/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f8f9fa;
}

/* Container Layout */
.container {
    display: flex;
    min-height: 100vh;
}

/* Sidebar Navigation */
.sidebar {
    width: 300px;
    background: #2c3e50;
    color: white;
    overflow-y: auto;
    position: fixed;
    height: 100vh;
    left: 0;
    top: 0;
    z-index: 1000;
}

.sidebar-header {
    padding: 20px;
    background: #34495e;
    border-bottom: 1px solid #4a5f7a;
}

/* Sidebar width toggle button */
.sidebar-toggle {
    position: absolute;
    top: 10px;
    right: 10px;
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    color: white;
    padding: 5px 8px;
    border-radius: 4px;
    cursor: pointer;
    font-size: 12px;
    transition: all 0.2s ease;
    z-index: 1001;
}

.sidebar-toggle:hover {
    background: rgba(255, 255, 255, 0.2);
    border-color: rgba(255, 255, 255, 0.3);
}

/* Expanded/collapsed width states */
.sidebar.expanded { width: 500px; max-width: 60vw; }
.sidebar.collapsed { width: 60px; min-width: 60px; }
.sidebar.collapsed .sidebar-header h2,
.sidebar.collapsed .search-container,
.sidebar.collapsed .nav-folder-header span,
.sidebar.collapsed .nav-item span { display: none; }
.sidebar.collapsed .nav-folder-header,
.sidebar.collapsed .nav-item { justify-content: center; }

.sidebar-header h2 {
    font-size: 1.3rem;
    font-weight: 600;
}

.sidebar-header i {
    margin-right: 10px;
    color: #3498db;
}

.sidebar-content {
    padding: 20px 0;
}

/* Sidebar search */
.search-container { padding: 0 16px 12px 16px; }
.search-box { position: relative; display: flex; align-items: center; }
.search-box input {
    width: 100%;
    padding: 8px 12px 8px 32px;
    background: rgba(255,255,255,0.1);
    border: 1px solid rgba(255,255,255,0.2);
    border-radius: 20px;
    color: #fff;
    font-size: 0.9rem;
}
.search-box input::placeholder { color: rgba(255,255,255,0.7); }
.search-icon { position: absolute; left: 10px; color: rgba(255,255,255,0.7); font-size: 0.8rem; }
.clear-search {
    position: absolute;
    right: 6px;
    background: none; border: none; color: rgba(255,255,255,0.7);
    cursor: pointer; padding: 4px; border-radius: 50%; font-size: 0.8rem;
}

/* Navigation Items */
.nav-folder {
    margin-bottom: 2px;
}

.nav-folder-header {
    padding: 10px 20px;
    cursor: pointer;
    display: flex;
    align-items: center;
    transition: background-color 0.2s;
    user-select: none;
}

.nav-folder-header:hover {
    background: #34495e;
}

.nav-folder-header .folder-icon {
    margin-right: 10px;
    color: #f39c12;
    width: 16px;
}

.nav-folder-header .folder-arrow {
    margin-left: auto;
    transition: transform 0.2s;
    font-size: 0.8rem;
}

.nav-folder-header.active .folder-arrow {
    transform: rotate(90deg);
}

.nav-folder-content {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease-out;
    background: rgba(52, 73, 94, 0.3);
}

.nav-folder-content.open {
    max-height: none;
}

.nav-item {
    padding: 8px 20px 8px 45px;
}

/* Multi-level navigation indentation */
.nav-folder-content .nav-folder-header {
    padding-left: 40px;
}

.nav-folder-content .nav-item {
    padding-left: 65px;
}

.nav-folder-content .nav-folder-content .nav-folder-header {
    padding-left: 60px;
}

.nav-folder-content .nav-folder-content .nav-item {
    padding-left: 85px;
}

.nav-folder-content .nav-folder-content .nav-folder-content .nav-folder-header {
    padding-left: 80px;
}

.nav-folder-content .nav-folder-content {
    background: rgba(52, 73, 94, 0.5);
}

.nav-folder-content .nav-folder-content .nav-folder-content {
    background: rgba(52, 73, 94, 0.7);
}

/* Improved folder arrow states */
.nav-folder-header .folder-arrow.open {
    transform: rotate(90deg);
    color: #3498db;
}

/* Better visual separation for nested levels */
.nav-folder-content .nav-folder {
    border-left: 2px solid rgba(52, 152, 219, 0.2);
    margin-left: 10px;
}

.nav-folder-content .nav-folder-content .nav-folder {
    border-left-color: rgba(52, 152, 219, 0.4);
}

/* Improve active state visibility */
.nav-item a.active {
    color: #3498db;
    background: rgba(52, 152, 219, 0.15);
    border-radius: 4px;
    margin: -4px;
    padding: 4px 8px;
    font-weight: 600;
}

.nav-item a {
    color: #bdc3c7;
    text-decoration: none;
    display: flex;
    align-items: center;
    transition: color 0.2s;
}

.nav-item a:hover {
    color: #3498db;
}

.nav-item a.active {
    color: #3498db;
    background: rgba(52, 152, 219, 0.1);
    border-radius: 4px;
    margin: -4px;
    padding: 4px;
}

.nav-item a i {
    margin-right: 8px;
    width: 16px;
    color: #95a5a6;
}

.nav-item a.active i {
    color: #3498db;
}

/* Main Content */
.main-content {
    flex: 1;
    margin-left: 300px;
    padding: 0;
}

.content-wrapper {
    max-width: 1320px;
    margin: 0 auto;
    padding: 30px;
}

/* Breadcrumb */
.breadcrumb {
    margin-bottom: 20px;
    padding: 15px 20px;
    background: white;
    border-radius: 8px;
    border-left: 4px solid #3498db;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 15px;
}

.breadcrumb-nav {
    display: flex;
    gap: 8px;
}

.nav-btn {
    background: #f8f9fa;
    border: 1px solid #dee2e6;
    border-radius: 4px;
    padding: 8px 10px;
    cursor: pointer;
    transition: all 0.2s;
    display: flex;
    align-items: center;
    justify-content: center;
    min-width: 36px;
    height: 36px;
}

.nav-btn:hover:not(:disabled) {
    background: #3498db;
    color: white;
    border-color: #3498db;
}

.nav-btn:disabled {
    cursor: not-allowed;
    opacity: 0.5;
}

.breadcrumb-path {
    flex: 1;
    display: flex;
    align-items: center;
}

.breadcrumb-path a {
    color: #3498db;
    text-decoration: none;
}

.breadcrumb-path a:hover {
    text-decoration: underline;
}

/* Breadcrumb navigation links and current page styling */
.breadcrumb-link {
    color: #3498db;
    text-decoration: none;
    padding: 2px 4px;
    border-radius: 3px;
    transition: all 0.2s ease;
}

