/* Base Styles & Variables */
:root {
    --primary-color: #4f46e5;
    --primary-dark: #4338ca;
    --secondary-color: #10b981;
    --text-color: #1f2937;
    --text-light: #6b7280;
    --bg-color: #ffffff;
    --bg-light: #f9fafb;
    --border-color: #e5e7eb;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-md: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --radius-sm: 0.375rem;
    --radius: 0.5rem;
    --transition: all 0.3s ease;
}

/* Dark Theme */
[data-theme="dark"] {
    --primary-color: #6366f1;
    --primary-dark: #4f46e5;
    --text-color: #f9fafb;
    --text-light: #d1d5db;
    --bg-color: #111827;
    --bg-light: #1f2937;
    --border-color: #374151;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Poppins', sans-serif;
    color: var(--text-color);
    background-color: var(--bg-color);
    line-height: 1.6;
    transition: var(--transition);
}

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

ul {
    list-style: none;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

.section {
    padding: 5rem 0;
}

.section-title {
    font-size: 2.25rem;
    font-weight: 700;
    margin-bottom: 3rem;
    text-align: center;
    position: relative;
}

.section-title::after {
    content: '';
    display: block;
    width: 80px;
    height: 4px;
    background: var(--primary-color);
    margin: 0.75rem auto 0;
    border-radius: 2px;
}

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

/* Buttons */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    border-radius: var(--radius);
    font-weight: 500;
    cursor: pointer;
    text-align: center;
    transition: var(--transition);
    border: none;
    font-family: inherit;
    font-size: 1rem;
}

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

.btn-primary:hover {
    background-color: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow);
}

.btn-outline {
    border: 2px solid var(--primary-color);
    color: var(--primary-color);
    background: transparent;
}

.btn-outline:hover {
    background-color: var(--primary-color);
    color: white;
    transform: translateY(-2px);
    box-shadow: var(--shadow);
}

.btn-lg {
    padding: 1rem 2rem;
    font-size: 1.1rem;
}

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

.btn-light:hover {
    background-color: #f3f4f6;
    transform: translateY(-2px);
    box-shadow: var(--shadow);
}

/* Navigation */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background-color: var(--bg-color);
    box-shadow: var(--shadow-sm);
    z-index: 1000;
    padding: 1rem 0;
    transition: var(--transition);
}

.navbar.scrolled {
    padding: 0.5rem 0;
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
}

[data-theme="dark"] .navbar.scrolled {
    background-color: rgba(17, 24, 39, 0.95);
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
}

.logo span {
    color: var(--text-color);
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: 2rem;
}

.nav-item .nav-link {
    font-weight: 500;
    padding: 0.5rem 0;
    position: relative;
}

.nav-item .nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--primary-color);
    transition: width 0.3s ease;
}

.nav-item .nav-link:hover::after,
.nav-item .nav-link.active::after {
    width: 100%;
}

.hamburger {
    display: none;
    cursor: pointer;
    z-index: 1001;
}

.bar {
    display: block;
    width: 25px;
    height: 3px;
    margin: 5px 0;
    background-color: var(--text-color);
    transition: var(--transition);
}

.theme-toggle {
    background: none;
    border: none;
    color: var(--text-color);
    font-size: 1.25rem;
    cursor: pointer;
    margin-left: 1rem;
    padding: 0.5rem;
    border-radius: 50%;
    transition: var(--transition);
}

.theme-toggle:hover {
    background-color: var(--bg-light);
}

/* Hero Section */
.hero {
    padding: 8rem 0 5rem;
    background: linear-gradient(135deg, #f0f9ff 0%, #e0f2fe 100%);
    min-height: 90vh;
    display: flex;
    align-items: center;
}

[data-theme="dark"] .hero {
    background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%);
}

.hero .container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    align-items: center;
}

.hero-content h1 {
    font-size: 3.5rem;
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 1.5rem;
    background: linear-gradient(to right, #4f46e5, #7c3aed);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero-content p {
    font-size: 1.25rem;
    color: var(--text-light);
    margin-bottom: 2rem;
    max-width: 90%;
}

.hero-image {
    position: relative;
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow-md);
    transition: var(--transition);
}

.hero-image:hover {
    transform: translateY(-5px);
    box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
}

