@import url('https://fonts.googleapis.com/css2?family=Mulish:wght@400;600;700&display=swap');

:root {
    /* DEFAULT TO LIGHT THEME */
    --bg-color: #F7F8FA;
    --bg-card: #FFFFFF;
    --text-main: #152A47;
    --text-muted: #4A5B73;
    --accent: #2E5AA6;
    --accent-hover: #1E3F7A;
    --border-color: #E2E8F0;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --hero-bg: #EAEFF5;

    /* Variables for smooth transitions */
    --transition: all 0.3s ease;
}

[data-theme="dark"] {
    --bg-color: #0D0D0D;
    --bg-card: #1E1E1E;
    --text-main: #F3F4F6;
    --text-muted: #9CA3AF;
    --accent: #2DD4D0;
    --accent-hover: #1CA3A0;
    --border-color: #374151;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.5);
    --hero-bg: linear-gradient(135deg, #0A2E2C 0%, #14504A 100%);
}

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

body {
    font-family: 'Mulish', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-main);
    transition: var(--transition);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

a {
    color: var(--accent);
    text-decoration: none;
    transition: var(--transition);
}

a:hover {
    color: var(--accent-hover);
}

/* Header */
.header {
    background-color: var(--bg-card);
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 50;
    transition: var(--transition);
}

.logo-link img {
    height: 40px;
}

.header-actions {
    display: flex;
    align-items: center;
    gap: 1.5rem;
}

.theme-toggle {
    background: none;
    border: none;
    color: var(--text-main);
    cursor: pointer;
    font-size: 1.2rem;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
}

.theme-toggle:hover {
    color: var(--accent);
}

.user-menu-btn {
    background: none;
    border: none;
    cursor: pointer;
    display: flex;
    align-items: center;
}

.user-avatar {
    border-radius: 50%;
    background-color: var(--accent);
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
}

/* Sidebar Menu */
.sidebar-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    z-index: 99;
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
}

.sidebar-overlay.active {
    opacity: 1;
    visibility: visible;
}

.sidebar-panel {
    position: fixed;
    top: 0;
    right: -350px;
    width: 320px;
    height: 100%;
    background-color: var(--bg-card);
    box-shadow: -4px 0 15px rgba(0, 0, 0, 0.1);
    z-index: 100;
    transition: right 0.3s ease;
    display: flex;
    flex-direction: column;
}

.sidebar-panel.active {
    right: 0;
}

.sidebar-header {
    padding: 2rem 1.5rem;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
}

.sidebar-user-info {
    display: flex;
    flex-direction: column;
}

.sidebar-user-info h3 {
    font-size: 1.1rem;
    font-weight: 700;
}

.sidebar-user-info p {
    font-size: 0.9rem;
    color: var(--accent);
}

.sidebar-close {
    background: none;
    border: none;
    color: var(--text-muted);
    font-size: 1.5rem;
    cursor: pointer;
    transition: var(--transition);
}

.sidebar-close:hover {
    color: var(--text-main);
}

.sidebar-nav {
    padding: 1.5rem 0;
    display: flex;
    flex-direction: column;
}

.sidebar-nav-item {
    padding: 1rem 1.5rem;
    display: flex;
    align-items: center;
    gap: 1rem;
    color: var(--text-main);
    font-weight: 600;
    transition: var(--transition);
}

button.sidebar-nav-item {
    width: 100%;
    background: none;
    border: none;
    font-family: inherit;
    font-size: 1rem;
    text-align: left;
    cursor: pointer;
}

.sidebar-nav-item:hover {
    background-color: var(--bg-color);
    color: var(--accent);
}

.sidebar-nav-item i {
    font-size: 1.2rem;
    width: 24px;
    text-align: center;
}

/* Authentication Forms */
.auth-container {
    display: flex;
    align-items: center;
    justify-content: center;
    flex: 1;
    min-height: 100vh;
    padding: 2rem;
}

.auth-card {
    background-color: var(--bg-card);
    border-radius: 12px;
    box-shadow: var(--shadow);
    padding: 2.5rem;
    width: 100%;
    max-width: 450px;
    border: 1px solid var(--border-color);
}