.breadcrumb-link:hover {
    color: #2980b9;
    background: rgba(52, 152, 219, 0.1);
    text-decoration: none;
}

.breadcrumb-link:active {
    background: rgba(52, 152, 219, 0.2);
}

.breadcrumb-current {
    color: #2c3e50;
    font-weight: 600;
    padding: 2px 4px;
}

/* Mobile and tablet responsive breadcrumb */
@media (max-width: 768px) {
    .breadcrumb {
        flex-direction: column;
        gap: 10px;
        padding: 12px 15px;
    }
    
    .breadcrumb-nav {
        order: 2;
        justify-content: center;
        width: 100%;
    }
    
    .breadcrumb-path {
        order: 1;
        font-size: 0.9rem;
        flex-wrap: wrap;
        justify-content: center;
        text-align: center;
    }
    
    .breadcrumb-path i.fa-chevron-right {
        margin: 0 4px;
    }
}

@media (max-width: 480px) {
    .breadcrumb-path {
        font-size: 0.8rem;
    }
    
    /* Stack breadcrumb items vertically on very small screens if needed */
    .breadcrumb-path.long-path {
        flex-direction: column;
        align-items: center;
        gap: 5px;
    }
    
    .breadcrumb-path.long-path i.fa-chevron-right {
        transform: rotate(90deg);
        margin: 2px 0;
    }
}

/* Tutorial Navigation */
.tutorial-navigation {
    display: flex;
    justify-content: space-between;
    margin: 20px 0;
    gap: 20px;
}

/* Tutorial actions (buttons row) */
.tutorial-actions { display: flex; gap: 10px; align-items: center; }
.btn-secondary {
    background: #f8f9fa;
    border: 1px solid #dee2e6;
    color: #495057;
    padding: 8px 16px;
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.2s ease;
    font-size: 0.85rem; font-weight: 500; display: inline-flex; align-items: center; gap: 6px;
}
.btn-secondary:hover { background: #e9ecef; border-color: #adb5bd; }

.nav-tutorial {
    flex: 1;
    max-width: 300px;
    padding: 15px 20px;
    background: white;
    border: 1px solid #e1e8ed;
    border-radius: 8px;
    text-decoration: none;
    color: #333;
    transition: all 0.2s;
    display: flex;
    align-items: center;
    gap: 10px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.nav-tutorial:hover:not(.nav-tutorial-disabled) {
    border-color: #3498db;
    box-shadow: 0 4px 12px rgba(52, 152, 219, 0.15);
    transform: translateY(-2px);
}

.nav-tutorial-disabled {
    opacity: 0;
    pointer-events: none;
}

.nav-tutorial-prev {
    text-align: left;
}

.nav-tutorial-next {
    text-align: right;
    justify-content: flex-end;
}

.nav-tutorial-content {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.nav-tutorial-label {
    font-size: 0.85rem;
    color: #666;
    font-weight: 500;
}

.nav-tutorial-title {
    font-weight: 600;
    color: #333;
}

.nav-tutorial i {
    color: #3498db;
    font-size: 1.2rem;
}

/* Responsive Design */
@media (max-width: 768px) {
    .sidebar {
        transform: translateX(-100%);
        transition: transform 0.3s ease;
    }
    
    .sidebar.open {
        transform: translateX(0);
    }
    
    .main-content {
        margin-left: 0;
    }
    
    .container {
        position: relative;
    }
    
    .breadcrumb {
        flex-direction: column;
        align-items: flex-start;
        gap: 10px;
    }
    
    .breadcrumb-nav {
        order: 2;
        align-self: stretch;
        justify-content: center;
    }
    
    .tutorial-navigation {
        flex-direction: column;
        gap: 10px;
    }
    
    .nav-tutorial {
        max-width: none;
    }
    
    .content-wrapper {
        padding: 15px;
    }
}

/* Adjust main content based on sidebar width state (desktop) */
.sidebar.expanded ~ .main-content { margin-left: 500px; }
.sidebar.collapsed ~ .main-content { margin-left: 60px; }

/* Mobile menu toggle */
.mobile-menu-toggle {
    display: none;
    position: fixed;
    top: 20px;
    left: 20px;
    z-index: 1001;
    background: #3498db;
    color: white;
    border: none;
    border-radius: 4px;
    padding: 10px;
    cursor: pointer;
}

@media (max-width: 768px) {
    .mobile-menu-toggle {
        display: block;
    }
}

.breadcrumb i {
    font-size: 0.9rem;
    margin: 0 8px;
    color: #95a5a6;
}

/* ===== Toolbar & Zoom (added) ===== */
.toolbar {
    position: sticky;
    top: 0;
    z-index: 50;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 10px;
    padding: 10px 16px;
    background: #ffffff;
    border-bottom: 1px solid #e1e8ed;
    box-shadow: 0 2px 8px rgba(0,0,0,0.06);
}
.toolbar-left, .toolbar-right { display: flex; align-items: center; gap: 8px; }
.tb-btn {
    display: inline-flex; align-items: center; gap: 6px;
    background: #f8f9fa; color: #333;
    border: 1px solid #e1e8ed;
    padding: 6px 10px; border-radius: 6px; cursor: pointer; font-size: 0.9rem;
    transition: background 0.2s, color 0.2s, border-color 0.2s, transform 0.05s;
}
.tb-btn:hover { background: #e9ecef; border-color: #3498db; color: #3498db; }
.tb-btn:active { transform: translateY(1px); }
.tb-btn i { color: inherit; }
.tb-sep { width: 1px; height: 22px; background: #e1e8ed; margin: 0 4px; }
.tb-indicator { min-width: 44px; text-align: center; color: #7f8c8d; font-variant-numeric: tabular-nums; }
.zoom-container { transform-origin: top left; }

/* Busy overlay */
.busy-overlay { position: fixed; inset: 0; background: rgba(0,0,0,0.15); display: none; align-items: center; justify-content: center; z-index: 9999; }
.busy-overlay.show { display: flex; }
.busy-overlay .spinner { background: #ffffff; border: 1px solid #e1e8ed; padding: 10px 14px; border-radius: 8px; box-shadow: 0 2px 8px rgba(0,0,0,0.1); color: #3498db; }