.hero-image img {
    border-radius: var(--radius);
    transition: var(--transition);
}

/* Courses Grid */
.courses-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 2rem;
    margin-bottom: 3rem;
}

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

.course-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-md);
}

.course-image {
    height: 180px;
    overflow: hidden;
}

.course-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: var(--transition);
}

.course-card:hover .course-image img {
    transform: scale(1.05);
}

.course-content {
    padding: 1.5rem;
}

.course-category {
    display: inline-block;
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--primary-color);
    background-color: rgba(79, 70, 229, 0.1);
    padding: 0.25rem 0.75rem;
    border-radius: 9999px;
    margin-bottom: 0.75rem;
}

.course-title {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.75rem;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.course-description {
    color: var(--text-light);
    font-size: 0.9375rem;
    margin-bottom: 1.25rem;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.course-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.875rem;
    color: var(--text-light);
    padding-top: 1rem;
    border-top: 1px solid var(--border-color);
}

/* Features */
.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.feature-card {
    text-align: center;
    padding: 2rem 1.5rem;
    border-radius: var(--radius);
    background: var(--bg-color);
    box-shadow: var(--shadow);
    transition: var(--transition);
    border: 1px solid var(--border-color);
}

.feature-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-md);
}

.feature-icon {
    width: 70px;
    height: 70px;
    margin: 0 auto 1.5rem;
    background: rgba(79, 70, 229, 0.1);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.75rem;
    color: var(--primary-color);
    transition: var(--transition);
}

.feature-card:hover .feature-icon {
    background: var(--primary-color);
    color: white;
    transform: rotateY(180deg);
}

.feature-card h3 {
    font-size: 1.25rem;
    margin-bottom: 1rem;
}

/* CTA Section */
.cta {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
    color: white;
    text-align: center;
    padding: 5rem 0;
    position: relative;
    overflow: hidden;
}

.cta::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml;base64,PHN2ZyB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciIHdpZHRoPSIxMDAlIiBoZWlnaHQ9IjEwMCUiPjxkZWZzPjxwYXR0ZXJuIGlkPSJwYXR0ZXJuIiB3aWR0aD0iNDAiIGhlaWdodD0iNDAiIHBhdHRlcm5Vbml0cz0idXNlclNwYWNlT25Vc2UiIHBhdHRlcm5UcmFuc2Zvcm09InJvdGF0ZSg0NSkiPjxyZWN0IHdpZHRoPSIyMCIgaGVpZ2h0PSIyMCIgZmlsbD0icmdiYSgyNTUsMjU1LDI1NSwwLjA1KSIvPjwvcGF0dGVybj48L2RlZnM+PHJlY3QgZmlsbD0idXJsKCNwYXR0ZXJuKSIgd2lkdGg9IjEwMCUiIGhlaWdodD0iMTAwJSIvPjwvc3ZnPg==');
    opacity: 0.1;
}

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

.cta h2 {
    font-size: 2.5rem;
    margin-bottom: 1.5rem;
}

.cta p {
    font-size: 1.25rem;
    margin-bottom: 2rem;
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
    opacity: 0.9;
}

/* Footer */
.footer {
    background-color: var(--bg-light);
    padding: 5rem 0 0;
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 3rem;
    margin-bottom: 3rem;
}

.footer h3, .footer h4 {
    color: var(--text-color);
    margin-bottom: 1.5rem;
    font-weight: 600;
}

.footer-about p {
    margin-bottom: 1.5rem;
    color: var(--text-light);
}

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

.social-links a {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background-color: var(--bg-color);
    color: var(--text-color);
    transition: var(--transition);
}

.social-links a:hover {
    background-color: var(--primary-color);
    color: white;
    transform: translateY(-3px);
}

.footer-links ul li {
    margin-bottom: 0.75rem;
}

.footer-links a {
    color: var(--text-light);
    transition: var(--transition);
}

.footer-links a:hover {
    color: var(--primary-color);
    padding-left: 5px;
}

.footer-contact p {
    display: flex;
    align-items: center;
    margin-bottom: 1rem;
    color: var(--text-light);
}

.footer-contact i {
    margin-right: 0.75rem;
    color: var(--primary-color);
    width: 20px;
    text-align: center;
}