.auth-header {
    text-align: center;
    margin-bottom: 2rem;
}

.auth-header img {
    height: 48px;
    margin-bottom: 1.5rem;
}

.auth-header h1 {
    font-size: 1.8rem;
    margin-bottom: 0.5rem;
    color: var(--text-main);
}

.auth-header p {
    color: var(--text-muted);
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    font-size: 0.9rem;
    color: var(--text-main);
}

.form-control {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    background-color: var(--bg-color);
    color: var(--text-main);
    font-family: inherit;
    font-size: 1rem;
    transition: var(--transition);
}

.form-control:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 3px rgba(45, 212, 208, 0.2);
}

.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    background-color: var(--accent);
    color: #fff;
    border: none;
    border-radius: 8px;
    font-weight: 700;
    font-size: 1rem;
    cursor: pointer;
    text-align: center;
    transition: var(--transition);
    width: 100%;
}

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

.auth-footer {
    text-align: center;
    margin-top: 1.5rem;
    font-size: 0.9rem;
}

.alert {
    padding: 1rem;
    border-radius: 8px;
    margin-bottom: 1.5rem;
    font-size: 0.9rem;
    font-weight: 600;
}

.alert-danger {
    background-color: rgba(239, 68, 68, 0.1);
    color: #EF4444;
    border: 1px solid rgba(239, 68, 68, 0.2);
}

.alert-success {
    background-color: rgba(16, 185, 129, 0.1);
    color: #10B981;
    border: 1px solid rgba(16, 185, 129, 0.2);
}

/* --- HOME HERO & DASHBOARD --- */
.hero-section {
    background: var(--hero-bg);
    padding: 5rem 2rem 3rem;
    text-align: center;
    position: relative;
    border-bottom: 1px solid var(--border-color);
}

.hero-content h1 {
    font-size: 3rem;
    font-weight: 700;
    line-height: 1.3;
    margin-bottom: 2rem;
    color: var(--text-main);
}

.hero-content .highlight {
    color: var(--accent);
    font-size: 4.5rem;
}

.scroll-indicator {
    display: inline-block;
    color: var(--text-muted);
    font-size: 1rem;
    margin-top: 2rem;
    animation: bounce 2s infinite;
}

.scroll-indicator i {
    display: block;
    font-size: 1.5rem;
    margin-top: 0.5rem;
    color: var(--accent);
}

@keyframes bounce {

    0%,
    20%,
    50%,
    80%,
    100% {
        transform: translateY(0);
    }

    40% {
        transform: translateY(-10px);
    }

    60% {
        transform: translateY(-5px);
    }
}

.main-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 3rem 2rem;
    width: 100%;
}

.section-title {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
    color: var(--text-main);
}

/* Continue Section */
.continue-section {
    margin-bottom: 3rem;
}

.continue-card {
    display: flex;
    align-items: center;
    background-color: var(--bg-card);
    border-radius: 12px;
    overflow: hidden;
    padding: 1.5rem;
    gap: 1.5rem;
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.continue-card:hover {
    border-color: var(--accent);
    transform: translateY(-2px);
}

.continue-thumb {
    width: 60px;
    height: 60px;
    border-radius: 8px;
    background-color: rgba(45, 212, 208, 0.1);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    color: var(--accent);
    border: 1px solid var(--border-color);
}

.continue-info {
    flex: 1;
}

.continue-info h3 {
    font-size: 1.1rem;
    color: var(--text-main);
    margin-bottom: 0.25rem;
}

.continue-info p {
    font-size: 0.9rem;
    color: var(--text-muted);
    margin-bottom: 1rem;
}

/* Progress Bar */
.progress-bar-container {
    width: 100%;
    height: 8px;
    background-color: rgba(0, 0, 0, 0.1);
    border-radius: 4px;
    overflow: hidden;
}

[data-theme="dark"] .progress-bar-container {
    background-color: rgba(255, 255, 255, 0.1);
}

.progress-bar {
    height: 100%;
    background-color: var(--accent);
    border-radius: 4px;
}

