/* Course Landing Page - Modern Responsive Styles */

:root {
    --primary-color: #2563eb;
    --primary-dark: #1d4ed8;
    --secondary-color: #10b981;
    --text-dark: #1f2937;
    --text-light: #6b7280;
    --bg-light: #f9fafb;
    --bg-white: #ffffff;
    --border-color: #e5e7eb;
    --error-color: #ef4444;
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
    --transition: all 0.3s ease;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    color: var(--text-dark);
    line-height: 1.6;
    overflow-x: hidden;
}

/* Header & Navigation */
header {
    background: var(--bg-white);
    box-shadow: var(--shadow-sm);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.header-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

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

/* Hero Section */
.hero {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
    color: white;
    padding: 4rem 2rem;
    text-align: center;
}

.hero-container {
    max-width: 1200px;
    margin: 0 auto;
}

.hero h1 {
    font-size: 3rem;
    font-weight: 800;
    margin-bottom: 1rem;
    animation: fadeInUp 0.8s ease;
}

.hero-subtitle {
    font-size: 1.5rem;
    margin-bottom: 2rem;
    opacity: 0.95;
    animation: fadeInUp 1s ease;
}

.hero-cta {
    display: inline-block;
    background: white;
    color: var(--primary-color);
    padding: 1rem 2.5rem;
    border-radius: 8px;
    font-size: 1.1rem;
    font-weight: 600;
    text-decoration: none;
    transition: var(--transition);
    animation: fadeInUp 1.2s ease;
    cursor: pointer;
}

.hero-cta:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

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

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
}

/* Section */
section {
    padding: 4rem 0;
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 3rem;
    color: var(--text-dark);
}

/* Course Overview */
.course-overview {
    background: var(--bg-white);
    padding-top: 4rem;
}

.course-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 3rem;
    margin-bottom: 3rem;
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
}

.course-description {
    background: white;
    padding: 2.5rem;
    border-radius: 16px;
    box-shadow: var(--shadow-lg);
    margin-bottom: 2rem;
}

.course-description h3 {
    font-size: 1.75rem;
    margin-bottom: 1.5rem;
    color: var(--text-dark);
    font-weight: 700;
    position: relative;
    padding-bottom: 0.75rem;
}

.course-description h3::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 60px;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    border-radius: 2px;
}

.course-description p {
    color: var(--text-light);
    margin-bottom: 2rem;
    font-size: 1.05rem;
    line-height: 1.8;
}

.course-description h4 {
    font-size: 1.3rem;
    margin-bottom: 1.5rem;
    color: var(--text-dark);
    font-weight: 600;
}

.highlights {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1.25rem;
}

.highlight-item {
    display: flex;
    align-items: flex-start;
    gap: 0.75rem;
    padding: 1rem;
    background: var(--bg-light);
    border-radius: 10px;
    border-left: 3px solid var(--secondary-color);
    transition: var(--transition);
}

.highlight-item:hover {
    background: #f0fdf4;
    transform: translateX(5px);
    box-shadow: var(--shadow-sm);
}

.highlight-item::before {
    content: '✓';
    background: linear-gradient(135deg, var(--secondary-color), #059669);
    color: white;
    width: 28px;
    height: 28px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
    flex-shrink: 0;
    font-size: 0.9rem;
    box-shadow: var(--shadow-md);
}

.course-pricing {
    background: var(--bg-light);
    padding: 2rem;
    border-radius: 12px;
    box-shadow: var(--shadow-md);
    position: sticky;
    top: 100px;
}

.price-display {
    text-align: center;
    margin-bottom: 2rem;
}

.current-price {
    font-size: 3rem;
    font-weight: 800;
    color: var(--primary-color);
}

.original-price {
    font-size: 1.2rem;
    color: var(--text-light);
    text-decoration: line-through;
    margin-left: 1rem;
}

.price-info {
    text-align: center;
    color: var(--text-light);
    font-size: 0.9rem;
    margin-bottom: 2rem;
}

.payment-form {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.form-section {
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 1.5rem;
    background: white;
}

.payment-section {
    background: #fef3c7;
    border-color: #fcd34d;
}

.form-section-title {
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 1rem;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid var(--border-color);
}

.payment-section .form-section-title {
    color: #92400e;
    border-bottom-color: #fcd34d;
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.form-group label {
    font-weight: 600;
    color: var(--text-dark);
}

.form-group input {
    padding: 0.75rem;
    border: 2px solid var(--border-color);
    border-radius: 6px;
    font-size: 1rem;
    transition: var(--transition);
}

.form-group input:focus {
    outline: none;
    border-color: var(--primary-color);
}

