:root {
    /* colores principales - identidad visual */
    --primary-color: #0B2F4A;      
    --secondary-color: #1F6FA3;    
    --accent-color: #6EC1E4;       
    --dark-color: #2E2E2E;         
    --light-bg: #f8f9fa;
    --white: #FFFFFF;
    
    /* gradientes - uso en botones y headers */
    --gradient-primary: linear-gradient(135deg, #1F6FA3 0%, #6EC1E4 100%);
    --gradient-secondary: linear-gradient(135deg, #0B2F4A 0%, #1F6FA3 100%);
    --gradient-dark: linear-gradient(135deg, #0B2F4A 0%, #2E2E2E 100%);
    
    /* colores de estado - feedback visual */
    --success-color: #4caf50;
    --warning-color: #ffc107;
    --danger-color: #dc3545;
    --info-color: #1976d2;
    
    /* espaciado y efectos */
    --border-radius: 10px;
    --border-radius-sm: 5px;
    --border-radius-lg: 15px;
    --box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    --box-shadow-lg: 0 4px 20px rgba(0,0,0,0.15);
    --transition: all 0.3s ease;
    --transition-fast: all 0.15s ease;
    
    /* tipografia */
    --font-primary: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    --font-weight-normal: 400;
    --font-weight-medium: 500;
    --font-weight-bold: 700;
}


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

body {
    font-family: var(--font-primary);
    padding-top: 56px;
    line-height: 1.6;
    color: var(--dark-color);
    background: #f5f5f5;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* smooth scroll en toda la pagina */
html {
    scroll-behavior: smooth;
}

/* mejorar legibilidad de textos */
p, li {
    line-height: 1.7;
}

/* links sin decoracion por default */
a {
    text-decoration: none;
    color: inherit;
    transition: var(--transition-fast);
}

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


.navbar {
    background: var(--primary-color);
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    padding: 15px 0;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-logo {
    color: white;
    text-decoration: none;
    font-size: 1.5rem;
    font-weight: bold;
}

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

.nav-menu {
    list-style: none;
    display: flex;
    gap: 30px;
    align-items: center;
    margin: 0;
    padding: 0;
}

.nav-menu li {
    margin: 0;
}

.nav-menu a {
    color: white;
    text-decoration: none;
    transition: color 0.3s;
    padding: 5px 10px;
}

.nav-menu a:hover,
.nav-menu a.active {
    color: var(--accent-color);
}

.navbar-brand {
    font-size: 1.5rem;
}

.navbar-dark {
    background-color: var(--primary-color) !important;
}

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

.navbar .btn-primary:hover {
    background-color: #1a5d8a;
    border-color: #1a5d8a;
}

.nav-link:hover {
    color: var(--accent-color) !important;
}


.hero-section {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: white;
    padding: 100px 0;
    min-height: 600px;
    display: flex;
    align-items: center;
}

.hero-section .eslogan {
    color: var(--accent-color);
    font-size: 1.2rem;
    font-weight: 500;
    margin-bottom: 1rem;
}


.features-section {
    background: white;
}

.feature-card {
    border-radius: 10px;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    border: 1px solid #e9ecef;
}

.feature-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
}

.icon-circle {
    width: 80px;
    height: 80px;
    background: linear-gradient(135deg, var(--secondary-color) 0%, var(--accent-color) 100%);
    border-radius: 50%;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
    color: white;
    margin: 0 auto;
}


.course-card {
    border-radius: 10px;
    overflow: hidden;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    border: none;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    height: 100%;
}

.course-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.15);
}

.course-card img {
    height: 200px;
    object-fit: cover;
}

.course-price {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--secondary-color);
}

.course-instructor {
    display: flex;
    align-items: center;
    gap: 10px;
}

.instructor-avatar {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    object-fit: cover;
}


.event-card {
    border-left: 4px solid var(--secondary-color);
    transition: all 0.3s ease;
}

.event-card:hover {
    box-shadow: 0 5px 15px rgba(11, 47, 74, 0.2);
    border-left-color: var(--accent-color);
}

.event-date {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: white;
    padding: 15px;
    border-radius: 10px;
    text-align: center;
}

.event-date .day {
    font-size: 2rem;
    font-weight: bold;
    display: block;
}

.event-date .month {
    font-size: 0.9rem;
    text-transform: uppercase;
}


.cta-section {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: white;
}


.page-header {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: white;
    padding: 80px 0 60px;
    margin-bottom: 0;
}