.progress-bar-container.slim {
    height: 4px;
}

/* Courses Grid */
.courses-section {
    margin-bottom: 4rem;
}

.courses-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 2rem;
}

.course-card {
    background-color: var(--bg-card);
    border-radius: 12px;
    overflow: hidden;
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow);
    display: flex;
    flex-direction: column;
    transition: var(--transition);
}

.course-card:hover {
    transform: translateY(-4px);
    border-color: var(--border-color);
}

.course-cover {
    height: 160px;
    background-color: rgba(0, 0, 0, 0.05);
    position: relative;
    border-bottom: 1px solid var(--border-color);
}

[data-theme="dark"] .course-cover {
    background-color: rgba(255, 255, 255, 0.02);
}

.course-cover img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.cover-placeholder {
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 3rem;
    color: var(--text-muted);
    opacity: 0.3;
}

.course-details {
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
    flex: 1;
}

.course-details h3 {
    font-size: 1.1rem;
    margin-bottom: 1.5rem;
    flex: 1;
    color: var(--text-main);
}

.course-footer {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-top: 1rem;
}

.btn-access {
    font-size: 0.9rem;
    font-weight: 700;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--text-main);
}

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

.contents-count {
    font-size: 0.8rem;
    color: var(--text-muted);
}

/* Highlights Grid */
.highlights-section {
    margin-bottom: 4rem;
}

.highlights-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
}

.highlight-card {
    background-color: var(--bg-card);
    border-radius: 12px;
    padding: 1.5rem;
    border: 1px solid var(--border-color);
    display: flex;
    align-items: flex-start;
    gap: 1rem;
    box-shadow: var(--shadow);
}

.highlight-icon {
    width: 45px;
    height: 45px;
    border-radius: 50%;
    background-color: rgba(45, 212, 208, 0.1);
    color: var(--accent);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.3rem;
    flex-shrink: 0;
}

.highlight-text h3 {
    font-size: 1.2rem;
    margin-bottom: 0.5rem;
    color: var(--text-main);
}

.highlight-text p {
    font-size: 0.9rem;
    color: var(--text-muted);
    line-height: 1.4;
}

/* Footer */
.footer {
    background-color: var(--bg-card);
    border-top: 1px solid var(--border-color);
    padding: 2rem;
    margin-top: auto;
}

.footer-container {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 1.5rem;
}

.footer .logo-img {
    height: 30px;
}

.footer-text {
    color: var(--text-muted);
    font-size: 0.9rem;
    flex: 1;
    text-align: center;
}

.social-icons {
    display: flex;
    gap: 1rem;
}

.social-icons a {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    background-color: transparent;
    color: var(--text-muted);
    display: flex;
    align-items: center;
    justify-content: center;
    border: 1px solid var(--text-muted);
    transition: var(--transition);
}

.social-icons a:hover {
    background-color: var(--accent);
    color: #fff;
    border-color: var(--accent);
}

/* --- COURSE DETAILS --- */
.course-header-wrapper {
    background-color: var(--bg-card);
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 2rem;
}

.back-link {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--text-muted);
    font-weight: 600;
    margin-bottom: 2rem;
    transition: var(--transition);
}

.back-link:hover {
    color: var(--text-main);
}

.course-hero {
    display: flex;
    align-items: stretch;
    justify-content: space-between;
    gap: 2rem;
    flex-wrap: wrap;
}

.course-hero-content {
    flex: 1;
    min-width: 300px;
}

.course-badge {
    display: inline-block;
    background-color: rgba(45, 212, 208, 0.1);
    color: var(--accent);
    padding: 0.25rem 0.75rem;
    border-radius: 12px;
    font-size: 0.8rem;
    font-weight: 700;
    margin-bottom: 1rem;
}

.course-hero-content h1 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    color: var(--text-main);
}

.course-progress-text {
    font-size: 0.9rem;
    color: var(--text-muted);
    margin-bottom: 0.5rem;
}