/* ===== Dark theme overrides (added) ===== */
.theme-dark, .theme-dark body { background: #0f172a; color: #e2e8f0; }
.theme-dark .toolbar { background: #0b1220; border-color: #1f2937; box-shadow: 0 2px 8px rgba(0,0,0,0.5); }
.theme-dark .tb-btn { background: #0f172a; color: #e2e8f0; border-color: #1f2937; }
.theme-dark .tb-btn:hover { background: #111827; color: #60a5fa; border-color: #374151; }
.theme-dark .tb-indicator { color: #94a3b8; }
.theme-dark .markdown-content, .theme-dark .breadcrumb, .theme-dark .feature, .theme-dark .folder-listing { background: #0b1220; box-shadow: 0 2px 8px rgba(0,0,0,0.5); }
.theme-dark .breadcrumb { border-left-color: #60a5fa; }
.theme-dark .breadcrumb-path a, .theme-dark .breadcrumb-link { color: #60a5fa; }
.theme-dark .toc-link { color: #cbd5e1; }
.theme-dark .toc-link:hover { background: #111827; color: #e2e8f0; }
.theme-dark .folder-card, .theme-dark .file-card { background: #0f172a; border-color: #1f2937; }
.theme-dark .folder-card:hover, .theme-dark .file-card:hover { box-shadow: 0 4px 15px rgba(0,0,0,0.5); }
.theme-dark .folder-header { background: linear-gradient(135deg, #1e293b, #0b1220); }
.theme-dark .table-of-contents { background: #0f172a; border-color: #1f2937; }
.theme-dark .busy-overlay .spinner { background: #0b1220; border-color: #1f2937; color: #60a5fa; }

/* Frontmatter */
.frontmatter {
    margin-bottom: 30px;
    padding: 20px;
    background: white;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    border-left: 4px solid #27ae60;
}

.page-title {
    color: #2c3e50;
    margin-bottom: 10px;
    font-size: 2rem;
    font-weight: 600;
}

.page-meta {
    color: #7f8c8d;
    font-size: 0.9rem;
}

.page-meta i {
    margin-right: 5px;
}

/* Markdown Content */
.markdown-content {
    background: white;
    padding: 30px;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    line-height: 1.7;
    transform-origin: top left;
    transform: scale(var(--md-scale, 1));
    width: calc(100% / var(--md-scale, 1));
}

/* Ensure sticky children within content area are not clipped */
.main-content, .content-wrapper, .article-layout {
    overflow: visible;
}

.markdown-content h1,
.markdown-content h2,
.markdown-content h3,
.markdown-content h4,
.markdown-content h5,
.markdown-content h6 {
    color: #2c3e50;
    margin-top: 30px;
    margin-bottom: 15px;
    font-weight: 600;
    line-height: 1.3;
}

.markdown-content h1 {
    font-size: 2rem;
    border-bottom: 2px solid #ecf0f1;
    padding-bottom: 10px;
}

.markdown-content h2 {
    font-size: 1.6rem;
    border-bottom: 1px solid #ecf0f1;
    padding-bottom: 8px;
}

.markdown-content h3 {
    font-size: 1.3rem;
}

.markdown-content p {
    margin-bottom: 16px;
    text-align: justify;
}

.markdown-content ul,
.markdown-content ol {
    margin-bottom: 16px;
    margin-left: 30px;
}

.markdown-content li {
    margin-bottom: 5px;
}

.markdown-content blockquote {
    margin: 16px 0;
    padding: 15px 20px;
    background: #f8f9fa;
    border-left: 4px solid #3498db;
    color: #555;
    font-style: italic;
}

/* Code Block Styling */
.code-block-wrapper {
    margin: 20px 0;
    background: #2d3748;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
}
    pre code {
        white-space: pre;
    }
    pre {
        overflow: auto;
        max-width: 100%;
    }

.code-header {
    background: #1a202c;
    padding: 10px 15px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid #4a5568;
}

.code-language {
    color: #a0aec0;
    font-size: 0.85rem;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.copy-button {
    background: #3182ce;
    color: white;
    border: none;
    padding: 5px 10px;
    border-radius: 4px;
    cursor: pointer;
    font-size: 0.85rem;
    transition: background-color 0.2s;
    display: flex;
    align-items: center;
    gap: 5px;
}

.copy-button:hover {
    background: #2b77cb;
}

.copy-button.copied {
    background: #38a169;
}

.code-block-wrapper pre {
    margin: 0 !important;
    padding: 20px !important;
    background: #2d3748 !important;
    overflow-x: auto;
    font-size: 0.9rem;
    line-height: 1.5;
}

.code-block-wrapper code {
    background: transparent !important;
    padding: 0 !important;
    border: none !important;
    color: #e2e8f0 !important;
}

/* Highlight.js specific overrides */
.code-block-wrapper code.hljs {
    background: transparent !important;
    padding: 0 !important;
}

.code-block-wrapper pre .hljs {
    background: transparent !important;
}

/* Ensure hljs colors work properly */
.hljs {
    color: #e2e8f0 !important;
}

/* Inline Code */
.markdown-content code:not(.code-block-wrapper code) {
    background: #f1f5f9;
    color: #e91e63;
    padding: 2px 6px;
    border-radius: 3px;
    font-size: 0.9em;
    font-family: 'Monaco', 'Menlo', 'Ubuntu Mono', monospace;
}

/* Tables */
.markdown-content table {
    width: 100%;
    border-collapse: collapse;
    margin: 20px 0;
    background: white;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
    border-radius: 8px;
    overflow: hidden;
}

.markdown-content th,
.markdown-content td {
    padding: 12px 15px;
    text-align: left;
    border-bottom: 1px solid #ecf0f1;
}

.markdown-content th {
    background: #f8f9fa;
    font-weight: 600;
    color: #2c3e50;
}

.markdown-content tr:hover {
    background: #f8f9fa;
}

/* Home Page Styling */
.home-page {
    text-align: center;
    padding: 40px 20px;
}

.home-page h1 {
    color: #2c3e50;
    margin-bottom: 20px;
    font-size: 2.5rem;
}

.home-page h1 i {
    color: #3498db;
    margin-right: 15px;
}

.home-page p {
    color: #7f8c8d;
    font-size: 1.1rem;
    margin-bottom: 30px;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
    margin-top: 40px;
}

.feature {
    background: white;
    padding: 30px 20px;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
    transition: transform 0.3s, box-shadow 0.3s;
}

.feature:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(0,0,0,0.15);
}

.feature i {
    font-size: 2.5rem;
    color: #3498db;
    margin-bottom: 15px;
}

.feature h3 {
    color: #2c3e50;
    margin-bottom: 10px;
    font-size: 1.2rem;
}

.feature p {
    color: #7f8c8d;
    font-size: 0.9rem;
    margin: 0;
}

/* Error Page */
.error-page {
    text-align: center;
    padding: 60px 20px;
}

.error-page h1 {
    color: #e74c3c;
    margin-bottom: 20px;
    font-size: 2rem;
}

.error-page h1 i {
    margin-right: 10px;
}

.error-page p {
    color: #7f8c8d;
    margin-bottom: 30px;
    font-size: 1.1rem;
}

.btn {
    display: inline-block;
    background: #3498db;
    color: white;
    padding: 12px 25px;
    text-decoration: none;
    border-radius: 5px;
    transition: background-color 0.2s;
}

.btn:hover {
    background: #2980b9;
}

.btn i {
    margin-right: 8px;
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        flex-direction: column;
    }
    