.login-section,
.register-section {
    min-height: calc(100vh - 56px);
    display: flex;
    align-items: center;
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    padding: 50px 0;
}

.login-section .card,
.register-section .card {
    border: none;
    border-radius: 15px;
}


footer a {
    text-decoration: none;
    transition: color 0.3s ease;
}

footer a:hover {
    color: white !important;
}


.btn {
    border-radius: 8px;
    padding: 10px 25px;
    font-weight: 500;
    transition: all 0.3s ease;
}

.btn-primary {
    background: var(--secondary-color);
    border: none;
}

.btn-primary:hover {
    background: #1a5d8a;
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(31, 111, 163, 0.4);
}

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


.form-control:focus {
    border-color: var(--accent-color);
    box-shadow: 0 0 0 0.2rem rgba(110, 193, 228, 0.25);
}

.input-group-text {
    background-color: var(--light-bg);
    border: 1px solid #ced4da;
}


.badge {
    padding: 5px 10px;
    font-weight: 500;
}


.progress {
    height: 8px;
    border-radius: 10px;
}

.progress-bar {
    background: linear-gradient(90deg, var(--secondary-color) 0%, var(--accent-color) 100%);
}


.dashboard-card {
    border: none;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}


@media (max-width: 768px) {
    .hero-section {
        padding: 60px 0;
        min-height: auto;
    }

    .hero-section h1 {
        font-size: 2rem;
    }

    .page-header {
        padding: 60px 0 40px;
    }

    .page-header h1 {
 


.footer {
    background: var(--primary-color);
    color: white;
    padding: 30px 0;
    margin-top: 60px;
    text-align: center;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.footer p {
    margin: 0;
}


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

.mb-20 {
    margin-bottom: 20px;
}

.mt-20 {
    margin-top: 20px;
}

.p-20 {
    padding: 20px;
}


@media (max-width: 768px) {
    .nav-menu {
        flex-direction: column;
        gap: 15px;
    }
    
    .nav-container {
        flex-direction: column;
        gap: 15px;
    }
}

/* ========================================
   CURSO DETALLE - Course Detail Page
   ======================================== */
.course-hero {
    background: var(--gradient-primary);
    color: white;
    padding: 60px 20px;
    text-align: center;
}

.course-container {
    max-width: 1200px;
    margin: -50px auto 40px;
    padding: 0 20px;
}

.course-card {
    background: white;
    border-radius: 15px;
    overflow: hidden;
    box-shadow: var(--box-shadow);
}

.course-header {
    display: grid;
    grid-template-columns: 1fr 350px;
    gap: 40px;
    padding: 40px;
}

.course-main-content {
    flex: 1;
}

.course-title {
    font-size: 2.5rem;
    margin: 0 0 20px 0;
    color: #333;
}

.course-meta {
    display: flex;
    gap: 30px;
    flex-wrap: wrap;
    margin: 20px 0;
    padding: 20px 0;
    border-top: 1px solid #e0e0e0;
    border-bottom: 1px solid #e0e0e0;
}

.meta-item {
    display: flex;
    align-items: center;
    gap: 8px;
    color: #666;
}

.meta-item span:first-child {
    font-size: 1.2rem;
}

.course-sidebar {
    background: var(--light-bg);
    padding: 30px;
    border-radius: var(--border-radius);
    position: sticky;
    top: 80px;
}

.course-thumbnail {
    width: 100%;
    height: 200px;
    object-fit: cover;
    border-radius: var(--border-radius);
    margin-bottom: 20px;
}

.price-box {
    text-align: center;
    margin: 20px 0;
}

.price {
    font-size: 3rem;
    font-weight: bold;
    color: var(--secondary-color);
    margin: 10px 0;
}

.price-currency {
    font-size: 1.5rem;
    color: #999;
}

.btn-enroll {
    width: 100%;
    padding: 15px;
    background: var(--gradient-primary);
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    margin: 10px 0;
    text-decoration: none;
    display: block;
    text-align: center;
}

.btn-enroll:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(31, 111, 163, 0.4);
}

.btn-secondary {
    width: 100%;
    padding: 12px;
    background: white;
    color: var(--secondary-color);
    border: 2px solid var(--secondary-color);
    border-radius: 8px;
    font-size: 1rem;
    cursor: pointer;
    transition: var(--transition);
}

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

.course-includes {
    margin: 20px 0;
}

.includes-list {
    list-style: none;
    padding: 0;
}

.includes-list li {
    padding: 10px 0;
    display: flex;
    align-items: center;
    gap: 10px;
}