.course-hero-aside {
    width: 350px;
}

.last-lesson-card {
    display: flex;
    align-items: center;
    background-color: var(--bg-color);
    border-radius: 12px;
    overflow: hidden;
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow);
    transition: var(--transition);
    height: 100%;
}

.last-lesson-card:hover {
    border-color: var(--accent);
}

.last-lesson-thumb {
    width: 120px;
    height: 100%;
    min-height: 120px;
    background-color: rgba(0, 0, 0, 0.1);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
    color: var(--accent);
}

[data-theme="dark"] .last-lesson-thumb {
    background-color: rgba(255, 255, 255, 0.05);
}

.last-lesson-info {
    padding: 1.5rem;
    flex: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.last-lesson-label {
    font-size: 0.8rem;
    color: var(--text-muted);
    margin-bottom: 0.25rem;
}

.last-lesson-info h4 {
    font-size: 1rem;
    color: var(--text-main);
}

/* Modules & Carousel */
.course-body {
    padding-top: 3rem;
}

.module-section {
    margin-bottom: 4rem;
    overflow: hidden;
}

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

.module-header h2 {
    font-size: 1.3rem;
    display: flex;
    align-items: center;
    gap: 1rem;
    color: var(--text-main);
}

.module-counter {
    font-size: 0.85rem;
    color: var(--text-muted);
    font-weight: 400;
    background: var(--bg-color);
    padding: 0.25rem 0.75rem;
    border-radius: 12px;
}

.carousel-nav {
    display: flex;
    gap: 0.5rem;
}

.carousel-btn {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    border: 1px solid var(--border-color);
    background-color: var(--bg-card);
    color: var(--text-main);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: var(--transition);
}

.carousel-btn:hover {
    background-color: var(--accent);
    color: #fff;
    border-color: var(--accent);
}

.carousel-container {
    width: 100%;
    overflow-x: auto;
    scroll-behavior: smooth;
    -ms-overflow-style: none;
    scrollbar-width: none;
}

.carousel-container::-webkit-scrollbar {
    display: none;
}

.carousel-track {
    display: flex;
    gap: 1.5rem;
    width: max-content;
    padding-bottom: 1rem;
}

.lesson-card {
    width: 250px;
    display: flex;
    flex-direction: column;
    transition: var(--transition);
    border-radius: 8px;
    overflow: hidden;
    border: 1px solid transparent;
    padding: 0.5rem;
}

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

.lesson-card:hover .lesson-thumb {
    border-color: var(--accent);
}

.lesson-thumb {
    height: 140px;
    background-color: rgba(0, 0, 0, 0.05);
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    border: 1px solid var(--border-color);
    color: var(--accent);
    font-size: 2rem;
    transition: var(--transition);
}

[data-theme="dark"] .lesson-thumb {
    background-color: rgba(255, 255, 255, 0.02);
}

.lesson-duration {
    position: absolute;
    bottom: 8px;
    right: 8px;
    background-color: rgba(0, 0, 0, 0.7);
    color: #fff;
    font-size: 0.75rem;
    padding: 2px 6px;
    border-radius: 4px;
    font-weight: 600;
}

.lesson-completed {
    position: absolute;
    top: -1px;
    left: -1px;
    background-color: #10B981;
    color: white;
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-bottom-right-radius: 12px;
    border-top-left-radius: 8px;
    font-size: 1rem;
}

.lesson-title {
    margin-top: 1rem;
    font-size: 1rem;
    color: var(--text-main);
    font-weight: 600;
    line-height: 1.4;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

/* --- PLAYER UI --- */
.player-layout {
    display: flex;
    flex-direction: column;
    height: 100vh;
    overflow: hidden;
    background-color: var(--bg-color);
}

.player-header {
    height: 60px;
    background-color: var(--bg-card);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 1.5rem;
    border-bottom: 1px solid var(--border-color);
    flex-shrink: 0;
}

.player-nav-center {
    display: flex;
    align-items: center;
    gap: 1rem;
    flex: 1;
    justify-content: center;
}

.btn-nav {
    color: var(--text-main);
    font-weight: 600;
    font-size: 0.9rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    transition: var(--transition);
}