.footer-newsletter p {
    color: var(--text-light);
    margin-bottom: 1.5rem;
}

.footer-newsletter form {
    display: flex;
    gap: 0.5rem;
}

.footer-newsletter input {
    flex: 1;
    padding: 0.75rem 1rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    background-color: var(--bg-color);
    color: var(--text-color);
    font-family: inherit;
    transition: var(--transition);
}

.footer-newsletter input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.2);
}

.footer-newsletter button {
    white-space: nowrap;
}

.footer-bottom {
    padding: 1.5rem 0;
    border-top: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 1rem;
}

.footer-bottom p {
    color: var(--text-light);
    font-size: 0.875rem;
}

.footer-legal {
    display: flex;
    gap: 1.5rem;
}

.footer-legal a {
    color: var(--text-light);
    font-size: 0.875rem;
    transition: var(--transition);
}

.footer-legal a:hover {
    color: var(--primary-color);
}

/* Animations */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.fade-in {
    animation: fadeIn 0.6s ease-out forwards;
    opacity: 0;
}

/* Course Detail Page */
.course-detail {
    padding: 7rem 0 5rem;
}

.course-header {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 3rem;
    margin-bottom: 3rem;
}

.course-info h1 {
    font-size: 2.5rem;
    margin-bottom: 1.5rem;
}

.course-meta {
    display: flex;
    align-items: center;
    gap: 1.5rem;
    margin-bottom: 1.5rem;
    color: var(--text-light);
    font-size: 0.9375rem;
}

.course-meta span {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.course-meta i {
    color: var(--primary-color);
}

.course-instructor {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 2rem;
}

.instructor-avatar {
    width: 50px;
    height: 50px;
    border-radius: 50%;
    overflow: hidden;
}

.instructor-info h4 {
    margin-bottom: 0.25rem;
}

.instructor-title {
    font-size: 0.875rem;
    color: var(--text-light);
}

.course-cta {
    background: var(--bg-light);
    padding: 2rem;
    border-radius: var(--radius);
    position: sticky;
    top: 6rem;
    box-shadow: var(--shadow);
}

.course-price {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
    display: flex;
    align-items: center;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.course-price .discounted-price {
    color: var(--primary-color);
}

.course-price .original-price {
    text-decoration: line-through;
    color: var(--text-light);
    font-size: 1rem;
    font-weight: 500;
}

/* Discount badge */
.discount-badge {
    position: absolute;
    top: 1rem;
    right: 1rem;
    background-color: #ef4444;
    color: white;
    padding: 0.25rem 0.5rem;
    border-radius: 0.25rem;
    font-size: 0.75rem;
    font-weight: 600;
    z-index: 1;
}
    margin-bottom: 1.5rem;
}

.course-stats {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
    margin-bottom: 1.5rem;
    padding-bottom: 1.5rem;
    border-bottom: 1px solid var(--border-color);
}

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

.stat-value {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 0.25rem;
}

.stat-label {
    font-size: 0.875rem;
    color: var(--text-light);
}

.course-actions {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.course-syllabus {
    margin-top: 4rem;
}

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

.syllabus-title {
    font-size: 1.5rem;
    font-weight: 600;
}

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

.syllabus-tab {
    padding: 0.75rem 1.5rem;
    font-weight: 500;
    color: var(--text-light);
    cursor: pointer;
    border-bottom: 2px solid transparent;
    transition: var(--transition);
}

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

.module {
    margin-bottom: 1.5rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    overflow: hidden;
}

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

.module-header:hover {
    background-color: rgba(79, 70, 229, 0.05);
}

.module-title {
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.module-title i {
    color: var(--primary-color);
    transition: transform 0.3s ease;
}

.module-header.active .module-title i {
    transform: rotate(90deg);
}

.module-content {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease-out;
}

.module-header.active + .module-content {
    max-height: 2000px;
    transition: max-height 0.5s ease-in;
}

.lesson {
    padding: 1rem 1.5rem 1rem 3.5rem;
    border-top: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: space-between;
    transition: var(--transition);
}

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

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

.lesson-complete {
    width: 20px;
    height: 20px;
    border: 2px solid var(--border-color);
    border-radius: 4px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    flex-shrink: 0;
    transition: var(--transition);
}