.includes-list li::before {
    content: "✓";
    color: var(--success-color);
    font-weight: bold;
    font-size: 1.2rem;
}

.course-tabs {
    display: flex;
    gap: 10px;
    padding: 40px 40px 0;
    border-bottom: 2px solid #e0e0e0;
}

.tab-btn {
    padding: 15px 30px;
    background: none;
    border: none;
    cursor: pointer;
    font-size: 1rem;
    color: #666;
    border-bottom: 3px solid transparent;
    transition: var(--transition);
}

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

.tab-content {
    padding: 40px;
    display: none;
}

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

.course-description {
    line-height: 1.8;
    color: #555;
    font-size: 1.1rem;
}

.curriculum-item {
    background: var(--light-bg);
    padding: 20px;
    margin: 15px 0;
    border-radius: 8px;
    border-left: 4px solid var(--secondary-color);
}

.curriculum-item h4 {
    margin: 0 0 10px 0;
    color: #333;
}

.reviews-section {
    margin-top: 20px;
}

.review-card {
    background: var(--light-bg);
    padding: 20px;
    margin: 15px 0;
    border-radius: 8px;
}

.review-header {
    display: flex;
    justify-content: space-between;
    margin-bottom: 10px;
}

.reviewer-name {
    font-weight: 600;
    color: #333;
}

.review-rating {
    color: var(--warning-color);
}

.instructor-card {
    display: flex;
    gap: 20px;
    align-items: center;
    background: var(--light-bg);
    padding: 20px;
    border-radius: 8px;
}

.instructor-avatar {
    width: 80px;
    height: 80px;
    border-radius: 50%;
    background: var(--gradient-primary);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 2rem;
    font-weight: bold;
}

.badge {
    display: inline-block;
    padding: 5px 15px;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 500;
    margin-right: 10px;
}

.badge-level {
    background: #e3f2fd;
    color: var(--info-color);
}

.badge-category {
    background: #f3e5f5;
    color: #7b1fa2;
}

.badge-success {
    background-color: #d4edda;
    color: #155724;
}

.badge-warning {
    background-color: #fff3cd;
    color: #856404;
}

.badge-info {
    background-color: #d1ecf1;
    color: #0c5460;
}

.badge-secondary {
    background-color: #e2e3e5;
    color: #383d41;
}

.enrolled-badge {
    background: var(--success-color);
    color: white;
    padding: 10px 20px;
    border-radius: 5px;
    text-align: center;
    margin: 10px 0;
}

/* ========================================
   MI PERFIL - Profile Page
   ======================================== */
.profile-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

.profile-header {
    background: var(--gradient-primary);
    color: white;
    padding: 40px;
    border-radius: var(--border-radius);
    margin-bottom: 30px;
    text-align: center;
}

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

.profile-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
    margin-bottom: 30px;
}

.stat-card {
    background: white;
    padding: 20px;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    text-align: center;
}

.stat-card h3 {
    color: var(--secondary-color);
    font-size: 2rem;
    margin: 10px 0;
}

.stat-card p {
    color: #666;
    margin: 0;
}

.tabs {
    display: flex;
    gap: 10px;
    margin-bottom: 20px;
    border-bottom: 2px solid #e0e0e0;
}

.tab {
    padding: 15px 30px;
    background: none;
    border: none;
    cursor: pointer;
    font-size: 1rem;
    color: #666;
    transition: var(--transition);
    border-bottom: 3px solid transparent;
}

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

.items-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 20px;
    margin-top: 20px;
}

.item-card {
    background: white;
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: var(--box-shadow);
    transition: var(--transition);
}

.item-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 4px 20px rgba(0,0,0,0.15);
}

.item-image {
    width: 100%;
    height: 180px;
    object-fit: cover;
    background: var(--gradient-primary);
}

.item-content {
    padding: 20px;
}

.item-title {
    font-size: 1.2rem;
    margin: 0 0 10px 0;
    color: #333;
}

.item-description {
    color: #666;
    margin: 0 0 15px 0;
    font-size: 0.9rem;
    line-height: 1.5;
}

.item-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: 15px;
    padding-top: 15px;
    border-top: 1px solid #e0e0e0;
}

.progress-bar {
    width: 100%;
    height: 8px;
    background-color: #e0e0e0;
    border-radius: 4px;
    overflow: hidden;
    margin-top: 10px;
}

.progress-fill {
    height: 100%;
    background: var(--gradient-primary);
    transition: width 0.3s;
}