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

.btn-nav.disabled {
    color: var(--text-muted);
    cursor: not-allowed;
    pointer-events: none;
    opacity: 0.5;
}

.nav-divider {
    width: 1px;
    height: 20px;
    background-color: var(--border-color);
}

.player-main-wrapper {
    display: flex;
    flex: 1;
    overflow: hidden;
    position: relative;
}

.player-content-area {
    flex: 1;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
}

.video-container {
    width: 100%;
    aspect-ratio: 16 / 9;
    background-color: #000;
    position: relative;
}

.video-placeholder {
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    font-size: 1.2rem;
}

.document-container {
    width: 100%;
    padding: 4rem 2rem;
    background-color: var(--bg-card);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 1.5rem;
    border-bottom: 1px solid var(--border-color);
}

.document-icon {
    font-size: 4rem;
    color: var(--accent);
}

.lesson-info-section {
    padding: 2rem;
    max-width: 1000px;
    margin: 0 auto;
    width: 100%;
    flex: 1;
}

.lesson-tabs {
    display: flex;
    border-bottom: 1px solid var(--border-color);
    margin-bottom: 2rem;
}

.tab-btn {
    background: none;
    border: none;
    padding: 1rem 1.5rem;
    font-weight: 700;
    font-size: 1rem;
    color: var(--text-main);
    border-bottom: 3px solid transparent;
    cursor: pointer;
}

.tab-btn.active {
    color: var(--accent);
    border-bottom-color: var(--accent);
}

.btn-completed {
    background-color: #10B981 !important;
    color: white !important;
}

/* Sidebar Player */
.player-sidebar {
    width: 380px;
    background-color: var(--bg-card);
    border-left: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    flex-shrink: 0;
    transition: var(--transition);
}

.sidebar-top {
    padding: 1.5rem;
    border-bottom: 1px solid var(--border-color);
}

.sidebar-top-title {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.mobile-only-btn {
    display: none;
    background: none;
    border: none;
    font-size: 1.5rem;
    color: var(--text-muted);
    cursor: pointer;
}

.accordion-list {
    flex: 1;
    overflow-y: auto;
}

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

.accordion-header {
    padding: 1rem 1.5rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    cursor: pointer;
    transition: 0.3s;
    background-color: var(--bg-card);
}

.accordion-header:hover {
    background-color: rgba(0, 0, 0, 0.02);
}

[data-theme="dark"] .accordion-header:hover {
    background-color: rgba(255, 255, 255, 0.02);
}

.accordion-body {
    display: none;
    background-color: var(--bg-color);
}

.accordion-item.active .accordion-body {
    display: block;
}

.accordion-item.active .accordion-arrow {
    transform: rotate(180deg);
}

.sidebar-lesson-item {
    display: flex;
    padding: 1rem 1.5rem;
    border-bottom: 1px solid var(--border-color);
    align-items: flex-start;
    gap: 1rem;
    cursor: pointer;
    transition: 0.2s;
}

.sidebar-lesson-item:hover {
    background-color: rgba(0, 0, 0, 0.03);
}

[data-theme="dark"] .sidebar-lesson-item:hover {
    background-color: rgba(255, 255, 255, 0.03);
}

.sidebar-lesson-item.current {
    border-left: 4px solid var(--accent);
    background-color: rgba(45, 212, 208, 0.05);
}

/* Custom Checkbox */
.custom-checkbox {
    position: relative;
    display: block;
    width: 22px;
    height: 22px;
    cursor: pointer;
    flex-shrink: 0;
}

.custom-checkbox input {
    position: absolute;
    opacity: 0;
    cursor: pointer;
    height: 0;
    width: 0;
}

.checkmark {
    position: absolute;
    top: 0;
    left: 0;
    height: 22px;
    width: 22px;
    background-color: transparent;
    border: 2px solid var(--border-color);
    border-radius: 4px;
    transition: 0.2s;
}

.custom-checkbox:hover input~.checkmark {
    border-color: var(--accent);
}

.custom-checkbox input:checked~.checkmark {
    background-color: #10B981;
    border-color: #10B981;
}