.lesson-complete.completed {
    background-color: var(--primary-color);
    border-color: var(--primary-color);
    color: white;
}

.lesson-complete i {
    font-size: 0.75rem;
    display: none;
}

.lesson-complete.completed i {
    display: block;
}

.lesson-title {
    font-weight: 500;
}

.lesson-duration {
    font-size: 0.875rem;
    color: var(--text-light);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.lesson-preview {
    color: var(--primary-color);
    font-size: 0.875rem;
    font-weight: 500;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    transition: var(--transition);
}

.lesson-preview:hover {
    color: var(--primary-dark);
}

/* Course List Page */
.courses-header {
    text-align: center;
    margin-bottom: 3rem;
}

.courses-header h1 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

.courses-header p {
    color: var(--text-light);
    max-width: 700px;
    margin: 0 auto 2rem;
}

.courses-filters {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
    flex-wrap: wrap;
    gap: 1rem;
}

.search-bar {
    position: relative;
    flex: 1;
    max-width: 400px;
}

.search-bar input {
    width: 100%;
    padding: 0.75rem 1rem 0.75rem 3rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    font-family: inherit;
    font-size: 1rem;
    background-color: var(--bg-color);
    color: var(--text-color);
    transition: var(--transition);
}

.search-bar input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.2);
}

.search-bar i {
    position: absolute;
    left: 1rem;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-light);
}

.filter-group {
    display: flex;
    align-items: center;
    gap: 1rem;
    flex-wrap: wrap;
}

.filter-select {
    padding: 0.75rem 1rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    font-family: inherit;
    font-size: 1rem;
    background-color: var(--bg-color);
    color: var(--text-color);
    cursor: pointer;
    transition: var(--transition);
}

.filter-select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.2);
}

.course-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 2rem;
    margin-bottom: 3rem;
}

/* Pagination */
.pagination {
    display: flex;
    justify-content: center;
    gap: 0.5rem;
    margin-top: 3rem;
}

.page-link {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    border-radius: var(--radius-sm);
    background-color: var(--bg-color);
    color: var(--text-color);
    font-weight: 500;
    transition: var(--transition);
    border: 1px solid var(--border-color);
}

.page-link:hover, .page-link.active {
    background-color: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

.page-link.disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

/* Responsive Styles */
@media (max-width: 1024px) {
    .hero .container {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .hero-content p {
        margin-left: auto;
        margin-right: auto;
    }

    .hero-image {
        max-width: 600px;
        margin: 0 auto;
    }

    .course-header {
        grid-template-columns: 1fr;
    }

    .course-cta {
        position: static;
        margin-top: 2rem;
    }
}

@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        top: 0;
        right: -100%;
        width: 80%;
        max-width: 300px;
        height: 100vh;
        background-color: var(--bg-color);
        flex-direction: column;
        justify-content: flex-start;
        padding: 6rem 2rem 2rem;
        transition: var(--transition);
        box-shadow: -5px 0 15px rgba(0, 0, 0, 0.1);
        z-index: 1000;
    }

    .nav-menu.active {
        right: 0;
    }

    .hamburger {
        display: block;
    }

    .hamburger.active .bar:nth-child(1) {
        transform: translateY(8px) rotate(45deg);
    }

    .hamburger.active .bar:nth-child(2) {
        opacity: 0;
    }

    .hamburger.active .bar:nth-child(3) {
        transform: translateY(-8px) rotate(-45deg);
    }

    .hero {
        padding: 6rem 0 4rem;
    }

    .hero-content h1 {
        font-size: 2.5rem;
    }

    .section {
        padding: 4rem 0;
    }

    .section-title {
        font-size: 1.75rem;
    }

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

    .footer-grid {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

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

    .footer-legal {
        justify-content: center;
    }
}

@media (max-width: 576px) {
    .hero-content h1 {
        font-size: 2rem;
    }

    .hero-content p {
        font-size: 1.1rem;
    }

    .btn {
        padding: 0.6rem 1.2rem;
    }

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

    .course-stats {
        grid-template-columns: 1fr;
    }

    .courses-filters {
        flex-direction: column;
        align-items: stretch;
    }

    .search-bar {
        max-width: 100%;
    }
}