    .sidebar {
        position: relative;
        width: 100%;
        height: auto;
    }
    
    .main-content {
        margin-left: 0;
    }
    
    .content-wrapper {
        padding: 20px 15px;
    }
    
    .features {
        grid-template-columns: 1fr;
    }
    
    .page-title {
        font-size: 1.5rem;
    }
}

/* Scrollbar Styling */
.sidebar::-webkit-scrollbar {
    width: 6px;
}

.sidebar::-webkit-scrollbar-track {
    background: #34495e;
}

.sidebar::-webkit-scrollbar-thumb {
    background: #4a5f7a;
    border-radius: 3px;
}

.sidebar::-webkit-scrollbar-thumb:hover {
    background: #5a6f8a;
}

/* Selection Styling */
::selection {
    background: #3498db;
    color: white;
}

::-moz-selection {
    background: #3498db;
    color: white;
}

/* Table of Contents Styles */
.table-of-contents {
    background: #f8f9fa;
    border: 1px solid #e9ecef;
    border-radius: 8px;
    padding: 20px;
    margin: 0 0 30px 0;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.toc-title {
    color: #2c3e50;
    font-size: 1.2rem;
    font-weight: 600;
    margin: 0 0 15px 0;
    padding-bottom: 10px;
    border-bottom: 2px solid #3498db;
    display: flex;
    align-items: center;
    gap: 8px;
}

.toc-title i {
    color: #3498db;
}

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

.toc-nested {
    margin-left: 20px;
    margin-top: 5px;
}

.toc-item {
    margin: 5px 0;
}

.toc-link {
    display: block;
    padding: 6px 12px;
    color: #495057;
    text-decoration: none;
    border-radius: 4px;
    transition: all 0.2s ease;
    font-size: 0.95rem;
    line-height: 1.4;
}

.toc-link:hover {
    background: #e9ecef;
    color: #2c3e50;
    text-decoration: none;
    transform: translateX(2px);
}

/* Active section highlighting */
.toc-link.active {
    background: rgba(52, 152, 219, 0.15);
    color: #2c3e50;
    border-left: 3px solid #3498db;
}

.toc-level-1 .toc-link {
    font-weight: 600;
    color: #2c3e50;
    font-size: 1rem;
}

.toc-level-2 .toc-link {
    font-weight: 500;
    padding-left: 20px;
}

.toc-level-3 .toc-link {
    padding-left: 28px;
    font-size: 0.9rem;
}

.toc-level-4 .toc-link {
    padding-left: 36px;
    font-size: 0.85rem;
    color: #6c757d;
}

.toc-level-5 .toc-link,
.toc-level-6 .toc-link {
    padding-left: 44px;
    font-size: 0.8rem;
    color: #6c757d;
}

/* Responsive ToC */
@media (max-width: 768px) {
    .table-of-contents {
        margin: 0 0 20px 0;
        padding: 15px;
    }
    
    .toc-title {
        font-size: 1.1rem;
    }
    
    .toc-nested {
        margin-left: 15px;
    }
    
    .toc-level-2 .toc-link {
        padding-left: 15px;
    }
    
    .toc-level-3 .toc-link {
        padding-left: 22px;
    }
    
    .toc-level-4 .toc-link {
        padding-left: 29px;
    }
    
    .toc-level-5 .toc-link,
    .toc-level-6 .toc-link {
        padding-left: 36px;
    }
}

/* Scroll margin for anchor links */
h1, h2, h3, h4, h5, h6 {
    scroll-margin-top: 20px;
}

/* Ensure anchored headings aren't hidden under the top UI */
.markdown-content h1[id],
.markdown-content h2[id],
.markdown-content h3[id],
.markdown-content h4[id],
.markdown-content h5[id],
.markdown-content h6[id] {
    scroll-margin-top: 80px; /* Adjust if breadcrumb height changes */
}

/* Enhanced Code Block Styling for Highlight.js */
pre {
    background: #2d3748 !important;
    border-radius: 8px;
    margin: 1rem 0;
    overflow: auto;
    max-height: 500px;
    font-size: 0.9rem;
    line-height: 1.5;
    padding: 0;
    max-width: 100%;
}

code {
    font-family: 'Fira Code', 'Monaco', 'Cascadia Code', 'Roboto Mono', 'Courier New', monospace;
    font-size: inherit;
    line-height: inherit;
}

/* Inline code styling */
:not(pre) > code {
    background: #f1f5f9 !important;
    color: #1e293b !important;
    padding: 0.2em 0.4em;
    border-radius: 3px;
    font-size: 0.85em;
    white-space: nowrap;
}

.inline-code {
    background: #f1f5f9 !important;
    color: #1e293b !important;
    padding: 0.2em 0.4em;
    border-radius: 3px;
    font-size: 0.85em;
    white-space: nowrap;
}

/* Code block wrapper improvements */
.code-block-wrapper {
    position: relative;
    margin: 1.5rem 0;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}

.code-block-wrapper pre {
    margin: 0;
    padding: 1rem;
}

.code-header {
    background: #1a202c;
    color: #cbd5e0;
    padding: 0.75rem 1rem;
    font-size: 0.8rem;
    font-weight: 600;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid #4a5568;
}

.code-language {
    text-transform: uppercase;
    letter-spacing: 0.05em;
    font-family: inherit;
}

.copy-button {
    background: #4299e1;
    color: white;
    border: none;
    padding: 0.25rem 0.5rem;
    border-radius: 4px;
    cursor: pointer;
    font-size: 0.75rem;
    transition: all 0.2s ease;
}

.copy-button:hover {
    background: #3182ce;
    transform: translateY(-1px);
}

.copy-button.copied {
    background: #48bb78;
    transform: scale(0.95);
}

/* Copy button for code blocks - iPad friendly */
.copy-btn {
    position: absolute;
    top: 8px;
    right: 8px;
    background: rgba(66, 153, 225, 0.9);
    color: white;
    border: none;
    border-radius: 6px;
    padding: 8px 12px;
    cursor: pointer;
    font-size: 0.75rem;
    font-weight: 500;
    line-height: 1;
    transition: all 0.2s ease;
    z-index: 10;
    display: flex;
    align-items: center;
    gap: 4px;
    opacity: 1; /* Always visible for touch devices */
    backdrop-filter: blur(4px);
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    /* Subtle pulse animation to draw attention */
    animation: copyButtonPulse 3s ease-in-out infinite;
}

@keyframes copyButtonPulse {
    0%, 70%, 100% {
        opacity: 1;
        transform: scale(1);
    }
    35% {
        opacity: 0.8;
        transform: scale(0.98);
    }
}

.copy-btn:hover {
    background: rgba(49, 130, 206, 0.95);
    transform: translateY(-1px);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.15);
    animation: none; /* Stop pulse on hover */
}

