f6;
    transform: scale(1.1);
}

.like-btn.liked svg {
    fill: #ef4444;
}

.like-btn.liked {
    color: #ef4444;
    border-color: #fecaca;
    background: #fef2f2;
}

.action-count {
    font-weight: 600;
}

/* Responsive styles for action buttons */
@media (max-width: 768px) {
    .action-buttons {
        gap: 0.75rem;
        margin: 1rem 0;
    }
    
    .action-btn {
        padding: 0.4rem 0.75rem;
        font-size: 0.8rem;
    }
    
    .action-btn svg {
        width: 18px;
        height: 18px;
    }
}

.content-main {
    min-width: 0;
    padding-top: 0.5rem; /* Align with left tabs top padding */
    overflow: visible; /* Ensure content is not clipped */
}

.content-section {
    margin-bottom: 2.5rem;
    overflow: visible; /* Ensure content is not clipped */
}

/* Course Content Wrapper - Handle large content */
.course-content-wrapper {
    width: 100%;
    max-width: 100%;
    overflow-x: auto; /* Allow horizontal scrolling for wide content */
    overflow-y: visible; /* Allow vertical expansion */
    word-wrap: break-word;
    overflow-wrap: break-word;
    position: relative;
    /* Custom scrollbar styling for better UX */
    scrollbar-width: thin;
    scrollbar-color: #cbd5e1 #f1f5f9;
}

/* Webkit scrollbar styling for course content wrapper */
.course-content-wrapper::-webkit-scrollbar {
    height: 8px;
    width: 8px;
}

.course-content-wrapper::-webkit-scrollbar-track {
    background: #f1f5f9;
    border-radius: 4px;
}

.course-content-wrapper::-webkit-scrollbar-thumb {
    background: #cbd5e1;
    border-radius: 4px;
    transition: background 0.2s ease;
}

.course-content-wrapper::-webkit-scrollbar-thumb:hover {
    background: #94a3b8;
}

.content-section h2 {
    font-family: var(--font-primary);
    font-size: 2rem;
    font-weight: var(--font-weight-bold);
    color: #111827;
    margin-bottom: 2rem;
    position: relative;
    padding-bottom: 1rem;
    letter-spacing: -0.01em;
}

.content-section h2::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 60px;
    height: 4px;
    background: linear-gradient(90deg, #3b82f6, #8b5cf6);
    border-radius: 2px;
}

/* Course description content styling - improved spacing and alignment */
.content-section p,
.course-content-wrapper p {
    margin: 1.5rem 0;
    line-height: 1.7;
    color: #374151;
    font-size: 1rem;
    word-wrap: break-word;
    overflow-wrap: break-word;
}

.content-section h3 {
    margin: 2.5rem 0 1.5rem 0;
    font-family: var(--font-primary);
    font-size: 1.5rem;
    font-weight: var(--font-weight-semibold);
    color: #111827;
    line-height: 1.4;
    /* Add scroll margin to compensate for fixed header */
    scroll-margin-top: 100px;
}

.content-section ul {
    margin: 1.5rem 0;
    padding-left: 1.5rem;
}

.content-section ol {
    margin: 1.5rem 0;
    padding-left: 1.5rem;
}

.content-section li {
    margin-bottom: 0.5rem;
    margin-top: 0.5rem;
    line-height: 1.7;
    color: #374151;
    font-size: 1rem;
}

.content-section li:first-child {
    margin-top: 0;
}

.content-section li:last-child {
    margin-bottom: 0;
}

.content-section li strong {
    color: #111827;
    font-weight: var(--font-weight-semibold);
    margin-right: 0.25rem;
}

/* Remove extra spacing from paragraphs inside list items */
.content-section li > p {
    margin-top: 0;
    margin-bottom: 0;
}

.content-section li > p:first-child {
    margin-top: 0.25rem;
}

.content-section li > p:last-child {
    margin-bottom: 0.25rem;
}

/* Markdown content styling for better display */
.content-section img,
.course-content-wrapper img {
    max-width: 100%;
    height: auto;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    margin: 1.5rem 0;
    display: block;
    width: auto; /* Allow natural width, but respect max-width */
}

.content-section table,
.course-content-wrapper table {
    width: 100%;
    max-width: 100%;
    border-collapse: collapse;
    margin: 1.5rem 0;
    background: white;
    border-radius: 8px;
    overflow: visible; /* Changed from hidden to visible */
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    display: table; /* Ensure table layout */
    table-layout: auto; /* Allow table to expand naturally */
}

/* If table is too wide, allow horizontal scrolling within wrapper */
.course-content-wrapper > table {
    display: table;
    width: auto;
    min-width: 100%;
}

.content-section th,
.content-section td {
    padding: 0.75rem 1rem;
    text-align: left;
    border-bottom: 1px solid #e5e7eb;
}

.content-section th {
    background: #f8fafc;
    font-weight: var(--font-weight-semibold);
    color: #374151;
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.content-section td {
    color: #374151;
    font-size: 0.95rem;
}

.content-section tr:hover {
    background: #f8fafc;
}

.content-section blockquote {
    border-left: 4px solid #3b82f6;
    background: #f8fafc;
    padding: 1rem 1.5rem;
    margin: 1.5rem 0;
    border-radius: 0 8px 8px 0;
    font-style: italic;
    color: #4b5563;
}

.content-section code {
    background: #f1f5f9;
    padding: 0.2rem 0.4rem;
    border-radius: 4px;
    font-family: 'Monaco', 'Menlo', 'Ubuntu Mono', monospace;
    font-size: 0.9em;
    color: #e11d48;
}

.content-section pre,
.course-content-wrapper pre {
    background: #1e293b;
    color: #e2e8f0;
    padding: 1.5rem;
    border-radius: 8px;
    overflow-x: auto;
    overflow-y: visible; /* Allow vertical expansion for long code */
    margin: 1.5rem 0;
    font-family: 'Monaco', 'Menlo', 'Ubuntu Mono', monospace;
    font-size: 0.9rem;
    line-height: 1.5;
    max-width: 100%;
    white-space: pre;
    word-wrap: normal;
}

/* Ensure code blocks don't break layout */
.course-content-wrapper pre code {
    display: block;
    white-space: pre;
    overflow-x: auto;
}

.content-section pre code {
    background: none;
    padding: 0;
    color: inherit;
    font-size: inherit;
}

.content-section h1,
.content-section h2,
.content-section h4,
.content-section h5,
.content-section h6 {
    margin: 2rem 0 1rem 0;
    font-family: var(--font-primary);
    color: #111827;
    line-height: 1.3;
    word-wrap: break-word;
    overflow-wrap: break-word;
    hyphens: auto;
    -webkit-hyphens: auto;
    -ms-hyphens: auto;
    text-align: left;
    /* Add scroll margin to compensate for fixed header */
    scroll-margin-top: 100px;
}

.content-section h1 {
    font-size: 2rem;
    font-weight: var(--font-weight-bold);
    border-bottom: 2px solid #e5e7eb;
    padding-bottom: 0.5rem;
    line-height: 1.25;
    margin-top: 2rem; /* 恢复原有的上间距 */
}

