/* Microsoft 365 Copilot Training - Main Styles */

:root {
    /* Light theme colors */
    --bg-primary: #ffffff;
    --bg-secondary: #f5f5f5;
    --bg-tertiary: #e8e8e8;
    --text-primary: #242424;
    --text-secondary: #666666;
    --text-tertiary: #999999;
    --accent-primary: #0078d4;
    --accent-hover: #106ebe;
    --accent-light: #e6f2fa;
    --accent-secondary: #6264a7;  /* Microsoft Teams purple - good contrast on white */
    --border-color: #d1d1d1;
    --success: #107c10;
    --warning: #ff8c00;
    --error: #d13438;

    /* Layout */
    --sidebar-width: 280px;
    --header-height: 120px;

    /* Spacing */
    --space-xs: 4px;
    --space-sm: 8px;
    --space-md: 16px;
    --space-lg: 24px;
    --space-xl: 32px;

    /* Border radius */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;

    /* Shadows */
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.1);
    --shadow-md: 0 4px 6px rgba(0,0,0,0.1);
    --shadow-lg: 0 10px 20px rgba(0,0,0,0.15);

    /* Typography */
    --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    --font-mono: 'Consolas', 'Monaco', 'Courier New', monospace;
}

/* Dark theme */
[data-theme="dark"] {
    --bg-primary: #1e1e1e;
    --bg-secondary: #2d2d2d;
    --bg-tertiary: #3d3d3d;
    --text-primary: #e8e8e8;
    --text-secondary: #b3b3b3;
    --text-tertiary: #808080;
    --accent-primary: #4a9eff;
    --accent-hover: #6bb0ff;
    --accent-light: #1e3a5f;
    --accent-secondary: #8b8cd9;  /* Lighter purple for dark backgrounds */
    --border-color: #3d3d3d;
}

/* High contrast mode support */
@media (prefers-contrast: high) {
    :root {
        --border-color: #000000;
        --text-secondary: #000000;
    }
    [data-theme="dark"] {
        --border-color: #ffffff;
        --text-secondary: #ffffff;
    }
}

/* Base reset */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family);
    color: var(--text-primary);
    background-color: var(--bg-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

/* ===========================================
   Custom Scrollbars
   =========================================== */

/* Webkit browsers (Chrome, Safari, Edge) */
::-webkit-scrollbar {
    width: 10px;
    height: 10px;
}

::-webkit-scrollbar-track {
    background: var(--bg-secondary);
    border-radius: 0;
}

::-webkit-scrollbar-thumb {
    background: linear-gradient(180deg, var(--accent-primary), var(--accent-secondary));
    border-radius: 5px;
    border: 2px solid var(--bg-secondary);
}

::-webkit-scrollbar-thumb:hover {
    background: linear-gradient(180deg, var(--accent-secondary), var(--accent-primary));
}

::-webkit-scrollbar-corner {
    background: var(--bg-secondary);
}

/* Firefox */
* {
    scrollbar-width: thin;
    scrollbar-color: var(--accent-primary) var(--bg-secondary);
}

/* Skip to main content for screen readers */
.skip-link {
    position: absolute;
    top: -40px;
    left: 0;
    background: var(--accent-primary);
    color: white;
    padding: var(--space-sm);
    z-index: 100;
}

.skip-link:focus {
    top: 0;
}

/* App container */
.app-container {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* Header */
.app-header {
    position: sticky;
    top: 0;
    z-index: 50;
    background-color: var(--bg-primary);
    border-bottom: 1px solid var(--border-color);
    box-shadow: var(--shadow-sm);
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--space-lg);
}

.header-content h1 {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-primary);
}

.header-actions {
    display: flex;
    gap: var(--space-md);
    align-items: center;
}

/* Progress bar */
.progress-bar {
    height: 4px;
    background-color: var(--bg-tertiary);
}

.progress-fill {
    height: 100%;
    background-color: var(--success);
    transition: width 0.3s ease;
    width: 0%;
}

/* Search panel */
.search-panel {
    padding: var(--space-md) var(--space-lg);
    background-color: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
}

.search-panel.hidden {
    display: none;
}

#search-input {
    width: 100%;
    padding: var(--space-md);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 1rem;
    background-color: var(--bg-primary);
    color: var(--text-primary);
}

#search-results {
    margin-top: var(--space-md);
    max-height: 300px;
    overflow-y: auto;
}

/* Main content area */
.main-content {
    display: flex;
    flex: 1;
    position: relative;
}

/* Sidebar */
.sidebar {
    width: var(--sidebar-width);
    background-color: var(--bg-secondary);
    border-right: 1px solid var(--border-color);
    overflow-y: auto;
    position: sticky;
    top: var(--header-height);
    height: calc(100vh - var(--header-height));
}

.sidebar-nav {
    padding: var(--space-lg);
}

.module {
    margin-bottom: var(--space-lg);
}

.module-title {
    font-size: 0.875rem;
    font-weight: 600;
    text-transform: uppercase;
    color: var(--text-secondary);
    margin-bottom: var(--space-md);
    padding: var(--space-sm) 0;
}