.event-date {
    font-size: 0.9rem;
    color: var(--secondary-color);
    font-weight: 600;
}

.empty-state {
    text-align: center;
    padding: 60px 20px;
    color: #999;
}

.empty-state i {
    font-size: 4rem;
    margin-bottom: 20px;
    color: #ddd;
}

.loading {
    text-align: center;
    padding: 40px;
    color: var(--secondary-color);
    font-size: 1.2rem;
}

/* ========================================
   CURSO PLAYER - Course Player
   ======================================== */
.player-container {
    display: grid;
    grid-template-columns: 1fr 350px;
    height: calc(100vh - 60px);
    margin-top: 60px;
}

.video-section {
    background: #000;
    display: flex;
    flex-direction: column;
}

.video-player {
    flex: 1;
    background: #000;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
}

.video-placeholder {
    width: 100%;
    max-width: 900px;
    aspect-ratio: 16/9;
    background: var(--gradient-primary);
    border-radius: var(--border-radius);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 3rem;
}

.video-iframe {
    width: 100%;
    height: 100%;
}

.video-info {
    background: white;
    padding: 20px 30px;
}

.video-title {
    font-size: 1.5rem;
    margin: 0 0 10px 0;
    color: #333;
}

.video-meta {
    display: flex;
    gap: 20px;
    color: #666;
    font-size: 0.9rem;
}

.progress-section {
    margin-top: 15px;
}

.progress-label {
    display: flex;
    justify-content: space-between;
    margin-bottom: 5px;
    font-size: 0.9rem;
    color: #666;
}

.video-actions {
    display: flex;
    gap: 10px;
    margin-top: 15px;
}

.btn-action {
    padding: 10px 20px;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-size: 0.9rem;
    transition: var(--transition);
}

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

.btn-action.btn-secondary {
    background: #f0f0f0;
    color: #333;
}

.curriculum-sidebar {
    background: white;
    overflow-y: auto;
    border-left: 1px solid #e0e0e0;
}

.sidebar-header {
    padding: 20px;
    border-bottom: 1px solid #e0e0e0;
    background: var(--light-bg);
}

.sidebar-header h3 {
    margin: 0 0 10px 0;
    color: #333;
}

.module {
    border-bottom: 1px solid #e0e0e0;
}

.module-header {
    padding: 15px 20px;
    background: var(--light-bg);
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: var(--transition);
}

.module-header:hover {
    background: #e9ecef;
}

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

.module-icon {
    font-size: 0.8rem;
    transition: transform 0.3s;
}

.module.active .module-icon {
    transform: rotate(180deg);
}

.lessons-list {
    display: none;
}

.module.active .lessons-list {
    display: block;
}

.lesson-item {
    padding: 12px 20px 12px 40px;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: var(--transition);
    border-left: 3px solid transparent;
}

.lesson-item:hover {
    background: var(--light-bg);
}

.lesson-item.active {
    background: #e3f2fd;
    border-left-color: var(--secondary-color);
}

.lesson-item.completed {
    color: var(--success-color);
}

.lesson-title {
    flex: 1;
}

.lesson-duration {
    font-size: 0.85rem;
    color: #999;
}

.lesson-status {
    margin-left: 10px;
}

.completion-modal {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0,0,0,0.8);
    align-items: center;
    justify-content: center;
    z-index: 1000;
}

.completion-modal.hidden {
    display: none;
}

.completion-modal.show-flex {
    display: flex;
}

.modal-content {
    background: white;
    padding: 40px;
    border-radius: 15px;
    text-align: center;
    max-width: 500px;
}

.modal-content h2 {
    color: var(--secondary-color);
    margin-bottom: 20px;
}

.modal-icon {
    font-size: 5rem;
    margin-bottom: 20px;
}

.modal-text {
    font-size: 1.1rem;
    color: #666;
    margin: 20px 0;
}

.modal-btn {
    padding: 15px 40px;
    font-size: 1.1rem;
}

.video-placeholder-content {
    text-align: center;
}

.video-placeholder-icon {
    font-size: 5rem;
    margin-bottom: 20px;
}

.video-placeholder-text {
    font-size: 1.2rem;
}

.sidebar-stats {
    color: #666;
    margin: 0;
}


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

.loading-container {
    text-align: center;
    padding: 60px;
}

.loading-text {
    color: var(--secondary-color);
    font-size: 1.2rem;
}

.hidden {
    display: none;
}

.show-flex {
    display: flex !important;
}

.page-title {
    text-align: center;
    margin-bottom: 40px;
}

.card-grid-2col {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 15px;
}

.section-title-spacing {
    margin-top: 40px;
}

.text-muted {
    color: #666;
}

.text-small {
    font-size: 0.9rem;
    color: #999;
}

.discount-text {
    color: var(--success-color);
}

.icon-accent {
    color: var(--accent-color);
}

.checkout-section-mt {
    margin-top: 20px;
}

/* ========================================
   CHECKOUT - Payment Page
   ======================================== */
.checkout-container {
    max-width: 1000px;
    margin: 80px auto 40px;
    padding: 0 20px;
}