.form-group input.error {
    border-color: var(--error-color);
}

.form-group .error-message {
    color: var(--error-color);
    font-size: 0.875rem;
    display: none;
}

.form-group.error .error-message {
    display: block;
}

.btn {
    padding: 1rem 2rem;
    border: none;
    border-radius: 6px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

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

.btn-primary:hover:not(:disabled) {
    background: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn-primary:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

.btn-loading {
    position: relative;
    color: transparent;
}

.btn-loading::after {
    content: '';
    position: absolute;
    width: 16px;
    height: 16px;
    border: 2px solid white;
    border-top-color: transparent;
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}

/* Benefits Section */
.benefits {
    background: var(--bg-light);
}

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

.benefit-card {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: var(--shadow-sm);
    text-align: center;
    transition: var(--transition);
}

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

.benefit-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.benefit-title {
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    color: var(--text-dark);
}

.benefit-text {
    color: var(--text-light);
}

/* Instructor Section */
.instructor {
    background: white;
}

.instructor-card {
    display: grid;
    grid-template-columns: 200px 1fr;
    gap: 2rem;
    background: var(--bg-light);
    padding: 2rem;
    border-radius: 12px;
}

.instructor-avatar img {
    width: 100%;
    border-radius: 50%;
}

.instructor-info h3 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
}

.instructor-title {
    color: var(--text-light);
    margin-bottom: 1rem;
}

.instructor-stats {
    display: flex;
    gap: 2rem;
    margin-top: 1rem;
}

.instructor-stat {
    display: flex;
    flex-direction: column;
}

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

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

/* Curriculum Section */
.curriculum {
    background: var(--bg-light);
}

.curriculum-list {
    max-width: 800px;
    margin: 0 auto;
}

.curriculum-item {
    background: white;
    margin-bottom: 1rem;
    border-radius: 8px;
    box-shadow: var(--shadow-sm);
    overflow: hidden;
}

.curriculum-header {
    padding: 1.5rem;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: var(--transition);
}

.curriculum-header:hover {
    background: var(--bg-light);
}

.curriculum-header h4 {
    font-size: 1.25rem;
}

.curriculum-header .week {
    color: var(--text-light);
    font-size: 0.875rem;
    margin-right: 1rem;
}

.toggle-icon {
    font-size: 1.5rem;
    transition: var(--transition);
}

.curriculum-item.active .toggle-icon {
    transform: rotate(180deg);
}

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

.curriculum-item.active .curriculum-content {
    max-height: 1000px;
}

.curriculum-lessons {
    padding: 0 1.5rem 1.5rem;
}

.curriculum-lessons ul {
    list-style: none;
    padding-left: 0;
}

.curriculum-lessons li {
    padding: 0.5rem 0;
    padding-left: 1.5rem;
    position: relative;
}

.curriculum-lessons li::before {
    content: '▸';
    position: absolute;
    left: 0;
    color: var(--primary-color);
}

/* Testimonials Section */
.testimonials {
    background: white;
}

.testimonials-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.testimonial-card {
    background: var(--bg-light);
    padding: 2rem;
    border-radius: 12px;
    box-shadow: var(--shadow-sm);
}

.testimonial-header {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1rem;
}

.testimonial-avatar {
    width: 50px;
    height: 50px;
    border-radius: 50%;
}

.testimonial-info h5 {
    font-size: 1rem;
    margin-bottom: 0.25rem;
}

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

.testimonial-rating {
    color: #fbbf24;
    margin-bottom: 1rem;
}

.testimonial-text {
    color: var(--text-dark);
    font-style: italic;
}

/* FAQ Section */
.faq {
    background: var(--bg-light);
}

.faq-list {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    background: white;
    margin-bottom: 1rem;
    border-radius: 8px;
    box-shadow: var(--shadow-sm);
    overflow: hidden;
}

.faq-question {
    padding: 1.5rem;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: var(--transition);
}

.faq-question:hover {
    background: var(--bg-light);
}

.faq-question h4 {
    font-size: 1.1rem;
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
}

.faq-item.active .faq-answer {
    max-height: 500px;
}

.faq-answer-content {
    padding: 0 1.5rem 1.5rem;
    color: var(--text-light);
}

/* Video Section */
.videos {
    background: white;
}

.videos-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: 2rem;
}

.video-card {
    position: relative;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow-md);
    cursor: pointer;
    transition: var(--transition);
}

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

.video-thumbnail {
    width: 100%;
    height: 250px;
    object-fit: cover;
}

.video-play-overlay {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background: rgba(0, 0, 0, 0.7);
    color: white;
    padding: 2rem;
    border-radius: 50%;
    font-size: 3rem;
}