.lesson-list {
    list-style: none;
}

.lesson-item {
    margin-bottom: var(--space-xs);
}

.lesson-link {
    display: flex;
    align-items: center;
    padding: var(--space-sm) var(--space-md);
    color: var(--text-primary);
    text-decoration: none;
    border-radius: var(--radius-sm);
    transition: background-color 0.2s;
}

.lesson-link:hover {
    background-color: var(--bg-tertiary);
}

.lesson-link.active {
    background-color: var(--accent-light);
    color: var(--accent-primary);
    font-weight: 500;
}

.lesson-link .checkmark {
    margin-left: auto;
    color: var(--success);
    display: none;
}

.lesson-link.completed .checkmark {
    display: block;
}

/* Lesson content */
.lesson-content {
    flex: 1;
    padding: var(--space-xl);
    padding-right: var(--space-md); /* Reduced right padding for scrollbar at edge */
    max-width: none; /* Allow full width */
    position: relative;
    overflow-y: auto;
    height: calc(100vh - var(--header-height));
}

/* Inner container for max-width content */
.lesson-article {
    max-width: 850px;
}

.breadcrumbs {
    font-size: 0.875rem;
    color: var(--text-secondary);
    margin-bottom: var(--space-lg);
}

.breadcrumbs a {
    color: var(--accent-primary);
    text-decoration: none;
}

.breadcrumbs a:hover {
    text-decoration: underline;
}

.lesson-article h1 {
    font-size: 2.25rem;
    font-weight: 600;
    margin-bottom: var(--space-md);
    color: var(--text-primary);
}

.lesson-article h2 {
    font-size: 1.75rem;
    font-weight: 600;
    margin-top: var(--space-xl);
    margin-bottom: var(--space-md);
    color: var(--text-primary);
}

.lesson-article h3 {
    font-size: 1.375rem;
    font-weight: 600;
    margin-top: var(--space-lg);
    margin-bottom: var(--space-md);
    color: var(--text-primary);
}

.lesson-article p {
    margin-bottom: var(--space-md);
    color: var(--text-primary);
}

.lesson-article ul,
.lesson-article ol {
    margin-bottom: var(--space-md);
    padding-left: var(--space-xl);
}

.lesson-article li {
    margin-bottom: var(--space-sm);
}

.lesson-article code {
    background-color: var(--bg-secondary);
    padding: 2px 6px;
    border-radius: var(--radius-sm);
    font-family: var(--font-mono);
    font-size: 0.875em;
}

.lesson-article pre {
    background-color: var(--bg-secondary);
    padding: var(--space-md);
    border-radius: var(--radius-md);
    overflow-x: auto;
    margin-bottom: var(--space-md);
}

.lesson-article pre code {
    background-color: transparent;
    padding: 0;
}

/* Video container */
.video-container {
    margin: var(--space-xl) 0;
    border-radius: var(--radius-md);
    overflow: hidden;
    background-color: var(--bg-secondary);
}

.video-container video {
    width: 100%;
    display: block;
}

/* Info boxes */
.info-box {
    padding: var(--space-md);
    border-radius: var(--radius-md);
    margin: var(--space-lg) 0;
    border-left: 4px solid var(--accent-primary);
    background-color: var(--accent-light);
}

.info-box.warning {
    border-left-color: var(--warning);
    background-color: #fff4e5;
}

.info-box.error {
    border-left-color: var(--error);
    background-color: #fde7e9;
}

.info-box.success {
    border-left-color: var(--success);
    background-color: #e6f7e6;
}

/* Lesson actions */
.lesson-actions {
    display: flex;
    gap: var(--space-md);
    margin-top: var(--space-xl);
    padding-top: var(--space-lg);
    border-top: 1px solid var(--border-color);
}

/* Buttons */
.btn-primary,
.btn-secondary,
.btn-icon {
    padding: var(--space-sm) var(--space-md);
    border: none;
    border-radius: var(--radius-md);
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
}

.btn-primary {
    background-color: var(--accent-primary);
    color: white;
}

.btn-primary:hover {
    background-color: var(--accent-hover);
}

.btn-secondary {
    background-color: var(--bg-tertiary);
    color: var(--text-primary);
}

.btn-secondary:hover {
    background-color: var(--border-color);
}

.btn-logout {
    background-color: transparent;
    color: var(--text-secondary);
    border: 1px solid var(--border-color);
}

.btn-logout:hover {
    background-color: var(--error);
    color: white;
    border-color: var(--error);
}

.btn-icon {
    padding: var(--space-sm);
    background-color: transparent;
}

.btn-icon:hover {
    background-color: var(--bg-tertiary);
}

/* Modals */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 100;
}

.modal.hidden {
    display: none;
}

.modal-content {
    background-color: var(--bg-primary);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    max-width: 600px;
    width: 90%;
    max-height: 90vh;
    display: flex;
    flex-direction: column;
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--space-lg);
    border-bottom: 1px solid var(--border-color);
}