.content-section h2 {
    font-size: 1.75rem;
    font-weight: var(--font-weight-bold);
    line-height: 1.3;
}

.content-section h4 {
    font-size: 1.25rem;
    font-weight: var(--font-weight-semibold);
    line-height: 1.35;
}

.content-section h5 {
    font-size: 1.1rem;
    font-weight: var(--font-weight-semibold);
    line-height: 1.4;
}

.content-section h6 {
    font-size: 1rem;
    font-weight: var(--font-weight-semibold);
    color: #6b7280;
    line-height: 1.4;
}

/* Content Types Display */
.content-types {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-bottom: 3rem;
}

.content-type-card {
    background: white;
    border: 2px solid #e5e7eb;
    border-radius: 16px;
    padding: 2rem;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.content-type-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, #3b82f6, #8b5cf6);
    transform: scaleX(0);
    transition: transform 0.3s ease;
}

.content-type-card:hover::before {
    transform: scaleX(1);
}

.content-type-card:hover {
    border-color: #3b82f6;
    transform: translateY(-4px);
    box-shadow: 0 12px 30px rgba(59, 130, 246, 0.15);
}

.content-type-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
    display: block;
}

.content-type-title {
    font-size: 1.25rem;
    font-weight: 600;
    color: #1a1a1a;
    margin-bottom: 0.5rem;
}

.content-type-description {
    color: #64748b;
    line-height: 1.6;
    margin-bottom: 1.5rem;
}

.content-type-count {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: #3b82f6;
    font-weight: 500;
    font-size: 0.9rem;
}

/* Course Curriculum styles moved to linkedkeeper-curriculum.css for isolation */

/* Hierarchical Curriculum Styles */
.curriculum-container-isolated {
    background: white;
    border-radius: 16px;
    overflow: hidden;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
    border: 1px solid #e5e7eb;
}

.curriculum-module-isolated {
    border-bottom: 1px solid #f1f5f9;
    transition: all 0.3s ease;
}

.curriculum-module-isolated:last-child {
    border-bottom: none;
}

.curriculum-module-isolated:hover {
    background: #f8fafc;
}

.module-section-header-isolated {
    padding: 1.5rem 2rem;
    background: linear-gradient(135deg, #f8fafc 0%, #f1f5f9 100%);
    border-bottom: 1px solid #e5e7eb;
    cursor: pointer;
    transition: all 0.3s ease;
}

.module-section-header-isolated:hover {
    background: linear-gradient(135deg, #f1f5f9 0%, #e2e8f0 100%);
}

.module-section-header-isolated h3 {
    font-family: var(--font-primary);
    font-size: 1.25rem;
    font-weight: var(--font-weight-semibold);
    color: #111827;
    margin: 0 0 0.5rem 0;
    line-height: 1.4;
}

.module-description {
    font-family: var(--font-secondary);
    font-size: 0.9rem;
    color: #6b7280;
    line-height: 1.5;
    margin: 0;
}

.course-items-isolated {
    padding: 0;
    background: white;
}

.course-item-isolated {
    display: flex;
    align-items: center;
    padding: 1rem 2rem;
    border-bottom: 1px solid #f1f5f9;
    transition: all 0.3s ease;
    position: relative;
}

.course-item-isolated:last-child {
    border-bottom: none;
}

.course-item-isolated:hover {
    background: #f8fafc;
    padding-left: 2.5rem;
}

.course-number-isolated {
    font-family: var(--font-primary);
    font-size: 0.9rem;
    font-weight: var(--font-weight-semibold);
    color: #3b82f6;
    background: #eff6ff;
    padding: 0.5rem 0.75rem;
    border-radius: 8px;
    margin-right: 1rem;
    min-width: 2.5rem;
    text-align: center;
    flex-shrink: 0;
}

.course-title-isolated {
    font-family: var(--font-secondary);
    font-size: 1rem;
    font-weight: var(--font-weight-normal);
    color: #374151;
    line-height: 1.5;
    flex: 1;
    margin-right: 1rem;
}

.course-duration-isolated {
    font-family: var(--font-secondary);
    font-size: 0.85rem;
    font-weight: var(--font-weight-medium);
    color: #6b7280;
    background: #f3f4f6;
    padding: 0.25rem 0.5rem;
    border-radius: 6px;
    flex-shrink: 0;
}

/* Responsive adjustments for hierarchical curriculum */
@media (max-width: 768px) {
    .module-section-header-isolated {
        padding: 1.25rem 1.5rem;
    }
    
    .module-section-header-isolated h3 {
        font-size: 1.1rem;
    }
    
    .module-description {
        font-size: 0.85rem;
    }
    
    .course-item-isolated {
        padding: 0.875rem 1.5rem;
    }
    
    .course-item-isolated:hover {
        padding-left: 1.75rem;
    }
    
    .course-number-isolated {
        font-size: 0.8rem;
        padding: 0.4rem 0.6rem;
        margin-right: 0.75rem;
        min-width: 2.25rem;
    }
    
    .course-title-isolated {
        font-size: 0.9rem;
        margin-right: 0.75rem;
    }
    
    .course-duration-isolated {
        font-size: 0.8rem;
        padding: 0.2rem 0.4rem;
    }
}

@media (max-width: 480px) {
    .module-section-header-isolated {
        padding: 1rem 1.25rem;
    }
    
    .module-section-header-isolated h3 {
        font-size: 1rem;
    }
    
    .module-description {
        font-size: 0.8rem;
    }
    
    .course-item-isolated {
        padding: 0.75rem 1.25rem;
        flex-wrap: wrap;
    }
    
    .course-item-isolated:hover {
        padding-left: 1.5rem;
    }
    
    .course-number-isolated {
        font-size: 0.75rem;
        padding: 0.35rem 0.5rem;
        margin-right: 0.5rem;
        min-width: 2rem;
    }
    
    .course-title-isolated {
        font-size: 0.85rem;
        margin-right: 0.5rem;
        flex: 1;
        min-width: 0;
    }
    
    .course-duration-isolated {
        font-size: 0.75rem;
        padding: 0.15rem 0.35rem;
        margin-top: 0.25rem;
        align-self: flex-start;
    }
}

/* Learning Outcomes */
.outcomes-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.outcome-item {
    background: white;
    border: 2px solid #e5e7eb;
    border-radius: 16px;
    padding: 2rem;
    text-align: center;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.outcome-item::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, #10b981, #059669);
    transform: scaleX(0);
    transition: transform 0.3s ease;
}

.outcome-item:hover::before {
    transform: scaleX(1);
}

.outcome-item:hover {
    border-color: #10b981;
    transform: translateY(-4px);
    box-shadow: 0 12px 30px rgba(16, 185, 129, 0.15);
}

.outcome-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
    display: block;
}

.outcome-item h4 {
    font-size: 1.25rem;
    font-weight: 600;
    color: #1a1a1a;
    margin-bottom: 1rem;
}

.outcome-item p {
    color: #64748b;
    line-height: 1.6;
    margin: 0;
}

/* Student Reviews */
.reviews-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
}