.copy-btn:active {
    transform: translateY(0);
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.copy-btn.copied {
    background: rgba(72, 187, 120, 0.9);
    animation: none; /* Stop pulse when copied */
}

.copy-btn.error {
    background: rgba(245, 101, 101, 0.9);
    animation: none; /* Stop pulse on error */
}

/* Stop animation after user interacts */
.copy-btn:focus,
.copy-btn:active {
    animation: none;
}

.copy-btn i {
    font-size: 0.7rem;
}

/* Ensure parent pre has proper positioning */
pre {
    position: relative;
}

/* Make sure code blocks have enough space for the copy button */
pre:has(.copy-btn) {
    padding-top: 3rem !important;
}

/* Add some top padding to code blocks to make room for the copy button */
pre code {
    display: block;
    padding-top: 2.5rem;
}

/* Ensure copy button appears above syntax highlighting */
.copy-btn {
    z-index: 5; /* keep above code but below ToC */
}

/* Mobile and tablet specific styles for copy button */
@media (max-width: 1024px) {
    .copy-btn {
        padding: 10px 14px;
        font-size: 0.8rem;
        min-height: 44px; /* Apple's recommended minimum touch target */
        min-width: 44px;
        top: 6px;
        right: 6px;
    }
    
    .copy-btn i {
        font-size: 0.75rem;
    }
    
    pre code {
        padding-top: 3rem;
    }
}

@media (max-width: 768px) {
    .copy-btn {
        padding: 12px 16px;
        font-size: 0.85rem;
        border-radius: 8px;
    }
}

/* Scrollbar styling for code blocks */
pre::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

pre::-webkit-scrollbar-track {
    background: #1a202c;
}

pre::-webkit-scrollbar-thumb {
    background: #4a5568;
    border-radius: 4px;
}

pre::-webkit-scrollbar-thumb:hover {
    background: #718096;
}

/* Override highlight.js theme for better appearance */
.hljs {
    background: #2d3748 !important;
    color: #e2e8f0 !important;
    padding: 1rem !important;
}

/* Better token colors */
.hljs-comment,
.hljs-quote {
    color: #718096 !important;
    font-style: italic;
}

.hljs-keyword,
.hljs-selector-tag,
.hljs-literal,
.hljs-type,
.hljs-addition {
    color: #9f7aea !important;
}

.hljs-number,
.hljs-selector-attr,
.hljs-selector-pseudo {
    color: #f56565 !important;
}

.hljs-string,
.hljs-doctag {
    color: #68d391 !important;
}

.hljs-title,
.hljs-section,
.hljs-selector-id {
    color: #fbb6ce !important;
    font-weight: bold;
}

.hljs-subst,
.hljs-symbol,
.hljs-bullet,
.hljs-link {
    color: #4fd1c7 !important;
}

.hljs-built_in,
.hljs-builtin-name {
    color: #63b3ed !important;
}

.hljs-meta,
.hljs-meta-keyword {
    color: #a0aec0 !important;
}

.hljs-attr {
    color: #fbb6ce !important;
}

.hljs-variable,
.hljs-template-variable {
    color: #feb2b2 !important;
}

.hljs-class .hljs-title {
    color: #fbb6ce !important;
}

.hljs-tag {
    color: #9f7aea !important;
}

.hljs-name {
    color: #4fd1c7 !important;
}

.hljs-attribute {
    color: #68d391 !important;
}

/* Anchor target highlight and inline Previous button */
.anchor-highlight {
    animation: anchorFlash 1.2s ease-out;
}

@keyframes anchorFlash {
    0% { background-color: rgba(255, 235, 59, 0.6); }
    100% { background-color: transparent; }
}

.anchor-prev-btn {
    margin-left: 12px;
    font-size: 0.85rem;
    padding: 4px 8px;
    border: 1px solid #ced4da;
    background: #f8f9fa;
    color: #333;
    border-radius: 4px;
    cursor: pointer;
    transition: all 0.2s ease;
}

.anchor-prev-btn:hover {
    background: #e9ecef;
    transform: translateY(-1px);
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

/* Folder listing styles */
.folder-listing {
    background: white;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
    overflow: hidden;
}

.folder-header {
    background: linear-gradient(135deg, #3498db, #2980b9);
    color: white;
    padding: 30px;
    text-align: center;
}

.folder-header h1 {
    margin: 0 0 10px 0;
    font-size: 2rem;
    font-weight: 300;
}

.folder-header h1 i {
    margin-right: 10px;
    color: #ecf0f1;
}

.folder-description {
    margin: 0;
    opacity: 0.9;
    font-size: 1.1rem;
}

.folder-contents {
    padding: 30px;
}

.content-section {
    margin-bottom: 40px;
}

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

.content-section h2 {
    color: #2c3e50;
    margin-bottom: 20px;
    padding-bottom: 10px;
    border-bottom: 2px solid #ecf0f1;
    font-size: 1.3rem;
}

.content-section h2 i {
    margin-right: 8px;
    color: #3498db;
}

.folder-grid,
.file-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 15px;
    margin-top: 20px;
}

.folder-card,
.file-card {
    background: #f8f9fa;
    border: 1px solid #e9ecef;
    border-radius: 8px;
    transition: all 0.2s ease;
    overflow: hidden;
}

.folder-card:hover,
.file-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
    border-color: #3498db;
}

.folder-card a,
.file-card a {
    display: flex;
    align-items: center;
    padding: 20px;
    text-decoration: none;
    color: #2c3e50;
    transition: all 0.2s ease;
}

.folder-card a:hover,
.file-card a:hover {
    color: #3498db;
    background: rgba(52, 152, 219, 0.05);
}

.folder-card a i:first-child,
.file-card a i:first-child {
    font-size: 1.5rem;
    margin-right: 15px;
    color: #3498db;
    min-width: 24px;
}

.folder-card a i:first-child {
    color: #f39c12;
}

.folder-card a span,
.file-card a span {
    flex: 1;
    font-weight: 500;
    font-size: 1rem;
}

.folder-card a i:last-child,
.file-card a i:last-child {
    color: #bdc3c7;
    transition: transform 0.2s ease;
}

.folder-card:hover a i:last-child,
.file-card:hover a i:last-child {
    transform: translateX(5px);
    color: #3498db;
}

.empty-folder {
    text-align: center;
    padding: 60px 30px;
    color: #7f8c8d;
}

.empty-folder i {
    font-size: 4rem;
    margin-bottom: 20px;
    display: block;
}

.empty-folder p {
    font-size: 1.1rem;
    margin: 0;
}

/* Responsive folder listing */
@media (max-width: 768px) {
    .folder-grid,
    .file-grid {
        grid-template-columns: 1fr;
        gap: 10px;
    }
    