.modal-header h2 {
    font-size: 1.375rem;
    font-weight: 600;
}

.modal-close {
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--text-secondary);
    padding: 0;
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.modal-close:hover {
    color: var(--text-primary);
}

.modal-body {
    padding: var(--space-lg);
    overflow-y: auto;
    flex: 1;
}

.modal-footer {
    padding: var(--space-lg);
    border-top: 1px solid var(--border-color);
    display: flex;
    gap: var(--space-md);
    justify-content: flex-end;
}

/* Welcome screen */
.welcome-screen {
    text-align: center;
    padding: var(--space-xl) 0;
}

.welcome-screen h2 {
    font-size: 2rem;
    margin-bottom: var(--space-lg);
}

.course-overview {
    max-width: 600px;
    margin: var(--space-xl) auto;
    text-align: left;
    background-color: var(--bg-secondary);
    padding: var(--space-xl);
    border-radius: var(--radius-lg);
}

.course-overview h3 {
    margin-bottom: var(--space-md);
}

.course-overview ul {
    list-style-position: inside;
}

/* Utility classes */
.hidden {
    display: none !important;
}

/* Focus styles for accessibility */
*:focus-visible {
    outline: 2px solid var(--accent-primary);
    outline-offset: 2px;
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }
}

/* ===========================================
   Video Modal Component
   =========================================== */

.video-modal .modal-content {
    max-width: 900px;
    width: 95%;
}

/* YouTube iframe container */
.video-iframe-container {
    position: relative;
    width: 100%;
    padding-bottom: 56.25%; /* 16:9 aspect ratio */
    height: 0;
    overflow: hidden;
    border-radius: var(--radius-md);
    background-color: #000;
}

.video-iframe-container iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border: none;
}

.video-modal-body {
    text-align: center;
    padding: var(--space-xl) var(--space-lg);
}

.video-modal-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto var(--space-lg);
    background: linear-gradient(135deg, var(--accent-primary), #6264a7);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2.5rem;
    color: white;
    box-shadow: var(--shadow-md);
}

.video-modal-title {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: var(--space-md);
    color: var(--text-primary);
}

.video-modal-description {
    font-size: 1rem;
    color: var(--text-secondary);
    margin-bottom: var(--space-xl);
    line-height: 1.6;
    max-width: 500px;
    margin-left: auto;
    margin-right: auto;
}

.video-modal-duration {
    display: inline-flex;
    align-items: center;
    gap: var(--space-sm);
    font-size: 0.875rem;
    color: var(--text-tertiary);
    margin-bottom: var(--space-xl);
    padding: var(--space-sm) var(--space-md);
    background-color: var(--bg-secondary);
    border-radius: var(--radius-md);
}

.video-open-btn {
    display: inline-flex;
    align-items: center;
    gap: var(--space-md);
    font-size: 1.125rem;
    font-weight: 600;
    padding: var(--space-md) var(--space-xl);
    background: linear-gradient(135deg, var(--accent-primary), #106ebe);
    color: white;
    border: none;
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: var(--shadow-md);
    text-decoration: none;
}

.video-open-btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
    background: linear-gradient(135deg, #106ebe, #0078d4);
}

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

.video-open-btn-icon {
    font-size: 1.5rem;
}

.video-modal-source {
    margin-top: var(--space-lg);
    font-size: 0.75rem;
    color: var(--text-tertiary);
}

.video-modal-source a {
    color: var(--accent-primary);
    text-decoration: none;
}

.video-modal-source a:hover {
    text-decoration: underline;
}

/* Watch Video Button (for use in lessons) */
.btn-video {
    display: inline-flex;
    align-items: center;
    gap: var(--space-sm);
    padding: var(--space-md) var(--space-lg);
    background-color: var(--bg-secondary);
    color: var(--text-primary);
    border: 2px solid var(--accent-primary);
    border-radius: var(--radius-md);
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s ease;
}

.btn-video:hover {
    background-color: var(--accent-primary);
    color: white;
}

.btn-video-icon {
    font-size: 1.25rem;
}

/* Lesson Images */
.lesson-image {
    margin: var(--space-xl) 0;
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.lesson-image img {
    width: 100%;
    height: auto;
    display: block;
}

.lesson-image figcaption {
    padding: var(--space-md) var(--space-lg);
    font-size: 0.875rem;
    color: var(--text-secondary);
    border-top: 1px solid var(--border-color);
}

.lesson-image figcaption strong {
    color: var(--text-primary);
}

.image-source {
    display: block;
    margin-top: var(--space-xs);
    font-size: 0.75rem;
    color: var(--text-tertiary);
    font-style: italic;
}