.review-item {
    background: white;
    border: 2px solid #e5e7eb;
    border-radius: 16px;
    padding: 2rem;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.review-item::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, #f59e0b, #d97706);
    transform: scaleX(0);
    transition: transform 0.3s ease;
}

.review-item:hover::before {
    transform: scaleX(1);
}

.review-item:hover {
    border-color: #f59e0b;
    transform: translateY(-4px);
    box-shadow: 0 12px 30px rgba(245, 158, 11, 0.15);
}

.review-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1.5rem;
}

.reviewer-info {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.reviewer-avatar {
    width: 50px;
    height: 50px;
    border-radius: 50%;
    object-fit: cover;
}

.reviewer-details h4 {
    font-size: 1rem;
    font-weight: 600;
    color: #1a1a1a;
    margin: 0 0 0.25rem 0;
}

.reviewer-details span {
    font-size: 0.85rem;
    color: #64748b;
}

.review-rating .stars {
    font-size: 1.25rem;
}

.review-text {
    color: #374151;
    line-height: 1.6;
    margin: 0;
    font-style: italic;
}

/* Sidebar Wrapper Container */
.sidebar-wrapper {
    display: flex;
    flex-direction: row;
    gap: 0;
    position: sticky;
    top: 6rem; /* 增加顶部间距，避免紧贴顶部 */
    background: transparent;
    align-items: flex-start;
    margin-top: 0; /* 确保sidebar从顶部开始 */
    padding-top: 0; /* 移除顶部内边距 */
    height: fit-content;
    max-height: calc(100vh - 8rem); /* 调整最大高度以适应新的top值 */
    overflow-y: auto;
    z-index: 100; /* 确保在其他元素之上 */
}

/* Sidebar */
.content-sidebar {
    flex: 1;
    background: transparent;
    padding-top: 2rem; /* 添加顶部间距，与h1标题对齐 */
    margin-top: 0;
    height: fit-content;
    max-height: calc(100vh - 140px); /* 视口高度减去header和间距 */
    overflow-y: auto;
    /* 自定义滚动条样式 */
    scrollbar-width: thin;
    scrollbar-color: #cbd5e1 #f1f5f9;
    /* 为sidebar-card提供滚动容器 */
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

/* Webkit浏览器滚动条样式 */
.content-sidebar::-webkit-scrollbar {
    width: 8px;
}

.content-sidebar::-webkit-scrollbar-track {
    background: #f1f5f9;
    border-radius: 4px;
}

.content-sidebar::-webkit-scrollbar-thumb {
    background: #cbd5e1;
    border-radius: 4px;
    transition: background 0.2s ease;
}

.content-sidebar::-webkit-scrollbar-thumb:hover {
    background: #94a3b8;
}

/* Sidebar Card滚动条样式 */
.content-sidebar .sidebar-card::-webkit-scrollbar {
    width: 6px;
}

.content-sidebar .sidebar-card::-webkit-scrollbar-track {
    background: #f8fafc;
    border-radius: 3px;
}

.content-sidebar .sidebar-card::-webkit-scrollbar-thumb {
    background: #cbd5e1;
    border-radius: 3px;
    transition: background 0.2s ease;
}

.content-sidebar .sidebar-card::-webkit-scrollbar-thumb:hover {
    background: #94a3b8;
}

/* Tab Content */
.sidebar-tab-content {
    flex: 1;
    position: relative;
    padding-top: 0; /* 移除顶部内边距 */
}

.tab-panel {
    display: none;
    animation: fadeIn 0.3s ease-in-out;
}

.tab-panel.active {
    display: block;
}

/* Content Outline Styles - Improved spacing and isolation */
.content-outline-card {
    background: white !important;
    border: 1px solid #e5e7eb !important;
    border-radius: 12px !important;
    padding: 0 !important; /* 移除所有padding，让内部元素控制间距 */
    position: relative !important;
    overflow: hidden !important;
    transition: all 0.3s ease !important;
    display: flex !important;
    flex-direction: column !important;
    height: auto !important;
    min-height: auto !important;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08) !important;
    margin-bottom: 1.5rem !important; /* 卡片间距 */
}

.content-outline-card:hover {
    transform: translateY(-2px) !important;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1) !important;
    border-color: #cbd5e1 !important;
}

/* Content Outline Header - Improved spacing */
.content-outline-card .course-header {
    padding: 1.5rem 1.5rem 0.75rem 1.5rem !important; /* 统一padding，顶部间距更大 */
    background: white !important;
    border-radius: 12px 12px 0 0 !important; /* 顶部圆角 */
}

.content-outline {
    padding: 0 1.5rem 1.5rem 1.5rem; /* 添加左右和底部padding */
    margin-top: 0; /* 移除顶部margin，因为header已经有底部padding */
}

.outline-module {
    margin-bottom: 1.5rem;
}

.outline-module:last-child {
    margin-bottom: 0;
}

.outline-module-header {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin-bottom: 0.75rem;
    padding-bottom: 0.5rem;
    border-bottom: 1px solid #f1f5f9;
}

.outline-module-number {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 24px;
    height: 24px;
    background: linear-gradient(135deg, #3b82f6, #1d4ed8);
    color: white;
    border-radius: 50%;
    font-size: 0.75rem;
    font-weight: 600;
    flex-shrink: 0;
}

.outline-module-title {
    font-size: 1rem;
    font-weight: 600;
    color: #1f2937;
    margin: 0;
    line-height: 1.4;
}

.outline-lessons {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.outline-lesson-link {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.75rem;
    border-radius: 8px;
    transition: all 0.3s ease;
    border: 1px solid transparent;
    background: #f8fafc;
}

.outline-lesson-link:hover {
    background: #f1f5f9;
    border-color: #e2e8f0;
    transform: translateX(4px);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.outline-lesson-link:hover .outline-lesson-title {
    color: #3b82f6;
}

.outline-lesson-number {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 20px;
    height: 20px;
    background: #e2e8f0;
    color: #64748b;
    border-radius: 4px;
    font-size: 0.75rem;
    font-weight: 500;
    flex-shrink: 0;
}

.outline-lesson-title {
    flex: 1;
    font-size: 0.875rem;
    color: #374151;
    font-weight: 500;
    line-height: 1.4;
    margin: 0;
}

.outline-lesson-duration {
    font-size: 0.75rem;
    color: #9ca3af;
    font-weight: 500;
    flex-shrink: 0;
}

/* Sidebar Card - Isolated styling for better separation */
.content-sidebar .sidebar-card {
    background: white;
    border: 1px solid #e5e7eb;
    border-radius: 12px;
    padding: 0; /* 移除所有padding，让内部元素控制间距 */
    position: relative;
    overflow: hidden;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
    margin-bottom: 0; /* 移除margin，使用flex gap */
    transition: all 0.3s ease;
    /* 为sidebar-card添加独立滚动功能 */
    max-height: calc(100vh - 200px); /* 为每个card设置最大高度 */
    overflow-y: auto;
    /* 自定义滚动条样式 */
    scrollbar-width: thin;
    scrollbar-color: #cbd5e1 #f1f5f9;
    flex-shrink: 0; /* 防止卡片被压缩 */
}