    .folder-header {
        padding: 20px;
    }
    
    .folder-header h1 {
        font-size: 1.5rem;
    }
    
    .folder-contents {
        padding: 20px;
    }
    
    .content-section {
        margin-bottom: 30px;
    }
}

/* ===== ENHANCED UI FEATURES ===== */

/* Enhanced Search Results */
.search-results-header {
    padding: 10px 20px;
    background: rgba(52, 152, 219, 0.1);
    border-bottom: 1px solid rgba(52, 152, 219, 0.2);
    font-size: 0.9rem;
    color: #3498db;
    display: flex;
    align-items: center;
    gap: 8px;
}

.search-result-item {
    margin: 0;
}

.search-result-item a {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 20px;
    color: #bdc3c7;
    text-decoration: none;
    transition: background-color 0.2s;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.search-result-item a:hover {
    background: #34495e;
    color: #3498db;
}

.search-result-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.search-result-title {
    font-weight: 500;
    color: inherit;
}

.search-result-title mark {
    background: rgba(241, 196, 15, 0.3);
    color: #f1c40f;
    padding: 1px 2px;
    border-radius: 2px;
}

.search-result-path {
    font-size: 0.8rem;
    color: rgba(255, 255, 255, 0.6);
}

.search-no-results {
    padding: 40px 20px;
    text-align: center;
    color: rgba(255, 255, 255, 0.7);
}

.search-no-results i {
    font-size: 2rem;
    margin-bottom: 15px;
    opacity: 0.5;
}

.search-no-results p {
    font-size: 1.1rem;
    margin-bottom: 8px;
}

.search-no-results small {
    font-size: 0.9rem;
    opacity: 0.7;
}

/* Search Suggestions */
.search-suggestions {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: #34495e;
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 0 0 8px 8px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
    z-index: 1000;
    overflow: hidden;
}

.suggestions-header {
    padding: 8px 12px;
    background: rgba(52, 152, 219, 0.1);
    font-size: 0.8rem;
    color: #3498db;
    font-weight: 500;
}

.suggestion-item {
    padding: 8px 12px;
    cursor: pointer;
    transition: background-color 0.2s;
    color: #bdc3c7;
}

.suggestion-item:hover,
.suggestion-item:focus {
    background: rgba(52, 152, 219, 0.2);
    color: #3498db;
    outline: none;
}

/* Bookmark Button Styles */
.bookmark-btn.bookmarked {
    background: #e74c3c;
    color: white;
    border-color: #c0392b;
}

.bookmark-btn.bookmarked:hover {
    background: #c0392b;
    border-color: #a93226;
}

.bookmark-icon {
    color: #e74c3c;
    margin-left: auto;
}

/* Reading Progress Indicator */
.reading-progress-indicator {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 0.85rem;
    color: #7f8c8d;
}

.progress-bar {
    width: 80px;
    height: 6px;
    background: #ecf0f1;
    border-radius: 3px;
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, #3498db, #2ecc71);
    border-radius: 3px;
    transition: width 0.3s ease;
}

.progress-text {
    font-size: 0.8rem;
    color: #95a5a6;
    white-space: nowrap;
}

/* Quick Actions FAB */
.quick-actions-fab {
    position: fixed;
    bottom: 30px;
    right: 30px;
    z-index: 1000;
}

.fab-main {
    width: 56px;
    height: 56px;
    border-radius: 50%;
    background: #3498db;
    color: white;
    border: none;
    cursor: pointer;
    box-shadow: 0 4px 12px rgba(52, 152, 219, 0.4);
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
}

.fab-main:hover {
    background: #2980b9;
    transform: scale(1.1);
    box-shadow: 0 6px 20px rgba(52, 152, 219, 0.6);
}

.fab-main:focus {
    outline: 2px solid #60a5fa;
    outline-offset: 2px;
}

.fab-menu {
    position: absolute;
    bottom: 70px;
    right: 0;
    display: flex;
    flex-direction: column;
    gap: 12px;
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px);
    transition: all 0.3s ease;
}

.quick-actions-fab.open .fab-menu {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.fab-action {
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: #34495e;
    color: white;
    border: none;
    cursor: pointer;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1rem;
}

.fab-action:hover {
    background: #2c3e50;
    transform: scale(1.1);
}

.fab-action:focus {
    outline: 2px solid #60a5fa;
    outline-offset: 2px;
}

/* Modal Styles */
.modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.7);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 2000;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
}

.modal-overlay.show {
    opacity: 1;
    visibility: visible;
}

.modal {
    background: white;
    border-radius: 12px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
    max-width: 600px;
    width: 90vw;
    max-height: 80vh;
    display: flex;
    flex-direction: column;
    transform: scale(0.9) translateY(20px);
    transition: transform 0.3s ease;
}

.modal-overlay.show .modal {
    transform: scale(1) translateY(0);
}

.modal-header {
    padding: 20px 24px;
    border-bottom: 1px solid #ecf0f1;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.modal-header h3 {
    margin: 0;
    color: #2c3e50;
    font-size: 1.3rem;
    font-weight: 600;
}

.modal-close {
    background: none;
    border: none;
    color: #95a5a6;
    cursor: pointer;
    font-size: 1.2rem;
    padding: 4px;
    border-radius: 4px;
    transition: color 0.2s;
}

.modal-close:hover {
    color: #e74c3c;
}

.modal-close:focus {
    outline: 2px solid #3498db;
    outline-offset: 2px;
}

.modal-content {
    padding: 0;
    overflow-y: auto;
    flex: 1;
}

/* Bookmark & History Items */
.bookmark-item,
.history-item {
    padding: 16px 24px;
    border-bottom: 1px solid #ecf0f1;
    display: flex;
    align-items: center;
    gap: 16px;
    transition: background-color 0.2s;
}

.bookmark-item:hover,
.history-item:hover {
    background: #f8f9fa;
}

.bookmark-item:last-child,
.history-item:last-child {
    border-bottom: none;
}

.bookmark-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.bookmark-title,
.history-title {
    color: #2c3e50;
    text-decoration: none;
    font-weight: 500;
    font-size: 1rem;
    transition: color 0.2s;
}

.bookmark-title:hover,
.history-title:hover {
    color: #3498db;
}

.bookmark-meta {
    display: flex;
    gap: 12px;
    font-size: 0.85rem;
    color: #7f8c8d;
}

.bookmark-progress {
    color: #27ae60;
    font-weight: 500;
}

.history-date {
    font-size: 0.85rem;
    color: #95a5a6;
}

.bookmark-remove {
    background: none;
    border: none;
    color: #e74c3c;
    cursor: pointer;
    padding: 8px;
    border-radius: 4px;
    transition: background-color 0.2s;
}

.bookmark-remove:hover {
    background: rgba(231, 76, 60, 0.1);
}

.bookmark-remove:focus {
    outline: 2px solid #3498db;
    outline-offset: 2px;
}