/* Video Cards */
.video-card {
    margin: var(--space-lg) 0;
    padding: var(--space-lg);
    background: linear-gradient(135deg, var(--bg-secondary) 0%, var(--bg-tertiary) 100%);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-color);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.video-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.12);
}

.video-card.external {
    border-left: 4px solid var(--accent-secondary);
}

.btn-video-external {
    display: inline-flex;
    align-items: center;
    gap: var(--space-sm);
    padding: var(--space-md) var(--space-lg);
    background-color: var(--accent-secondary);
    color: white;
    border: none;
    border-radius: var(--radius-md);
    font-size: 1rem;
    font-weight: 500;
    text-decoration: none;
    cursor: pointer;
    transition: all 0.2s ease;
}

.btn-video-external:hover {
    background-color: var(--success);
    transform: scale(1.02);
}

.video-description {
    margin-top: var(--space-md);
    font-size: 0.875rem;
    color: var(--text-secondary);
    line-height: 1.5;
}

/* App Cards Grid (for introduction) */
.app-cards-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: var(--space-md);
    margin: var(--space-lg) 0;
}

.app-card {
    background: var(--bg-secondary);
    border-radius: var(--radius-md);
    overflow: hidden;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
    transition: transform 0.2s ease;
}

.app-card:hover {
    transform: translateY(-4px);
}

.app-card img {
    width: 100%;
    height: auto;
    display: block;
}

/* ===========================================
   Interactive LMS Components
   =========================================== */

/* ===========================================
   1. Flip Cards
   =========================================== */

.flip-card-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--space-lg);
    margin: var(--space-xl) 0;
}

.flip-card {
    perspective: 1000px;
    height: 200px;
    cursor: pointer;
    position: relative;
}

.flip-card-inner {
    position: relative;
    width: 100%;
    height: 100%;
    transition: transform 0.6s cubic-bezier(0.4, 0, 0.2, 1);
    transform-style: preserve-3d;
}

.flip-card.flipped .flip-card-inner {
    transform: rotateY(180deg);
}

.flip-card:focus .flip-card-inner {
    outline: none;
}

.flip-card:focus-visible {
    outline: 2px solid var(--accent-primary);
    outline-offset: 4px;
    border-radius: var(--radius-lg);
}

.flip-card-front,
.flip-card-back {
    position: absolute;
    width: 100%;
    height: 100%;
    backface-visibility: hidden;
    -webkit-backface-visibility: hidden;
    border-radius: var(--radius-lg);
    padding: var(--space-lg);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.15);
    transition: box-shadow 0.3s ease;
}

.flip-card:hover .flip-card-front,
.flip-card:hover .flip-card-back {
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.2);
}

.flip-card-front {
    background: linear-gradient(135deg, var(--accent-primary) 0%, var(--accent-secondary) 100%);
    color: white;
}

.flip-card-front h4 {
    font-size: 1.1rem;
    font-weight: 600;
    margin: 0 0 var(--space-sm) 0;
    line-height: 1.4;
}

.flip-card-front p {
    font-size: 0.85rem;
    margin: 0;
    opacity: 0.9;
}

/* Flip indicator icon */
.flip-card-front::after {
    content: '↻';
    position: absolute;
    bottom: var(--space-md);
    right: var(--space-md);
    width: 28px;
    height: 28px;
    background: rgba(255, 255, 255, 0.25);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.9rem;
    font-weight: bold;
    transition: all 0.3s ease;
}

.flip-card:hover .flip-card-front::after {
    background: rgba(255, 255, 255, 0.4);
    transform: rotate(180deg);
}

.flip-card.flipped .flip-card-front::after {
    transform: rotate(360deg);
}

.flip-card-back {
    background: var(--bg-secondary);
    color: var(--text-primary);
    transform: rotateY(180deg);
    border: 2px solid var(--accent-primary);
    padding: var(--space-md);
}

.flip-card-back p {
    font-size: 0.9rem;
    line-height: 1.5;
    margin: 0;
}

.flip-card-back ol,
.flip-card-back ul {
    margin: 0;
    padding-left: var(--space-lg);
    text-align: left;
}

.flip-card-back li {
    font-size: 0.85rem;
    margin-bottom: var(--space-xs);
}

/* Back flip indicator */
.flip-card-back::after {
    content: '↻';
    position: absolute;
    bottom: var(--space-md);
    right: var(--space-md);
    width: 28px;
    height: 28px;
    background: var(--accent-light);
    color: var(--accent-primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.9rem;
    font-weight: bold;
    transition: all 0.3s ease;
}

.flip-card:hover .flip-card-back::after {
    background: var(--accent-primary);
    color: white;
    transform: rotate(-180deg);
}

/* Flip card color variants */
.flip-card.warning .flip-card-front {
    background: linear-gradient(135deg, var(--warning), #e67300);
}

.flip-card.warning .flip-card-back {
    border-color: var(--warning);
}

.flip-card.warning .flip-card-back::after {
    color: var(--warning);
}

.flip-card.success .flip-card-front {
    background: linear-gradient(135deg, var(--success), #0a5a0a);
}