/* Ensure sidebar cards don't inherit main content styles */
.content-sidebar .sidebar-card h1,
.content-sidebar .sidebar-card h2,
.content-sidebar .sidebar-card h3,
.content-sidebar .sidebar-card h4,
.content-sidebar .sidebar-card h5,
.content-sidebar .sidebar-card h6 {
    margin-top: 0 !important; /* 重置顶部margin，避免与main content冲突 */
    margin-bottom: 0.5rem !important;
    font-family: var(--font-primary) !important;
    color: #111827 !important;
    line-height: 1.3 !important;
    letter-spacing: -0.01em !important;
}

/* Enhanced Sidebar Card Visual Hierarchy */
.content-sidebar .sidebar-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px; /* 稍微增加顶部线条高度 */
    background: linear-gradient(90deg, #3b82f6, #8b5cf6); /* 使用渐变色彩 */
    transform: scaleX(0);
    transition: transform 0.3s ease;
    z-index: 1;
}

.content-sidebar .sidebar-card:hover::before {
    transform: scaleX(1);
}

/* Payment Card Specific Enhancements */
.content-sidebar .pricing-card::before {
    content: '' !important;
    position: absolute !important;
    top: 0 !important;
    left: 0 !important;
    right: 0 !important;
    height: 3px !important; /* 稍微增加顶部线条高度 */
    background: linear-gradient(90deg, #10b981, #059669) !important; /* 绿色渐变，表示付费内容 */
    transform: scaleX(0) !important;
    transition: transform 0.3s ease !important;
    z-index: 1 !important;
}

.content-sidebar .pricing-card:hover::before {
    transform: scaleX(1) !important;
}

/* Speaker Card Specific Enhancements */
.content-sidebar .sidebar-card:has(.speaker-info)::before {
    background: linear-gradient(90deg, #f59e0b, #d97706) !important; /* 橙色渐变，表示讲师信息 */
}

/* Content Outline Card Specific Enhancements */
.content-outline-card::before {
    content: '' !important;
    position: absolute !important;
    top: 0 !important;
    left: 0 !important;
    right: 0 !important;
    height: 3px !important; /* 稍微增加顶部线条高度 */
    background: linear-gradient(90deg, #8b5cf6, #7c3aed) !important; /* 紫色渐变，表示内容大纲 */
    transform: scaleX(0) !important;
    transition: transform 0.3s ease !important;
    z-index: 1 !important;
}

.content-outline-card:hover::before {
    transform: scaleX(1) !important;
}

.content-sidebar .sidebar-card:hover {
    border-color: #cbd5e1;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.12);
    transform: translateY(-2px);
}

/* Premium Membership Card - Improved spacing and isolation */
.content-sidebar .pricing-card {
    background: white !important;
    border: 1px solid #e5e7eb !important;
    border-radius: 12px !important;
    padding: 0 !important;
    position: relative !important;
    overflow: hidden !important;
    transition: all 0.3s ease !important;
    display: flex !important;
    flex-direction: column !important;
    height: auto !important;
    min-height: auto !important;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08) !important;
    margin-bottom: 1.5rem !important; /* 卡片间距 */
}

.content-sidebar .pricing-card:hover {
    transform: translateY(-2px) !important;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1) !important;
    border-color: #cbd5e1 !important;
}

/* Premium Membership Header - Improved spacing */
.content-sidebar .pricing-card .course-header {
    padding: 1.5rem 1.5rem 0.75rem 1.5rem !important; /* 统一padding，顶部间距更大 */
    position: relative !important;
    display: flex !important;
    flex-direction: column !important;
    flex: 1 !important;
    background: white !important;
    border-radius: 12px 12px 0 0 !important; /* 顶部圆角 */
}

.content-sidebar .pricing-card .course-title {
    font-family: var(--font-primary) !important;
    font-size: 1.5rem !important;
    font-weight: var(--font-weight-bold) !important;
    color: #111827 !important;
    margin-bottom: 0.75rem !important; /* 减少底部间距，与course-header的padding配合 */
    line-height: 1.3 !important;
    letter-spacing: -0.01em !important;
    height: auto !important;
    overflow: visible !important;
    display: block !important;
    -webkit-line-clamp: unset !important;
    -webkit-box-orient: unset !important;
    text-overflow: unset !important;
}

.content-sidebar .pricing-card .course-description {
    font-family: var(--font-secondary) !important;
    color: #6b7280 !important;
    line-height: 1.5 !important;
    margin-bottom: 0 !important;
    font-size: 0.95rem !important;
    font-weight: var(--font-weight-normal) !important;
    flex: 1 !important;
    overflow: visible !important;
    display: block !important;
    -webkit-line-clamp: unset !important;
    -webkit-box-orient: unset !important;
    text-overflow: unset !important;
}

/* Premium Membership Price Section */
.content-sidebar .pricing-card .course-price-section {
    padding: 1rem 1.5rem !important; /* 统一padding */
    background: linear-gradient(135deg, #f8fafc 0%, #f1f5f9 100%) !important;
    border-top: 1px solid #e5e7eb !important;
    margin-top: 0 !important;
    margin-bottom: 0 !important;
    flex-shrink: 0 !important;
}

.content-sidebar .pricing-card .price {
    font-size: 2rem !important;
    font-weight: 700 !important;
    color: #1a1a1a !important;
    margin-bottom: 0.5rem !important;
    display: flex !important;
    align-items: baseline !important;
    gap: 0.25rem !important;
}

.content-sidebar .pricing-card .price-currency {
    font-size: 1.2rem !important;
    color: #6b7280 !important;
}

.content-sidebar .pricing-card .price-amount {
    font-size: 2.5rem !important;
    color: #3b82f6 !important;
}

.content-sidebar .pricing-card .price-period {
    font-size: 0.9rem !important;
    color: #6b7280 !important;
    font-weight: 500 !important;
}

.content-sidebar .pricing-card .price-note {
    font-size: 0.8rem !important;
    color: #6b7280 !important;
    margin-top: 0.25rem !important;
}

/* Premium Membership CTA */
.content-sidebar .pricing-card .membership-cta {
    padding: 1rem 1.5rem !important; /* 统一padding */
    background: white !important;
    border-top: 1px solid #e5e7eb !important;
    text-align: center !important;
    border-radius: 0 0 12px 12px !important; /* 底部圆角 */
}

.content-sidebar .pricing-card .subscribe-btn {
    background: linear-gradient(135deg, #3b82f6 0%, #1d4ed8 100%) !important;
    color: white !important;
    padding: 0.875rem 1.5rem !important;
    border: none !important;
    border-radius: 12px !important;
    font-weight: 600 !important;
    font-size: 0.95rem !important;
    cursor: pointer !important;
    transition: all 0.3s ease !important;
    box-shadow: 0 4px 15px rgba(59, 130, 246, 0.3) !important;
    width: 100% !important;
    margin-bottom: 0 !important;
}