.video-title {
    padding: 1rem;
    font-weight: 600;
}

/* Gallery Section */
.gallery {
    background: var(--bg-light);
}

.gallery-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1rem;
}

.gallery-item {
    border-radius: 8px;
    overflow: hidden;
    cursor: pointer;
    transition: var(--transition);
}

.gallery-item:hover {
    transform: scale(1.05);
}

.gallery-item img {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

/* Modal */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.8);
    z-index: 2000;
    justify-content: center;
    align-items: center;
}

.modal.active {
    display: flex;
}

.modal-content {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    max-width: 90%;
    max-height: 90%;
    position: relative;
}

.modal-close {
    position: absolute;
    top: 1rem;
    right: 1rem;
    font-size: 2rem;
    cursor: pointer;
    background: none;
    border: none;
    color: var(--text-light);
}

.modal-video {
    width: 100%;
    max-width: 800px;
    height: auto;
}

/* Alert Messages */
.alert {
    padding: 1rem;
    border-radius: 8px;
    margin-bottom: 1rem;
    display: none;
}

.alert.error {
    background: #fee2e2;
    color: #991b1b;
    border: 1px solid #fecaca;
}

.alert.success {
    background: #d1fae5;
    color: #065f46;
    border: 1px solid #a7f3d0;
}

.alert.info {
    background: #dbeafe;
    color: #1e40af;
    border: 1px solid #93c5fd;
}

.alert.active {
    display: block;
}

/* Payment Modal */
.payment-modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.85);
    z-index: 3000;
    justify-content: center;
    align-items: center;
    backdrop-filter: blur(5px);
}

.payment-modal.active {
    display: flex;
}

.payment-modal .modal-content {
    background: white;
    padding: 3rem;
    border-radius: 16px;
    max-width: 400px;
    width: 90%;
    text-align: center;
    box-shadow: var(--shadow-xl);
    animation: modalFadeIn 0.3s ease;
}

@keyframes modalFadeIn {
    from {
        opacity: 0;
        transform: scale(0.9);
    }
    to {
        opacity: 1;
        transform: scale(1);
    }
}

.modal-icon {
    font-size: 4rem;
    margin-bottom: 1rem;
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% {
        transform: scale(1);
    }
    50% {
        transform: scale(1.1);
    }
}

.modal-title {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 1rem;
}

.modal-message {
    font-size: 1rem;
    color: var(--text-light);
    margin-bottom: 2rem;
}

.modal-spinner {
    width: 40px;
    height: 40px;
    border: 4px solid var(--bg-light);
    border-top-color: var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto;
}

.modal-state {
    display: none;
}

.modal-state.active {
    display: block;
}

.success-icon, .error-icon {
    animation: none;
}

.modal-actions {
    display: flex;
    gap: 1rem;
    justify-content: center;
    margin-top: 1.5rem;
}

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

.btn-secondary:hover {
    background: var(--text-dark);
}

/* Footer */
footer {
    background: var(--text-dark);
    color: white;
    padding: 2rem;
    text-align: center;
}

/* Responsive Design */
@media (max-width: 768px) {
    .hero h1 {
        font-size: 2rem;
    }
    
    .hero-subtitle {
        font-size: 1.25rem;
    }
    
    .course-grid {
        grid-template-columns: 1fr;
    }
    
    .course-pricing {
        position: static;
    }
    
    .highlights {
        grid-template-columns: 1fr;
    }
    
    .instructor-card {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .instructor-stats {
        justify-content: center;
    }
    
    .videos-grid {
        grid-template-columns: 1fr;
    }
    
    .container {
        padding: 0 1rem;
    }
    
    section {
        padding: 2rem 0;
    }
}

/* Loading Spinner */
.spinner {
    border: 3px solid #f3f3f3;
    border-top: 3px solid var(--primary-color);
    border-radius: 50%;
    width: 40px;
    height: 40px;
    animation: spin 1s linear infinite;
    margin: 0 auto;
}

/* Success Message */
.success-message {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    text-align: center;
    box-shadow: var(--shadow-lg);
}

.success-icon {
    font-size: 4rem;
    color: var(--success-color);
    margin-bottom: 1rem;
}

.success-title {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    color: var(--text-dark);
}

.success-text {
    color: var(--text-light);
    margin-bottom: 2rem;
}

.success-info {
    background: var(--bg-light);
    padding: 1rem;
    border-radius: 8px;
    text-align: left;
    margin-bottom: 1rem;
}

.success-info-item {
    display: flex;
    justify-content: space-between;
    padding: 0.5rem 0;
    border-bottom: 1px solid var(--border-color);
}

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

.success-info-label {
    color: var(--text-light);
    font-weight: 600;
}

.success-info-value {
    color: var(--text-dark);
    font-weight: 600;
}