.checkmark:after {
    content: "";
    position: absolute;
    display: none;
    left: 7px;
    top: 3px;
    width: 5px;
    height: 10px;
    border: solid white;
    border-width: 0 2px 2px 0;
    transform: rotate(45deg);
}

.custom-checkbox input:checked~.checkmark:after {
    display: block;
}

.sidebar-lesson-details {
    flex: 1;
}

.open-sidebar-mobile {
    display: none;
    position: fixed;
    bottom: 1rem;
    left: 50%;
    transform: translateX(-50%);
    z-index: 90;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
}

@media (max-width: 900px) {
    .header {
        padding: 1rem;
    }

    .hero-content h1 {
        font-size: 2.2rem;
    }

    .hero-content .highlight {
        font-size: 3rem;
    }

    .highlights-grid {
        grid-template-columns: 1fr;
    }

    .footer-container {
        flex-direction: column;
        text-align: center;
    }

    .footer-text {
        text-align: center;
    }

    .hero-section {
        padding: 3rem 1rem 2rem;
    }

    .course-hero-aside {
        width: 100%;
    }

    .carousel-nav {
        display: none;
    }

    .lesson-card {
        width: 220px;
    }

    .player-nav-center {
        display: none;
    }

    .player-sidebar {
        position: fixed;
        top: 0;
        right: -100%;
        width: 100%;
        max-width: 380px;
        height: 100vh;
        z-index: 100;
        box-shadow: -4px 0 15px rgba(0, 0, 0, 0.1);
    }

    .player-sidebar.mobile-open {
        right: 0;
    }

    .mobile-only-btn {
        display: block;
    }

    .open-sidebar-mobile {
        display: block;
    }
}

/* Module blocks inside course edit (Admin) */
.module-block {
    border-bottom: 1px solid var(--border-color);
}

.module-block:last-of-type {
    border-bottom: none;
}

.module-block-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 1.5rem;
    background-color: rgba(0, 0, 0, 0.02);
}

[data-theme="dark"] .module-block-header {
    background-color: rgba(255, 255, 255, 0.03);
}
/* ---------- Submódulos e aulas de texto ---------- */
.module-group-title {
    font-size: 1.5rem;
    color: var(--text-main);
    display: flex;
    align-items: center;
    gap: 1rem;
    flex-wrap: wrap;
    margin-bottom: 1.5rem;
    padding-bottom: 0.75rem;
    border-bottom: 1px solid var(--border-color);
}

.submodule-section {
    margin-left: 1.25rem;
    margin-bottom: 2.5rem;
}

.submodule-section .module-header h2 {
    font-size: 1.1rem;
}

.sidebar-module-group {
    padding: 0.9rem 1.5rem 0.5rem;
    font-weight: 700;
    color: var(--text-main);
    background-color: var(--bg-color);
    border-bottom: 1px solid var(--border-color);
}

.sidebar-module-group span {
    display: block;
    font-size: 0.8rem;
    font-weight: 400;
    color: var(--text-muted);
}

.accordion-subitem .accordion-header {
    padding-left: 2.25rem;
}

.text-lesson-container {
    width: 100%;
    padding: 2.5rem 2rem;
    background-color: var(--bg-card);
    color: var(--text-main);
    line-height: 1.7;
    border-bottom: 1px solid var(--border-color);
}

.text-lesson-container p,
.text-lesson-container ul,
.text-lesson-container ol {
    margin-bottom: 1rem;
}

.text-lesson-container h2,
.text-lesson-container h3 {
    margin: 1.5rem 0 0.75rem;
}

.text-lesson-container ul,
.text-lesson-container ol {
    padding-left: 1.5rem;
}

@media (max-width: 768px) {
    .submodule-section {
        margin-left: 0;
    }

    .text-lesson-container {
        padding: 1.5rem 1rem;
    }
}

/* Botão com aparência de link (ex.: "Sair" na troca de senha) */
.btn-link {
    background: none;
    border: none;
    padding: 0;
    color: var(--accent);
    font: inherit;
    cursor: pointer;
    text-decoration: underline;
}