.content-sidebar .pricing-card .subscribe-btn:hover {
    transform: translateY(-2px) !important;
    box-shadow: 0 8px 25px rgba(59, 130, 246, 0.4) !important;
    background: linear-gradient(135deg, #1d4ed8 0%, #1e40af 100%) !important;
}

/* Legacy Membership Features - Keep for backward compatibility */
.membership-features {
    padding: 1rem 1.25rem;
    background: white;
    border-top: 1px solid #e5e7eb;
}

.membership-features h4 {
    font-size: 1rem;
    font-weight: 600;
    color: #1a1a1a;
    margin-bottom: 1rem;
}

.membership-features ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

.membership-features li {
    padding: 0.5rem 0;
    font-size: 0.9rem;
    color: #64748b;
    border-bottom: 1px solid #f1f5f9;
}

.membership-features li:last-child {
    border-bottom: none;
}

.membership-guarantee {
    font-size: 0.8rem;
    color: #64748b;
    margin: 0;
}


/* Course Information */
.course-info h3 {
    font-size: 1.25rem;
    font-weight: 600;
    color: #1a1a1a;
    margin-bottom: 1.5rem;
}

.info-list {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.info-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.75rem 0;
    border-bottom: 1px solid #f1f5f9;
}

.info-item:last-child {
    border-bottom: none;
}

.info-label {
    font-weight: 500;
    color: #64748b;
}

.info-value {
    font-weight: 600;
    color: #1a1a1a;
}

/* Instructor Info */
.instructor-info h3 {
    font-size: 1.25rem;
    font-weight: 600;
    color: #1a1a1a;
    margin-bottom: 1.5rem;
}

.instructor-profile {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
}

.instructor-avatar {
    width: 80px;
    height: 80px;
    border-radius: 50%;
    object-fit: cover;
    margin-bottom: 1rem;
    border: 4px solid #e5e7eb;
}

.instructor-details h4 {
    font-size: 1.1rem;
    font-weight: 600;
    color: #1a1a1a;
    margin-bottom: 0.25rem;
}

.instructor-title {
    color: #3b82f6;
    font-size: 0.9rem;
    font-weight: 500;
    margin-bottom: 0.75rem;
}

.instructor-bio {
    color: #64748b;
    font-size: 0.9rem;
    line-height: 1.5;
    margin-bottom: 1rem;
}

.instructor-stats {
    display: flex;
    gap: 1rem;
    font-size: 0.85rem;
    color: #64748b;
}

/* Sidebar Information - Improved spacing and isolation */
.content-sidebar .sidebar-card .course-header {
    margin-bottom: 0;
    padding: 1.5rem 1.5rem 0.75rem 1.5rem; /* 统一padding，顶部间距更大 */
    background: white;
    border-radius: 12px 12px 0 0; /* 顶部圆角 */
}

.content-sidebar .sidebar-card .course-header .course-title {
    font-family: var(--font-primary);
    font-weight: var(--font-weight-semibold);
    color: #111827;
    margin-bottom: 0.5rem; /* 添加底部间距 */
    font-size: 1.25rem !important;
    line-height: 1.3;
    letter-spacing: -0.01em;
}

.content-sidebar .sidebar-card .speaker-info {
    margin-bottom: 0;
    padding-bottom: 0;
}

/* Speaker description alignment - ensure left alignment */
.content-sidebar .sidebar-card .speaker-bio {
    text-align: left !important;
}

.content-sidebar .sidebar-card .speaker-title-text {
    text-align: left !important;
}

/* QCon Style Speaker Information */
.qcon-speaker-card {
    background: white !important;
    border: 1px solid #e5e7eb !important;
    border-radius: 8px !important;
    padding: 1.5rem !important;
    margin-bottom: 1.5rem !important;
}

.qcon-speaker-title {
    font-family: var(--font-primary) !important;
    font-size: 1rem !important;
    font-weight: var(--font-weight-semibold) !important;
    color: #374151 !important;
    margin-bottom: 1rem !important;
    text-transform: uppercase !important;
    letter-spacing: 0.05em !important;
}

.qcon-speaker-info {
    display: flex;
    flex-direction: column;
}

.qcon-speaker-name {
    font-family: var(--font-primary) !important;
    font-size: 1.125rem !important;
    font-weight: var(--font-weight-semibold) !important;
    color: #111827 !important;
    margin-bottom: 0.5rem !important;
    line-height: 1.4 !important;
    letter-spacing: -0.005em !important;
}

.qcon-speaker-title-text {
    font-family: var(--font-secondary);
    font-size: 0.875rem;
    font-weight: var(--font-weight-normal);
    color: #6b7280;
    margin-bottom: 0.75rem;
    line-height: 1.4;
}

.qcon-speaker-bio {
    font-family: var(--font-secondary);
    font-size: 0.875rem;
    font-weight: var(--font-weight-normal);
    color: #6b7280;
    line-height: 1.5;
    margin-bottom: 1rem;
}

.qcon-speaker-links {
    display: flex;
    gap: 1rem;
    padding-top: 0.75rem;
    border-top: 1px solid #e5e7eb;
}

.qcon-speaker-link {
    color: #6b7280;
    text-decoration: none;
    font-size: 0.875rem;
    font-weight: 500;
    transition: color 0.2s ease;
}

.qcon-speaker-link:hover {
    color: #3b82f6;
}

/* QCon Style Date Information */
.qcon-date-card {
    background: white !important;
    border: 1px solid #e5e7eb !important;
    border-radius: 8px !important;
    padding: 1.5rem !important;
    margin-bottom: 1.5rem !important;
}

.qcon-date-title {
    font-size: 1rem;
    font-weight: 600;
    color: #374151;
    margin-bottom: 1rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.qcon-date-info {
    display: flex;
    flex-direction: column;
}

.qcon-date-text {
    font-size: 1rem;
    font-weight: 500;
    color: #111827;
    margin-bottom: 0.5rem;
}

.qcon-duration {
    font-size: 0.875rem;
    color: #6b7280;
}

/* QCon Style Share Section */
.qcon-share-card {
    background: white !important;
    border: 1px solid #e5e7eb !important;
    border-radius: 8px !important;
    padding: 1.5rem !important;
    margin-bottom: 1.5rem !important;
}

.qcon-share-title {
    font-size: 1rem;
    font-weight: 600;
    color: #374151;
    margin-bottom: 1rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.qcon-share-buttons {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.qcon-share-btn {
    display: inline-block;
    padding: 0.75rem 1rem;
    background: #f9fafb;
    border: 1px solid #d1d5db;
    border-radius: 6px;
    color: #374151;
    text-decoration: none;
    font-size: 0.875rem;
    font-weight: 500;
    text-align: center;
    transition: all 0.2s ease;
}

.qcon-share-btn:hover {
    background: #f3f4f6;
    border-color: #9ca3af;
    color: #111827;
}

/* Legacy Share Course styles for backward compatibility */
.share-course h3 {
    font-size: 1.25rem;
    font-weight: 600;
    color: #1a1a1a;
    margin-bottom: 1.5rem;
}