.empty-state {
    padding: 60px 24px;
    text-align: center;
    color: #95a5a6;
}

.empty-state i {
    font-size: 3rem;
    margin-bottom: 20px;
    opacity: 0.5;
}

.empty-state p {
    font-size: 1.1rem;
    margin: 0;
}

/* Notifications */
.notification {
    position: fixed;
    top: 20px;
    right: 20px;
    background: white;
    color: #2c3e50;
    padding: 16px 20px;
    border-radius: 8px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.15);
    display: flex;
    align-items: center;
    gap: 12px;
    z-index: 3000;
    transform: translateX(400px);
    transition: transform 0.3s ease;
    min-width: 300px;
    border-left: 4px solid #3498db;
}

.notification.show {
    transform: translateX(0);
}

.notification-success {
    border-left-color: #27ae60;
}

.notification-success i {
    color: #27ae60;
}

.notification-error {
    border-left-color: #e74c3c;
}

.notification-error i {
    color: #e74c3c;
}

.notification span {
    flex: 1;
    font-size: 0.95rem;
}

.notification-close {
    background: none;
    border: none;
    color: #95a5a6;
    cursor: pointer;
    font-size: 0.9rem;
    padding: 4px;
    border-radius: 4px;
    transition: color 0.2s;
}

.notification-close:hover {
    color: #7f8c8d;
}

.notification-close:focus {
    outline: 2px solid #3498db;
    outline-offset: 2px;
}

/* Print Styles */
@media print {
    .sidebar,
    .toolbar,
    .breadcrumb,
    .tutorial-navigation,
    .tutorial-actions,
    .table-of-contents,
    .quick-actions-fab,
    .notification,
    .modal-overlay {
        display: none !important;
    }
    
    .main-content {
        margin-left: 0 !important;
    }
    
    .content-wrapper {
        max-width: none;
        padding: 0;
        margin: 0;
    }
    
    .markdown-content {
        box-shadow: none;
        border-radius: 0;
        padding: 0;
    }
    
    body {
        background: white !important;
    }
    
    .markdown-content h1,
    .markdown-content h2,
    .markdown-content h3,
    .markdown-content h4,
    .markdown-content h5,
    .markdown-content h6 {
        break-after: avoid;
        page-break-after: avoid;
    }
    
    .markdown-content pre {
        break-inside: avoid;
        page-break-inside: avoid;
    }
    
    .copy-btn {
        display: none !important;
    }
}

/* Dark Theme Enhancements */
.theme-dark .modal {
    background: #0b1220;
    color: #e2e8f0;
}

.theme-dark .modal-header {
    border-color: #1f2937;
}

.theme-dark .modal-header h3 {
    color: #e2e8f0;
}

.theme-dark .bookmark-item,
.theme-dark .history-item {
    border-color: #1f2937;
}

.theme-dark .bookmark-item:hover,
.theme-dark .history-item:hover {
    background: #111827;
}

.theme-dark .bookmark-title,
.theme-dark .history-title {
    color: #e2e8f0;
}

.theme-dark .bookmark-title:hover,
.theme-dark .history-title:hover {
    color: #60a5fa;
}

.theme-dark .notification {
    background: #0b1220;
    color: #e2e8f0;
    border-color: #1f2937;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.5);
}

.theme-dark .search-suggestions {
    background: #0b1220;
    border-color: #1f2937;
}

.theme-dark .suggestion-item {
    color: #e2e8f0;
}

.theme-dark .suggestion-item:hover,
.theme-dark .suggestion-item:focus {
    background: #111827;
    color: #60a5fa;
}

.theme-dark .progress-bar {
    background: #1f2937;
}

/* Mobile Responsive Enhancements */
@media (max-width: 768px) {
    .quick-actions-fab {
        bottom: 20px;
        right: 20px;
    }
    
    .fab-main {
        width: 50px;
        height: 50px;
    }
    
    .fab-action {
        width: 42px;
        height: 42px;
    }
    
    .modal {
        width: 95vw;
        max-height: 90vh;
        margin: 20px;
    }
    
    .notification {
        right: 10px;
        left: 10px;
        min-width: auto;
    }
    
    .reading-progress-indicator {
        flex-direction: column;
        align-items: flex-start;
        gap: 6px;
    }
    
    .progress-bar {
        width: 100px;
    }
}

/* Accessibility Improvements */
@media (prefers-reduced-motion: reduce) {
    .fab-main,
    .fab-action,
    .modal-overlay,
    .modal,
    .notification,
    .progress-fill {
        transition: none;
    }
}

/* Enhanced keyboard shortcuts info */
.keyboard-shortcuts-hint {
    position: fixed;
    bottom: 100px;
    right: 30px;
    background: rgba(0, 0, 0, 0.8);
    color: white;
    padding: 12px 16px;
    border-radius: 8px;
    font-size: 0.85rem;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    z-index: 999;
    max-width: 300px;
}

.keyboard-shortcuts-hint.show {
    opacity: 1;
    visibility: visible;
}

.keyboard-shortcuts-hint h4 {
    margin: 0 0 8px 0;
    font-size: 0.9rem;
    color: #60a5fa;
}

.keyboard-shortcuts-hint ul {
    margin: 0;
    padding: 0;
    list-style: none;
}

.keyboard-shortcuts-hint li {
    margin-bottom: 4px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.keyboard-shortcuts-hint kbd {
    background: #333;
    color: white;
    padding: 2px 6px;
    border-radius: 3px;
    font-size: 0.75rem;
    font-family: monospace;
}

/* Enhanced tooltip system */
.tooltip {
    position: relative;
}

.tooltip::before {
    content: attr(data-tooltip);
    position: absolute;
    bottom: 100%;
    left: 50%;
    transform: translateX(-50%);
    background: rgba(0, 0, 0, 0.8);
    color: white;
    padding: 6px 10px;
    border-radius: 4px;
    font-size: 0.8rem;
    white-space: nowrap;
    opacity: 0;
    visibility: hidden;
    transition: all 0.2s ease;
    z-index: 1000;
    pointer-events: none;
}

.tooltip::after {
    content: '';
    position: absolute;
    bottom: calc(100% - 6px);
    left: 50%;
    transform: translateX(-50%);
    border: 6px solid transparent;
    border-top-color: rgba(0, 0, 0, 0.8);
    opacity: 0;
    visibility: hidden;
    transition: all 0.2s ease;
    z-index: 1000;
    pointer-events: none;
}

.tooltip:hover::before,
.tooltip:hover::after {
    opacity: 1;
    visibility: visible;
}

/* Mobile responsive improvements for new features */
@media (max-width: 768px) {
    .keyboard-shortcuts-hint {
        bottom: 80px;
        right: 10px;
        left: 10px;
        max-width: none;
    }
    