.checkout-grid {
    display: grid;
    grid-template-columns: 1fr 400px;
    gap: 30px;
}

.checkout-section {
    background: white;
    padding: 30px;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
}

.section-title {
    font-size: 1.5rem;
    margin: 0 0 20px 0;
    color: #333;
    padding-bottom: 15px;
    border-bottom: 2px solid #e0e0e0;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    color: #555;
    font-weight: 500;
}

.form-control {
    width: 100%;
    padding: 12px;
    border: 1px solid #ddd;
    border-radius: 5px;
    font-size: 1rem;
    transition: var(--transition);
}

.form-control:focus {
    outline: none;
    border-color: var(--secondary-color);
}

.payment-methods {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 15px;
    margin-bottom: 20px;
}

.payment-method {
    padding: 15px;
    border: 2px solid #e0e0e0;
    border-radius: 8px;
    cursor: pointer;
    text-align: center;
    transition: var(--transition);
}

.payment-method:hover {
    border-color: var(--secondary-color);
}

.payment-method.selected {
    border-color: var(--secondary-color);
    background: #e3f2fd;
}

.payment-method-icon {
    font-size: 2rem;
    margin-bottom: 5px;
}

.order-summary {
    background: var(--light-bg);
    padding: 20px;
    border-radius: 8px;
}

.course-summary {
    display: flex;
    gap: 15px;
    margin-bottom: 20px;
    padding-bottom: 20px;
    border-bottom: 1px solid #e0e0e0;
}

.price-breakdown {
    margin: 20px 0;
}

.price-row {
    display: flex;
    justify-content: space-between;
    margin: 10px 0;
    color: #666;
}

.price-row.total {
    font-size: 1.5rem;
    font-weight: bold;
    color: #333;
    padding-top: 15px;
    border-top: 2px solid #e0e0e0;
    margin-top: 15px;
}

.btn-purchase {
    width: 100%;
    padding: 18px;
    background: var(--gradient-primary);
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 1.2rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    margin-top: 20px;
}

.btn-purchase:hover {
    transform: translateY(-2px);
}

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

.security-badges {
    display: flex;
    justify-content: center;
    gap: 15px;
    margin-top: 20px;
    padding-top: 20px;
    border-top: 1px solid #e0e0e0;
    font-size: 0.85rem;
    color: #999;
}

.alert {
    padding: 15px;
    border-radius: 5px;
    margin-bottom: 20px;
}

.alert-info {
    background: #e3f2fd;
    color: var(--info-color);
    border-left: 4px solid var(--info-color);
}

.alert-success {
    background: #d4edda;
    color: #155724;
    border-left: 4px solid #155724;
}

/* ========================================
   RESPONSIVE - Media Queries
   ======================================== */
@media (max-width: 968px) {
    .course-header,
    .checkout-grid,
    .player-container {
        grid-template-columns: 1fr;
    }

    .course-sidebar,
    .curriculum-sidebar {
        position: static;
        max-height: 400px;
    }

    .course-title {
        font-size: 1.8rem;
    }

    .player-container {
        height: auto;
    }

    .video-section {
        height: auto;
    }

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

    .tabs,
    .tab {
        overflow-x: auto;
    }

    .tab {
        padding: 10px 20px;
        font-size: 0.9rem;
    }
}       font-size: 2rem;
    }
}


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

.fade-in-up {
    animation: fadeInUp 0.6s ease-out;
}


.spinner-border {
    width: 3rem;
    height: 3rem;
}


.star-rating {
    color: #ffc107;
}


.category-badge {
    background-color: rgba(110, 193, 228, 0.15);
    color: var(--primary-color);
    padding: 5px 15px;
    border-radius: 20px;
    font-size: 0.85rem;
    display: inline-block;
}


.video-container {
    position: relative;
    padding-bottom: 56.25%;
    height: 0;
    overflow: hidden;
    border-radius: 10px;
}

.video-container iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}