/* Related Courses - Using courses page styling */
.related-courses {
    padding: 80px 0;
    background: white;
}

.related-courses .pricing-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 1rem;
}

.related-courses .pricing-card {
    background: white;
    border-radius: 20px;
    padding: 0;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
    border: 1px solid #e5e7eb;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    overflow: hidden;
    display: flex;
    flex-direction: column;
    height: 100%;
    min-height: 300px;
}

.related-courses .pricing-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, #3b82f6, #8b5cf6, #10b981);
    transform: scaleX(0);
    transition: transform 0.4s ease;
}

.related-courses .pricing-card:hover::before {
    transform: scaleX(1);
}

.related-courses .pricing-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.15);
    border-color: #cbd5e1;
}

.related-courses .course-header {
    padding: 1.25rem 1.25rem 0.75rem 1.25rem;
    position: relative;
    display: flex;
    flex-direction: column;
    flex: 1;
}

.related-courses .course-title {
    font-family: var(--font-primary);
    font-size: 1.5rem;
    font-weight: var(--font-weight-bold);
    color: #111827;
    margin-bottom: 1rem;
    line-height: 1.3;
    letter-spacing: -0.01em;
    height: 2.6rem;
    overflow: hidden;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    text-overflow: ellipsis;
}

.related-courses .course-description {
    font-family: var(--font-secondary);
    color: #6b7280;
    line-height: 1.5;
    margin-bottom: 0;
    font-size: 0.95rem;
    font-weight: var(--font-weight-normal);
    flex: 1;
    overflow: hidden;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    text-overflow: ellipsis;
}

.related-courses .course-price-section {
    padding: 1rem 1.25rem;
    background: linear-gradient(135deg, #f8fafc 0%, #f1f5f9 100%);
    border-top: 1px solid #e5e7eb;
    margin-top: 0;
    margin-bottom: 0;
    flex-shrink: 0;
}

.related-courses .price {
    font-size: 2rem;
    font-weight: 700;
    color: #1a1a1a;
    margin-bottom: 0.5rem;
    display: flex;
    align-items: baseline;
    gap: 0.25rem;
}

.related-courses .price-currency {
    font-size: 1.2rem;
    color: #6b7280;
}

.related-courses .price-amount {
    font-size: 2.5rem;
    color: #3b82f6;
}

.related-courses .price-period {
    font-size: 0.9rem;
    color: #6b7280;
    font-weight: 500;
}

.related-courses .price-note {
    font-size: 0.8rem;
    color: #6b7280;
    margin-top: 0.25rem;
}

.related-courses .course-card-link {
    display: flex;
    flex-direction: column;
    text-decoration: none;
    color: inherit;
    height: 100%;
    transition: all 0.3s ease;
}

.related-courses .course-card-link:hover {
    text-decoration: none;
    color: inherit;
}

.related-courses .pricing-card:hover .course-title {
    color: #3b82f6;
}

.related-courses .pricing-card:hover .price-amount {
    color: #1d4ed8;
}

/* Category specific styles for related courses */
.related-courses .pricing-card[data-category="individual"] {
    border-left: 4px solid #10b981;
}

.related-courses .pricing-card[data-category="group"] {
    border-left: 4px solid #f59e0b;
}

.related-courses .pricing-card[data-category="advanced"] {
    border-left: 4px solid #8b5cf6;
}

/* Responsive Design */
@media (max-width: 1200px) {
    .content-layout {
        grid-template-columns: 1fr 360px; /* Main content, Sidebar */
        gap: 2rem;
    }
    
    /* 调整左侧tab的定位 */
    .content-left-tabs {
        left: max(20px, calc((100vw - 1200px) / 2 + 20px)); /* 适配较小屏幕 */
    }
    
    
    /* Premium Membership responsive adjustments */
    .content-sidebar .pricing-card .course-title {
        font-size: 1.4rem !important;
    }
    
    .content-sidebar .pricing-card .price {
        font-size: 1.8rem !important;
    }
    
    .content-sidebar .pricing-card .price-amount {
        font-size: 2.2rem !important;
    }
}

@media (max-width: 968px) {
    .content-layout {
        grid-template-columns: 1fr;
        gap: 2rem;
        padding: 0 1rem;
    }
    
    /* Hide left tabs on mobile */
    .content-left-tabs {
        display: none;
    }
    
    .sidebar-wrapper {
        order: -1;
    }
    
    /* 移动端禁用sticky定位 */
    .sidebar-wrapper {
        position: static !important;
        max-height: none !important;
        overflow-y: visible !important;
    }
    
    .content-sidebar {
        position: static !important;
        max-height: none !important;
        overflow-y: visible !important;
        gap: 1rem; /* 移动端减少间距 */
    }
    
    /* 移动端sidebar-card滚动优化 */
    .content-sidebar .sidebar-card {
        max-height: none !important; /* 移动端移除最大高度限制 */
        overflow-y: visible !important; /* 移动端允许内容自然展开 */
    }
    
    /* 移动端content-main对齐优化 */
    .content-main {
        padding-top: 0; /* 移动端移除顶部padding */
    }
    
    /* Content outline mobile adjustments */
    .content-outline-card .course-header {
        padding: 1.25rem 1.25rem 0.5rem 1.25rem !important; /* 移动端保持顶部间距 */
    }
    
    .content-outline {
        padding: 0 1.25rem 1.25rem 1.25rem !important; /* 移动端padding */
    }
    
    .outline-lesson-link {
        padding: 0.625rem;
    }
    
    .outline-lesson-title {
        font-size: 0.8rem;
    }
    
    /* Premium Membership mobile adjustments */
    .content-sidebar .pricing-card {
        margin-bottom: 2rem !important;
    }
    
    .content-sidebar {
        padding-top: 1.75rem; /* 移动端添加顶部间距，与h1标题对齐 */
    }
    
    .content-sidebar .pricing-card .course-header {
        padding: 1.25rem 1rem 0.5rem 1rem !important; /* 移动端保持顶部间距 */
    }
    
    .content-sidebar .pricing-card .course-title {
        font-size: 1.3rem !important;
        margin-bottom: 0.75rem !important;
    }
    
    .content-sidebar .pricing-card .course-description {
        font-size: 0.9rem !important;
    }
    
    .content-sidebar .pricing-card .course-price-section {
        padding: 0.875rem 1rem !important; /* 移动端保持统一padding */
    }
    
    .content-sidebar .pricing-card .price {
        font-size: 1.75rem !important;
    }
    
    .content-sidebar .pricing-card .price-amount {
        font-size: 2rem !important;
    }
    
    .content-sidebar .pricing-card .membership-cta {
        padding: 0.875rem 1rem !important; /* 移动端保持统一padding */
    }
    
    .content-sidebar .pricing-card .subscribe-btn {
        padding: 1rem 1.5rem !important;
        font-size: 1rem !important;
    }
    
    .course-stats {
        grid-template-columns: repeat(2, 1fr);
        gap: 1rem;
    }
    
    .content-types {
        grid-template-columns: 1fr;
    }
    
    .outcomes-grid {
        grid-template-columns: 1fr;
    }
    
    .reviews-container {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .course-hero {
        padding: 60px 0;
    }
    