.flip-card.success .flip-card-back {
    border-color: var(--success);
}

.flip-card.success .flip-card-back::after {
    color: var(--success);
}

/* ===========================================
   2. Enhanced Accordions
   =========================================== */

.accordion {
    margin: var(--space-lg) 0;
    border-radius: var(--radius-md);
    overflow: hidden;
    border: 1px solid var(--border-color);
}

.accordion-item {
    border-bottom: 1px solid var(--border-color);
}

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

.accordion-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--space-md) var(--space-lg);
    background: var(--bg-secondary);
    cursor: pointer;
    transition: background-color 0.2s ease;
    user-select: none;
}

.accordion-header:hover {
    background: var(--bg-tertiary);
}

.accordion-header h4 {
    margin: 0;
    font-size: 1rem;
    font-weight: 500;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: var(--space-sm);
}

.accordion-icon {
    font-size: 1.25rem;
    transition: transform 0.3s ease;
    color: var(--accent-primary);
}

.accordion-item.open .accordion-icon {
    transform: rotate(180deg);
}

.accordion-content {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease, padding 0.3s ease;
    background: var(--bg-primary);
}

.accordion-item.open .accordion-content {
    max-height: 1000px;
    padding: var(--space-lg);
}

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

/* ===========================================
   3. Tabbed Content
   =========================================== */

.tabs-container {
    margin: var(--space-xl) 0;
    border-radius: var(--radius-lg);
    overflow: hidden;
    border: 1px solid var(--border-color);
}

.tabs-nav {
    display: flex;
    background: var(--bg-secondary);
    border-bottom: 2px solid var(--border-color);
    overflow-x: auto;
    scrollbar-width: thin;
}

.tab-btn {
    flex: 1;
    min-width: 120px;
    padding: var(--space-md) var(--space-lg);
    background: transparent;
    border: none;
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--text-secondary);
    cursor: pointer;
    transition: all 0.2s ease;
    position: relative;
    white-space: nowrap;
}

.tab-btn:hover {
    color: var(--accent-primary);
    background: var(--bg-tertiary);
}

.tab-btn.active {
    color: var(--accent-primary);
    background: var(--bg-primary);
}

.tab-btn.active::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--accent-primary);
}

.tab-btn .tab-icon {
    margin-right: var(--space-sm);
}

.tabs-content {
    padding: var(--space-lg);
    background: var(--bg-primary);
}

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

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

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

/* ===========================================
   4. Inline Knowledge Checks
   =========================================== */

.knowledge-check {
    margin: var(--space-xl) 0;
    padding: var(--space-lg);
    background: linear-gradient(135deg, var(--bg-secondary) 0%, var(--bg-tertiary) 100%);
    border-radius: var(--radius-lg);
    border-left: 4px solid var(--accent-secondary);
}

.knowledge-check-header {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    margin-bottom: var(--space-md);
}

.knowledge-check-header .check-icon {
    font-size: 1.5rem;
}

.knowledge-check-header h4 {
    margin: 0;
    font-size: 1rem;
    font-weight: 600;
    color: var(--accent-secondary);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.knowledge-check-question {
    font-size: 1.1rem;
    font-weight: 500;
    color: var(--text-primary);
    margin-bottom: var(--space-lg);
    line-height: 1.5;
}

.knowledge-check-options {
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
}

.knowledge-check-option {
    display: flex;
    align-items: center;
    padding: var(--space-md);
    background: var(--bg-primary);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all 0.2s ease;
}

.knowledge-check-option:hover:not(.disabled) {
    border-color: var(--accent-primary);
    background: var(--accent-light);
}

.knowledge-check-option.selected {
    border-color: var(--accent-primary);
    background: var(--accent-light);
}

.knowledge-check-option.correct {
    border-color: var(--success);
    background: #e6f7e6;
}

.knowledge-check-option.incorrect {
    border-color: var(--error);
    background: #fde7e9;
}

.knowledge-check-option.disabled {
    cursor: default;
    opacity: 0.7;
}

.knowledge-check-option input[type="radio"] {
    display: none;
}

.option-indicator {
    width: 24px;
    height: 24px;
    border: 2px solid var(--border-color);
    border-radius: 50%;
    margin-right: var(--space-md);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    transition: all 0.2s ease;
}

.knowledge-check-option.selected .option-indicator {
    border-color: var(--accent-primary);
    background: var(--accent-primary);
    color: white;
}

.knowledge-check-option.correct .option-indicator {
    border-color: var(--success);
    background: var(--success);
    color: white;
}

.knowledge-check-option.incorrect .option-indicator {
    border-color: var(--error);
    background: var(--error);
    color: white;
}

.option-text {
    flex: 1;
    font-size: 0.95rem;
    color: var(--text-primary);
}

.knowledge-check-feedback {
    margin-top: var(--space-lg);
    padding: var(--space-md);
    border-radius: var(--radius-md);
    display: none;
}