    .tutorial-actions {
        flex-direction: column;
        align-items: stretch;
        gap: 12px;
    }
}

/* Keyboard Shortcuts Modal */
.shortcuts-grid {
    display: grid;
    gap: 12px;
    padding: 20px;
}

.shortcut-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 12px 16px;
    background: #f8f9fa;
    border-radius: 8px;
    border-left: 3px solid #3498db;
}

.shortcut-item kbd {
    background: #2c3e50;
    color: white;
    padding: 6px 12px;
    border-radius: 6px;
    font-family: -apple-system, BlinkMacSystemFont, 'SF Mono', 'Monaco', 'Inconsolata', 'Fira Code', 'Droid Sans Mono', 'Source Code Pro', monospace;
    font-size: 0.85rem;
    font-weight: 500;
    letter-spacing: 0.5px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.shortcut-item span {
    color: #2c3e50;
    font-weight: 500;
}

.theme-dark .shortcut-item {
    background: #111827;
    border-left-color: #60a5fa;
}

.theme-dark .shortcut-item span {
    color: #e2e8f0;
}

.theme-dark .shortcut-item kbd {
    background: #374151;
    color: #e2e8f0;
}

/* Enhanced Focus Styles */
*:focus-visible {
    outline: 2px solid #3498db;
    outline-offset: 2px;
    border-radius: 4px;
}

/* Loading states and skeleton screens */
.skeleton {
    background: linear-gradient(90deg, #f0f0f0 25%, #e0e0e0 50%, #f0f0f0 75%);
    background-size: 200% 100%;
    animation: loading 1.5s infinite;
}

@keyframes loading {
    0% { background-position: 200% 0; }
    100% { background-position: -200% 0; }
}

.skeleton-text {
    height: 1rem;
    margin-bottom: 0.5rem;
    border-radius: 4px;
}

.skeleton-title {
    height: 1.5rem;
    width: 60%;
    margin-bottom: 1rem;
    border-radius: 4px;
}

.skeleton-paragraph {
    height: 0.875rem;
    margin-bottom: 0.75rem;
    border-radius: 4px;
}

.skeleton-paragraph:last-child {
    width: 80%;
}

.theme-dark .skeleton {
    background: linear-gradient(90deg, #1f2937 25%, #374151 50%, #1f2937 75%);
    background-size: 200% 100%;
}

/* Smooth scroll behavior for better UX */
html {
    scroll-behavior: smooth;
}

/* Article layout with right-rail ToC like GitHub */
.article-layout {
    display: grid;
    grid-template-columns: minmax(0, 1fr) 320px;
    gap: 32px;
    align-items: start;
}

.article-layout .markdown-content {
    order: 1;
}

.article-layout .table-of-contents {
    order: 2;
    position: sticky;
    top: 72px; /* below toolbar */
    max-height: calc(100vh - 90px);
    overflow: auto;
    z-index: 10; /* above scaled content and copy buttons */
}

/* Give markdown a little breathing room from the ToC */
.article-layout .markdown-content {
    padding-right: 24px;
}

/* Collapse ToC below on small screens */
@media (max-width: 1024px) {
    .article-layout {
        grid-template-columns: 1fr;
    }
    /* Keep ToC sticky even on narrower screens; place above content but sticky */
    .article-layout .table-of-contents {
        position: sticky;
        top: 72px;
        max-height: calc(100vh - 90px);
        order: 0;
        z-index: 5;
    }
}

/* Dark theme active state */
.theme-dark .toc-link.active {
    background: #111827;
    color: #e2e8f0;
    border-left-color: #60a5fa;
}

/* High contrast mode support */
@media (prefers-contrast: high) {
    .btn-secondary,
    .tb-btn,
    .fab-main,
    .fab-action {
        border: 2px solid currentColor;
    }
    
    .notification {
        border: 2px solid;
    }
}

/* Reduced transparency for better readability */
@media (prefers-reduced-transparency) {
    .modal-overlay {
        background: #000;
    }
    
    .search-suggestions,
    .notification,
    .quick-actions-fab {
        backdrop-filter: none;
    }
}

/* Floating Donate Button */
.donate-fab {
    position: fixed;
    bottom: 24px;
    left: 24px;
    z-index: 1200;
}

.donate-btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: #ffc439; /* PayPal yellow */
    color: #1d1f20;
    text-decoration: none;
    padding: 10px 14px;
    border-radius: 999px;
    font-weight: 600;
    border: 1px solid rgba(0,0,0,0.1);
    box-shadow: 0 6px 16px rgba(0,0,0,0.15);
    transition: transform 0.15s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.donate-btn i {
    color: #003087; /* PayPal blue */
    font-size: 1.1rem;
}

.donate-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 22px rgba(0,0,0,0.2);
}

.donate-btn:active {
    transform: translateY(0);
}

/* Dark theme variant */
.theme-dark .donate-btn {
    background: #ffd766;
    color: #0b1220;
    border-color: #1f2937;
}

@media (max-width: 768px) {
    .donate-fab { bottom: 16px; left: 16px; }
    .donate-btn { padding: 10px 12px; }
}

/* Footer */
.site-footer {
    border-top: 1px solid #e1e8ed;
    background: #fff;
}
.site-footer .footer-inner {
    max-width: 1320px;
    margin: 0 auto;
    padding: 16px 30px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    color: #64748b;
}
.site-footer a.footer-link { color: #3498db; text-decoration: none; }
.site-footer a.footer-link:hover { text-decoration: underline; }
.theme-dark .site-footer { background: #0b1220; border-color: #1f2937; }
.theme-dark .site-footer .footer-inner { color: #94a3b8; }

/* Cookie consent */
.cookie-consent {
    position: fixed;
    inset: auto 16px 16px 16px;
    background: #ffffff;
    border: 1px solid #e2e8f0;
    box-shadow: 0 8px 24px rgba(0,0,0,0.12);
    border-radius: 12px;
    padding: 14px;
    z-index: 3000;
    display: none;
}
.cookie-consent.show { display: block; }
.cookie-consent .cookie-consent-content { display: flex; gap: 12px; align-items: center; }
.cookie-consent .cookie-text { flex: 1; font-size: 0.95rem; color: #334155; }
.cookie-consent .cookie-text a { color: #3498db; }
.cookie-consent .cookie-actions { display: flex; gap: 8px; }
.theme-dark .cookie-consent { background: #0b1220; border-color: #1f2937; color: #e2e8f0; }
.theme-dark .cookie-consent .cookie-text { color: #cbd5e1; }

/* Cookie preferences items */
.cookie-opt-group { display: grid; gap: 10px; }
.cookie-opt { display: flex; align-items: center; gap: 10px; padding: 10px; border: 1px solid #e2e8f0; border-radius: 8px; }
.cookie-opt small { display: block; color: #64748b; }
.theme-dark .cookie-opt { border-color: #1f2937; }