    .course-title {
        font-size: 2.5rem;
        line-height: 1.25;
        word-wrap: break-word;
        overflow-wrap: break-word;
        hyphens: auto;
        -webkit-hyphens: auto;
        -ms-hyphens: auto;
    }
    
    .course-subtitle {
        font-size: 1.1rem;
    }
    
    .course-stats {
        grid-template-columns: 1fr;
        gap: 1rem;
    }
    
    .stat-item {
        padding: 0.75rem;
    }
    
    .course-content {
        padding: 30px 0 60px 0;
    }
    
    .content-layout {
        padding: 0;
    }
    
    .content-section h2 {
        font-size: 1.75rem;
    }
    
    /* Course description content mobile adjustments */
    .content-section p {
        margin: 1.25rem 0;
        font-size: 0.95rem;
    }
    
    .content-section h3 {
        margin: 2rem 0 1.25rem 0;
        font-size: 1.3rem;
    }
    
    .content-section ul,
    .content-section ol {
        margin: 1.25rem 0;
        padding-left: 1.25rem;
    }
    
    .content-section li {
        font-size: 0.95rem;
        margin-bottom: 0.4rem;
        margin-top: 0.4rem;
    }
    
    /* Markdown content mobile adjustments */
    .content-section img {
        margin: 1.25rem 0;
        border-radius: 6px;
    }
    
    .content-section table {
        margin: 1.25rem 0;
        font-size: 0.9rem;
    }
    
    .content-section th,
    .content-section td {
        padding: 0.5rem 0.75rem;
    }
    
    .content-section blockquote {
        margin: 1.25rem 0;
        padding: 0.875rem 1.25rem;
    }
    
    .content-section pre,
    .course-content-wrapper pre {
        margin: 1.25rem 0;
        padding: 1.25rem;
        font-size: 0.85rem;
    }
    
    /* Mobile: Ensure course content wrapper handles large content properly */
    .course-content-wrapper {
        overflow-x: auto;
        overflow-y: visible;
        -webkit-overflow-scrolling: touch; /* Smooth scrolling on iOS */
    }
    
    .course-content-wrapper table {
        font-size: 0.85rem; /* Smaller font for tables on mobile */
    }
    
    .content-section h1 {
        font-size: 1.75rem;
        margin: 1.75rem 0 0.875rem 0; /* 恢复原有的上间距 */
        line-height: 1.3;
        word-wrap: break-word;
        overflow-wrap: break-word;
        hyphens: auto;
        -webkit-hyphens: auto;
        -ms-hyphens: auto;
    }
    
    .content-section h2 {
        font-size: 1.5rem;
        margin: 1.75rem 0 0.875rem 0;
        line-height: 1.35;
        word-wrap: break-word;
        overflow-wrap: break-word;
        hyphens: auto;
        -webkit-hyphens: auto;
        -ms-hyphens: auto;
    }
    
    .content-section h4 {
        font-size: 1.1rem;
        margin: 1.5rem 0 0.75rem 0;
        line-height: 1.4;
        word-wrap: break-word;
        overflow-wrap: break-word;
        hyphens: auto;
        -webkit-hyphens: auto;
        -ms-hyphens: auto;
    }
    
    .content-section h5 {
        font-size: 1rem;
        margin: 1.5rem 0 0.75rem 0;
        line-height: 1.45;
        word-wrap: break-word;
        overflow-wrap: break-word;
        hyphens: auto;
        -webkit-hyphens: auto;
        -ms-hyphens: auto;
    }
    
    .content-section h6 {
        font-size: 0.95rem;
        margin: 1.5rem 0 0.75rem 0;
        line-height: 1.45;
        word-wrap: break-word;
        overflow-wrap: break-word;
        hyphens: auto;
        -webkit-hyphens: auto;
        -ms-hyphens: auto;
    }
    
    /* Curriculum responsive styles moved to linkedkeeper-curriculum.css */
    
    .module-content {
        padding: 0 1.5rem 1.5rem 1.5rem;
    }
    
    .related-courses {
        padding: 60px 0;
    }
    
    .related-courses .pricing-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
        padding: 0 0.5rem;
    }
    
    .related-courses .pricing-card {
        border-radius: 16px;
    }
    
    .related-courses .course-header {
        padding: 0.875rem 0.875rem 0.375rem 0.875rem;
    }
    
    .related-courses .course-title {
        font-size: 1.3rem;
        height: 2.34rem;
    }
    
    .related-courses .course-description {
        font-size: 0.9rem;
    }
    
    .related-courses .course-price-section {
        padding: 0.875rem 1rem;
    }
    
    .related-courses .price {
        font-size: 1.75rem;
    }
    
    .related-courses .price-amount {
        font-size: 2rem;
    }
}

@media (max-width: 480px) {
    .course-title {
        font-size: 2rem;
        line-height: 1.3;
        word-wrap: break-word;
        overflow-wrap: break-word;
        hyphens: auto;
        -webkit-hyphens: auto;
        -ms-hyphens: auto;
    }
    
    .course-meta {
        flex-direction: column;
        gap: 0.75rem;
    }
    
    .course-category,
    .course-level,
    .course-duration {
        align-self: flex-start;
    }
    
    /* Premium Membership small screen adjustments */
    .content-sidebar {
        padding-top: 1.5rem; /* 小屏幕添加顶部间距，与h1标题对齐 */
    }
    
    .content-sidebar .pricing-card .course-header {
        padding: 1rem 0.875rem 0.375rem 0.875rem !important; /* 小屏幕保持顶部间距 */
    }
    
    .content-sidebar .pricing-card .course-title {
        font-size: 1.2rem !important;
        margin-bottom: 0.5rem !important;
    }
    
    .content-sidebar .pricing-card .course-description {
        font-size: 0.85rem !important;
    }
    
    .content-sidebar .pricing-card .course-price-section {
        padding: 0.75rem 0.875rem !important; /* 小屏幕保持统一padding */
    }
    
    .content-sidebar .pricing-card .price {
        font-size: 1.5rem !important;
    }
    
    .content-sidebar .pricing-card .price-amount {
        font-size: 1.75rem !important;
    }
    
    .content-sidebar .pricing-card .price-period {
        font-size: 0.8rem !important;
    }
    
    .content-sidebar .pricing-card .price-note {
        font-size: 0.75rem !important;
    }
    
    .content-sidebar .pricing-card .membership-cta {
        padding: 0.75rem 0.875rem !important; /* 小屏幕保持统一padding */
    }
    
    .content-sidebar .pricing-card .subscribe-btn {
        padding: 0.875rem 1.25rem !important;
        font-size: 0.9rem !important;
    }
    
    .membership-header {
        padding: 1.5rem 1rem;
    }
    
    .membership-title {
        font-size: 1.75rem;
    }
    
    .membership-title::after {
        right: -1.5rem;
        font-size: 1.25rem;
    }
    
    .membership-pricing {
        padding: 1.5rem 1rem;
    }
    
    .membership-price {
        flex-direction: column;
        align-items: center;
        gap: 0.25rem;
    }
    