.knowledge-check-feedback.show {
    display: block;
    animation: slideDown 0.3s ease;
}

.knowledge-check-feedback.correct {
    background: #e6f7e6;
    border-left: 4px solid var(--success);
}

.knowledge-check-feedback.incorrect {
    background: #fde7e9;
    border-left: 4px solid var(--error);
}

.knowledge-check-feedback h5 {
    margin: 0 0 var(--space-sm) 0;
    display: flex;
    align-items: center;
    gap: var(--space-sm);
}

.knowledge-check-feedback.correct h5 {
    color: var(--success);
}

.knowledge-check-feedback.incorrect h5 {
    color: var(--error);
}

.knowledge-check-feedback p {
    margin: 0;
    color: var(--text-primary);
    font-size: 0.9rem;
}

@keyframes slideDown {
    from { opacity: 0; transform: translateY(-10px); }
    to { opacity: 1; transform: translateY(0); }
}

/* ===========================================
   5. Interactive Checklists
   =========================================== */

.interactive-checklist {
    margin: var(--space-xl) 0;
    padding: var(--space-lg);
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow-sm);
}

.interactive-checklist h3,
.interactive-checklist h4 {
    margin: 0 0 var(--space-md) 0;
    color: var(--accent-primary);
}

/* Checkbox-based format */
.interactive-checklist ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

.interactive-checklist li {
    display: flex;
    align-items: flex-start;
    gap: var(--space-md);
    padding: var(--space-md);
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    margin-bottom: var(--space-sm);
    transition: all 0.2s ease;
    cursor: pointer;
}

.interactive-checklist li:hover {
    border-color: var(--accent-primary);
}

.interactive-checklist li.completed {
    background: #e6f7e6;
    border-color: var(--success);
}

.interactive-checklist input[type="checkbox"] {
    width: 20px;
    height: 20px;
    margin: 0;
    cursor: pointer;
    accent-color: var(--accent-primary);
    flex-shrink: 0;
}

.interactive-checklist label {
    cursor: pointer;
    flex-grow: 1;
    line-height: 1.5;
    color: var(--text-primary);
}

.interactive-checklist li.completed label {
    text-decoration: line-through;
    color: var(--text-secondary);
}

.interactive-checklist .progress-text {
    text-align: center;
    margin-top: var(--space-lg);
    padding-top: var(--space-md);
    border-top: 1px solid var(--border-color);
    font-weight: 500;
    color: var(--text-secondary);
}

.checklist-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: var(--space-lg);
    padding-bottom: var(--space-md);
    border-bottom: 1px solid var(--border-color);
}

.checklist-header h4 {
    margin: 0;
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: var(--space-sm);
}

.checklist-progress {
    font-size: 0.875rem;
    color: var(--text-secondary);
    font-weight: 500;
}

.checklist-progress .progress-count {
    color: var(--success);
    font-weight: 600;
}

.checklist-items {
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
}

.checklist-item {
    display: flex;
    align-items: flex-start;
    padding: var(--space-md);
    background: var(--bg-primary);
    border-radius: var(--radius-md);
    border: 1px solid var(--border-color);
    cursor: pointer;
    transition: all 0.2s ease;
}

.checklist-item:hover {
    border-color: var(--accent-primary);
}

.checklist-item.checked {
    background: #e6f7e6;
    border-color: var(--success);
}

.checklist-item.checked .item-text {
    text-decoration: line-through;
    color: var(--text-secondary);
}

.item-checkbox {
    width: 22px;
    height: 22px;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-sm);
    margin-right: var(--space-md);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    transition: all 0.2s ease;
}

.checklist-item.checked .item-checkbox {
    background: var(--success);
    border-color: var(--success);
    color: white;
}

.item-content {
    flex: 1;
}

.item-text {
    font-size: 0.95rem;
    color: var(--text-primary);
    margin-bottom: var(--space-xs);
}

.item-description {
    font-size: 0.8rem;
    color: var(--text-secondary);
    margin: 0;
}

.checklist-reset {
    margin-top: var(--space-md);
    padding: var(--space-sm) var(--space-md);
    background: transparent;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 0.8rem;
    color: var(--text-secondary);
    cursor: pointer;
    transition: all 0.2s ease;
}

.checklist-reset:hover {
    border-color: var(--accent-primary);
    color: var(--accent-primary);
}

/* ===========================================
   6. Tooltips / Glossary
   =========================================== */

.glossary-term {
    position: relative;
    display: inline;
    border-bottom: 2px dotted var(--accent-primary);
    color: var(--accent-primary);
    cursor: help;
    font-weight: 500;
}

.glossary-term:hover .tooltip,
.glossary-term:focus .tooltip {
    opacity: 1;
    visibility: visible;
    transform: translateX(-50%) translateY(0);
}