    .membership-amount {
        font-size: 3rem;
    }
    
    .membership-features {
        padding: 1rem;
    }
    
    .membership-features li {
        padding: 0.75rem;
        font-size: 0.9rem;
    }
    
    .subscribe-btn {
        padding: 1rem 1.5rem;
        font-size: 1rem;
    }
    
    .share-buttons {
        grid-template-columns: 1fr;
    }
    
    /* New sections responsive styles */
    .speaker-profile {
        flex-direction: row;
        text-align: left;
        align-items: flex-start;
    }
    
    .speaker-avatar {
        width: 100px !important;
        height: 100px !important;
        margin-right: 1rem;
        margin-bottom: 0;
        flex-shrink: 0;
    }
    
    .speaker-details {
        flex: 1;
    }
    
    .speaker-bio {
        font-size: 0.8rem;
    }
    
    .speaker-links {
        justify-content: flex-start;
        gap: 0.75rem;
    }
    
    .date-time {
        flex-direction: row;
        justify-content: space-between;
        align-items: center;
    }
    
    .date-day {
        font-size: 0.9rem;
    }
    
    .date-date {
        font-size: 1.25rem;
    }
    
    .date-time-text {
        font-size: 0.8rem;
    }
    
    .share-buttons {
        grid-template-columns: 1fr 1fr;
        gap: 0.5rem;
    }
    
    .share-btn {
        padding: 0.5rem 0.75rem;
        font-size: 0.8rem;
    }
    
    .related-courses .pricing-grid {
        padding: 0;
    }
    
    .related-courses .course-header {
        padding: 0.75rem 0.75rem 0.25rem 0.75rem;
    }
    
    .related-courses .course-title {
        height: 2.08rem;
    }
    
    .related-courses .course-price-section {
        padding: 0.75rem 0.875rem;
    }
    
    /* Additional mobile styles for new sections */
    .speaker-profile {
        flex-direction: column;
        text-align: center;
        align-items: center;
    }
    
    .speaker-avatar {
        width: 100px !important;
        height: 100px !important;
        margin-right: 0;
        margin-bottom: 1rem;
    }
    
    .speaker-bio {
        font-size: 0.85rem;
        text-align: center;
    }
    
    .speaker-links {
        justify-content: center;
    }
    
    .date-time {
        flex-direction: column;
        text-align: center;
    }
    
    .share-buttons {
        grid-template-columns: 1fr;
        gap: 0.5rem;
    }
    
    .share-btn {
        padding: 0.75rem 1rem;
        font-size: 0.85rem;
    }
    
    /* Course description content small mobile adjustments */
    .content-section p {
        margin: 1rem 0;
        font-size: 0.9rem;
    }
    
    .content-section h3 {
        margin: 1.75rem 0 1rem 0;
        font-size: 1.2rem;
    }
    
    .content-section ul,
    .content-section ol {
        margin: 1rem 0;
        padding-left: 1rem;
    }
    
    .content-section li {
        font-size: 0.9rem;
        margin-bottom: 0.4rem;
        margin-top: 0.4rem;
    }
    
    .content-section li > p {
        margin-top: 0;
        margin-bottom: 0;
    }
    
    /* Markdown content small mobile adjustments */
    .content-section img {
        margin: 1rem 0;
        border-radius: 4px;
    }
    
    .content-section table {
        margin: 1rem 0;
        font-size: 0.8rem;
    }
    
    .content-section th,
    .content-section td {
        padding: 0.4rem 0.5rem;
    }
    
    .content-section blockquote {
        margin: 1rem 0;
        padding: 0.75rem 1rem;
        font-size: 0.9rem;
    }
    
    .content-section pre,
    .course-content-wrapper pre {
        margin: 1rem 0;
        padding: 1rem;
        font-size: 0.8rem;
    }
    
    /* Small mobile: Ensure course content wrapper handles large content properly */
    .course-content-wrapper {
        overflow-x: auto;
        overflow-y: visible;
        -webkit-overflow-scrolling: touch; /* Smooth scrolling on iOS */
    }
    
    .course-content-wrapper table {
        font-size: 0.75rem; /* Even smaller font for tables on small mobile */
    }
    
    .content-section h1 {
        font-size: 1.5rem;
        margin: 1.5rem 0 0.75rem 0; /* 恢复原有的上间距 */
        line-height: 1.35;
        word-wrap: break-word;
        overflow-wrap: break-word;
        hyphens: auto;
        -webkit-hyphens: auto;
        -ms-hyphens: auto;
    }
    
    .content-section h2 {
        font-size: 1.3rem;
        margin: 1.5rem 0 0.75rem 0;
        line-height: 1.4;
        word-wrap: break-word;
        overflow-wrap: break-word;
        hyphens: auto;
        -webkit-hyphens: auto;
        -ms-hyphens: auto;
    }
    
    .content-section h4 {
        font-size: 1rem;
        margin: 1.25rem 0 0.5rem 0;
        line-height: 1.45;
        word-wrap: break-word;
        overflow-wrap: break-word;
        hyphens: auto;
        -webkit-hyphens: auto;
        -ms-hyphens: auto;
    }
    
    .content-section h5 {
        font-size: 0.95rem;
        margin: 1.25rem 0 0.5rem 0;
        line-height: 1.5;
        word-wrap: break-word;
        overflow-wrap: break-word;
        hyphens: auto;
        -webkit-hyphens: auto;
        -ms-hyphens: auto;
    }
    
    .content-section h6 {
        font-size: 0.9rem;
        margin: 1.25rem 0 0.5rem 0;
        line-height: 1.5;
        word-wrap: break-word;
        overflow-wrap: break-word;
        hyphens: auto;
        -webkit-hyphens: auto;
        -ms-hyphens: auto;
    }
}

/* Animation Keyframes */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

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

/* Apply animations */
.content-section {
    animation: fadeInUp 0.6s ease-out;
}

.sidebar-card {
    animation: slideInRight 0.6s ease-out;
}

.sidebar-card:nth-child(1) { animation-delay: 0.1s; }
.sidebar-card:nth-child(2) { animation-delay: 0.2s; }
.sidebar-card:nth-child(3) { animation-delay: 0.3s; }
.sidebar-card:nth-child(4) { animation-delay: 0.4s; }

/* Related Courses animations */
.related-courses .pricing-card {
    animation: fadeInUp 0.6s ease-out;
}

.related-courses .pricing-card:nth-child(1) { animation-delay: 0.1s; }
.related-courses .pricing-card:nth-child(2) { animation-delay: 0.2s; }
.related-courses .pricing-card:nth-child(3) { animation-delay: 0.3s; }

/* Focus states for accessibility */
.subscribe-btn:focus,
.share-btn:focus,
.module-header:focus {
    outline: 2px solid #3b82f6;
    outline-offset: 2px;
}

/* Print styles */
@media print {
    .course-hero {
        background: white !important;
        color: black !important;
    }
    
    .content-sidebar {
        display: none;
    }
    
    .content-layout {
        grid-template-columns: 1fr;
    }
}