.tooltip {
    position: absolute;
    bottom: calc(100% + 10px);
    left: 50%;
    transform: translateX(-50%) translateY(5px);
    width: 280px;
    padding: var(--space-md);
    background: var(--bg-tertiary);
    color: var(--text-primary);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-lg);
    font-size: 0.875rem;
    line-height: 1.5;
    font-weight: 400;
    opacity: 0;
    visibility: hidden;
    transition: all 0.2s ease;
    z-index: 100;
    pointer-events: none;
}

.tooltip::after {
    content: '';
    position: absolute;
    top: 100%;
    left: 50%;
    transform: translateX(-50%);
    border: 8px solid transparent;
    border-top-color: var(--bg-tertiary);
}

.tooltip-title {
    font-weight: 600;
    color: var(--accent-primary);
    margin-bottom: var(--space-xs);
    display: block;
}

/* Dark mode tooltip adjustments */
[data-theme="dark"] .tooltip {
    background: var(--bg-tertiary);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.4);
}

[data-theme="dark"] .tooltip::after {
    border-top-color: var(--bg-tertiary);
}

/* ===========================================
   7. Timeline / Stepper
   =========================================== */

.timeline {
    margin: var(--space-xl) 0;
    position: relative;
    padding-left: var(--space-xl);
}

.timeline::before {
    content: '';
    position: absolute;
    left: 12px;
    top: 0;
    bottom: 0;
    width: 3px;
    background: linear-gradient(to bottom, var(--accent-primary), var(--accent-secondary));
    border-radius: 3px;
}

.timeline-item {
    position: relative;
    padding-bottom: var(--space-xl);
}

.timeline-item:last-child {
    padding-bottom: 0;
}

.timeline-marker {
    position: absolute;
    left: calc(-1 * var(--space-xl) + 4px);
    top: 0;
    width: 20px;
    height: 20px;
    background: var(--accent-primary);
    border-radius: 50%;
    border: 3px solid var(--bg-primary);
    box-shadow: var(--shadow-sm);
    z-index: 1;
}

.timeline-item.completed .timeline-marker {
    background: var(--success);
}

.timeline-item.active .timeline-marker {
    background: var(--warning);
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% { box-shadow: 0 0 0 0 rgba(255, 140, 0, 0.4); }
    50% { box-shadow: 0 0 0 8px rgba(255, 140, 0, 0); }
}

.timeline-content {
    background: var(--bg-secondary);
    padding: var(--space-lg);
    border-radius: var(--radius-md);
    border: 1px solid var(--border-color);
    margin-left: var(--space-sm);
}

.timeline-content h4 {
    margin: 0 0 var(--space-xs) 0;
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-primary);
}

.timeline-date {
    font-size: 0.8rem;
    color: var(--accent-primary);
    font-weight: 500;
    margin-bottom: var(--space-sm);
    display: block;
}

.timeline-content p {
    margin: 0;
    font-size: 0.9rem;
    color: var(--text-secondary);
    line-height: 1.5;
}

/* Horizontal Stepper variant */
.stepper {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin: var(--space-xl) 0;
    padding: var(--space-lg) 0;
    position: relative;
}

.stepper::before {
    content: '';
    position: absolute;
    top: 35px;
    left: 50px;
    right: 50px;
    height: 3px;
    background: var(--border-color);
}

.stepper-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    flex: 1;
    position: relative;
    z-index: 1;
}

.stepper-marker {
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background: var(--bg-secondary);
    border: 3px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: var(--space-md);
    transition: all 0.3s ease;
}

.stepper-item.completed .stepper-marker {
    background: var(--success);
    border-color: var(--success);
    color: white;
}

.stepper-item.active .stepper-marker {
    background: var(--accent-primary);
    border-color: var(--accent-primary);
    color: white;
    transform: scale(1.1);
}

.stepper-label {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-secondary);
    max-width: 120px;
}

.stepper-item.completed .stepper-label,
.stepper-item.active .stepper-label {
    color: var(--text-primary);
}

/* ===========================================
   Alternative Timeline with Dots (timeline-container)
   =========================================== */

.timeline-container {
    margin: var(--space-xl) 0;
    position: relative;
    padding-left: 40px;
}

.timeline-container::before {
    content: '';
    position: absolute;
    left: 15px;
    top: 0;
    bottom: 0;
    width: 2px;
    background: var(--border-color);
}

.timeline-container .timeline-item {
    position: relative;
    margin-bottom: var(--space-xl);
    padding-left: var(--space-md);
}

.timeline-container .timeline-item:last-child {
    margin-bottom: 0;
}

.timeline-dot {
    position: absolute;
    left: -35px;
    top: 0;
    width: 32px;
    height: 32px;
    background: var(--accent-primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-weight: 600;
    font-size: 0.875rem;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
    z-index: 1;
}

.timeline-container .timeline-content {
    background: var(--bg-secondary);
    padding: var(--space-lg);
    border-radius: var(--radius-md);
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow-sm);
}

.timeline-container .timeline-content h3,
.timeline-container .timeline-content h4 {
    margin: 0 0 var(--space-sm) 0;
    color: var(--accent-primary);
    font-size: 1.1rem;
}

.timeline-container .timeline-content p {
    margin: 0;
    color: var(--text-secondary);
    line-height: 1.6;
}

.timeline-container .timeline-content ul {
    margin: var(--space-sm) 0 0 0;
    padding-left: var(--space-lg);
}

.timeline-container .timeline-content li {
    margin-bottom: var(--space-xs);
    color: var(--text-secondary);
}

/* ===========================================
   Button-based Knowledge Checks (alternative format)
   =========================================== */

.knowledge-check h4 {
    margin: 0 0 var(--space-md) 0;
    color: var(--accent-secondary);
    font-size: 1rem;
    font-weight: 600;
}

.knowledge-check p:not(.feedback) {
    font-size: 1.05rem;
    line-height: 1.5;
    margin-bottom: var(--space-lg);
}

.knowledge-check .options {
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
}

.knowledge-check .options button {
    display: block;
    width: 100%;
    text-align: left;
    padding: var(--space-md) var(--space-lg);
    margin: 0;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    background: var(--bg-primary);
    color: var(--text-primary);
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.2s ease;
}

.knowledge-check .options button:hover:not(:disabled) {
    border-color: var(--accent-primary);
    background: var(--accent-light);
}

.knowledge-check .options button:disabled {
    cursor: default;
    opacity: 0.85;
}

.knowledge-check .options button.correct {
    background: #e6f7e6;
    border-color: var(--success);
    color: var(--success);
}

.knowledge-check .options button.incorrect {
    background: #fde7e9;
    border-color: var(--error);
    color: var(--error);
}

.knowledge-check .feedback {
    margin-top: var(--space-lg);
    padding: var(--space-md);
    border-radius: var(--radius-md);
    font-weight: 500;
    display: none;
}

.knowledge-check .feedback:not(:empty) {
    display: block;
}

.knowledge-check .feedback.correct {
    background: #e6f7e6;
    color: var(--success);
    border-left: 4px solid var(--success);
}

.knowledge-check .feedback.incorrect {
    background: #fde7e9;
    color: var(--error);
    border-left: 4px solid var(--error);
}

/* ===========================================
   Dark mode adjustments for LMS components
   =========================================== */

[data-theme="dark"] .timeline-dot {
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
}

[data-theme="dark"] .knowledge-check .options button.correct {
    background: rgba(16, 124, 16, 0.2);
}

[data-theme="dark"] .knowledge-check .options button.incorrect {
    background: rgba(209, 52, 56, 0.2);
}

[data-theme="dark"] .knowledge-check .feedback.correct {
    background: rgba(16, 124, 16, 0.2);
}

[data-theme="dark"] .knowledge-check .feedback.incorrect {
    background: rgba(209, 52, 56, 0.2);
}

[data-theme="dark"] .flip-card-back {
    background: var(--bg-tertiary);
}

[data-theme="dark"] .knowledge-check-option.correct {
    background: rgba(16, 124, 16, 0.2);
}

[data-theme="dark"] .knowledge-check-option.incorrect {
    background: rgba(209, 52, 56, 0.2);
}

[data-theme="dark"] .knowledge-check-feedback.correct {
    background: rgba(16, 124, 16, 0.2);
}

[data-theme="dark"] .knowledge-check-feedback.incorrect {
    background: rgba(209, 52, 56, 0.2);
}

[data-theme="dark"] .checklist-item.checked {
    background: rgba(16, 124, 16, 0.15);
}

[data-theme="dark"] .info-box.warning {
    background-color: rgba(255, 140, 0, 0.15);
}

[data-theme="dark"] .info-box.error {
    background-color: rgba(209, 52, 56, 0.15);
}

[data-theme="dark"] .info-box.success {
    background-color: rgba(16, 124, 16, 0.15);
}

/* ===========================================
   Responsive adjustments for LMS components
   =========================================== */

@media (max-width: 768px) {
    .flip-card-container {
        grid-template-columns: 1fr;
    }
    
    .flip-card {
        height: 180px;
    }
    
    .tabs-nav {
        flex-wrap: nowrap;
        -webkit-overflow-scrolling: touch;
    }
    
    .tab-btn {
        min-width: 100px;
        padding: var(--space-sm) var(--space-md);
        font-size: 0.85rem;
    }
    
    .stepper {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--space-lg);
    }
    
    .stepper::before {
        top: 0;
        bottom: 0;
        left: 25px;
        right: auto;
        width: 3px;
        height: auto;
    }
    
    .stepper-item {
        flex-direction: row;
        text-align: left;
        gap: var(--space-md);
    }
    
    .stepper-label {
        max-width: none;
    }
    
    .tooltip {
        width: 220px;
        left: 0;
        transform: translateX(0) translateY(5px);
    }
    
    .tooltip::after {
        left: 20px;
        transform: none;
    }
}