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

html {
    font-size: 16px;
    line-height: 1.6;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    color: #333;
    background-color: #fff;
}

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

a {
    color: #2563eb;
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1rem;
}

/* Header */
.header {
    background: #fff;
    border-bottom: 1px solid #e5e7eb;
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 4rem;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.logo-text {
    font-weight: 600;
    font-size: 1.25rem;
    color: #1f2937;
}

.nav-list {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-link {
    color: #6b7280;
    font-weight: 500;
    padding: 0.5rem 0;
    border-bottom: 2px solid transparent;
    transition: all 0.2s;
}

.nav-link:hover,
.nav-link.active {
    color: #2563eb;
    border-bottom-color: #2563eb;
    text-decoration: none;
}

.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    gap: 0.25rem;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
}

.mobile-menu-toggle span {
    width: 1.5rem;
    height: 2px;
    background: #374151;
    transition: 0.3s;
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 4rem 0;
}

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

.hero-title {
    font-size: 3rem;
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: 1rem;
}

.hero-subtitle {
    font-size: 1.25rem;
    opacity: 0.9;
    margin-bottom: 2rem;
}

.hero-actions {
    display: flex;
    gap: 1rem;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    font-weight: 600;
    border-radius: 0.5rem;
    border: none;
    cursor: pointer;
    text-decoration: none;
    transition: all 0.2s;
    font-size: 1rem;
}

.btn-primary {
    background: #2563eb;
    color: white;
}

.btn-primary:hover {
    background: #1d4ed8;
    text-decoration: none;
}

.btn-secondary {
    background: transparent;
    color: white;
    border: 2px solid white;
}

.btn-secondary:hover {
    background: white;
    color: #2563eb;
    text-decoration: none;
}

.btn-outline {
    background: transparent;
    color: #2563eb;
    border: 2px solid #2563eb;
}

.btn-outline:hover {
    background: #2563eb;
    color: white;
    text-decoration: none;
}

/* Sections */
.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 3rem;
    color: #1f2937;
}

.page-header {
    background: #f9fafb;
    padding: 3rem 0;
    text-align: center;
}

.page-header h1 {
    font-size: 2.5rem;
    font-weight: 700;
    color: #1f2937;
    margin-bottom: 1rem;
}

.page-header p {
    font-size: 1.25rem;
    color: #6b7280;
    max-width: 600px;
    margin: 0 auto;
}

/* Features */
.features {
    padding: 4rem 0;
    background: #f9fafb;
}

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

.feature-card {
    background: white;
    padding: 2rem;
    border-radius: 0.75rem;
    text-align: center;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

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

.feature-card h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: #1f2937;
}

/* Course Cards */
.courses-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
}

.course-card {
    background: white;
    border-radius: 0.75rem;
    overflow: hidden;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    transition: transform 0.2s, box-shadow 0.2s;
}

.course-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 15px rgba(0, 0, 0, 0.15);
}

.course-image {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.course-content {
    padding: 1.5rem;
}

.course-category {
    display: inline-block;
    background: #dbeafe;
    color: #1e40af;
    padding: 0.25rem 0.75rem;
    border-radius: 9999px;
    font-size: 0.875rem;
    font-weight: 500;
    margin-bottom: 0.75rem;
}

.course-title {
    font-size: 1.25rem;
    font-weight: 600;
    color: #1f2937;
    margin-bottom: 0.5rem;
}

.course-title a {
    color: inherit;
    text-decoration: none;
}

.course-title a:hover {
    color: #2563eb;
}

.course-description {
    color: #6b7280;
    margin-bottom: 1rem;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.course-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
    font-size: 0.875rem;
    color: #6b7280;
}

.course-price {
    font-size: 1.5rem;
    font-weight: 700;
    color: #059669;
}

/* Featured Courses */
.featured-courses {
    padding: 4rem 0;
}

.section-footer {
    text-align: center;
    margin-top: 3rem;
}

/* Course Catalog */
.courses-catalog {
    padding: 2rem 0 4rem;
}

.catalog-filters {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: 1rem;
    margin-bottom: 2rem;
    padding: 1.5rem;
    background: #f9fafb;
    border-radius: 0.5rem;
}

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

.filter-label {
    font-weight: 500;
    color: #374151;
}

.search-input,
.filter-select {
    padding: 0.75rem;
    border: 1px solid #d1d5db;
    border-radius: 0.375rem;
    font-size: 1rem;
}

.search-input:focus,
.filter-select:focus {
    outline: none;
    border-color: #2563eb;
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

/* Course Detail */
.course-detail {
    padding: 2rem 0;
}

.course-hero {
    background: #f9fafb;
    padding: 3rem 0;
}

.course-hero-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 3rem;
    align-items: start;
}

.course-hero-main h1 {
    font-size: 2.5rem;
    font-weight: 700;
    color: #1f2937;
    margin-bottom: 1rem;
}

.course-hero-main p {
    font-size: 1.25rem;
    color: #6b7280;
    margin-bottom: 1.5rem;
}

.course-meta-list {
    display: flex;
    flex-wrap: wrap;
    gap: 2rem;
    margin-bottom: 2rem;
}

.course-meta-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: #6b7280;
}

.course-sidebar {
    background: white;
    padding: 2rem;
    border-radius: 0.75rem;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 5rem;
}

.course-price-large {
    font-size: 2rem;
    font-weight: 700;
    color: #059669;
    margin-bottom: 1.5rem;
}

.course-body {
    padding: 3rem 0;
}

.course-body-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 3rem;
}

.course-section {
    margin-bottom: 3rem;
}

.course-section h2 {
    font-size: 1.75rem;
    font-weight: 600;
    color: #1f2937;
    margin-bottom: 1rem;
}

.course-section ul {
    list-style: none;
    padding: 0;
}

.course-section li {
    padding: 0.5rem 0;
    padding-left: 1.5rem;
    position: relative;
}

.course-section li:before {
    content: '✓';
    position: absolute;
    left: 0;
    color: #059669;
    font-weight: bold;
}

.curriculum-list {
    background: #f9fafb;
    border-radius: 0.5rem;
    overflow: hidden;
}

.curriculum-item {
    padding: 1rem 1.5rem;
    border-bottom: 1px solid #e5e7eb;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

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

.curriculum-title {
    font-weight: 500;
    color: #1f2937;
}

.curriculum-duration {
    color: #6b7280;
    font-size: 0.875rem;
}

.instructor-card {
    background: #f9fafb;
    padding: 1.5rem;
    border-radius: 0.5rem;
    margin-bottom: 1.5rem;
}

.instructor-name {
    font-size: 1.125rem;
    font-weight: 600;
    color: #1f2937;
    margin-bottom: 0.5rem;
}

/* FAQ */
.faq-content {
    padding: 2rem 0 4rem;
}

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

.faq-category {
    margin-bottom: 3rem;
}

.faq-category h2 {
    font-size: 1.75rem;
    font-weight: 600;
    color: #1f2937;
    margin-bottom: 1.5rem;
}

.faq-item {
    border: 1px solid #e5e7eb;
    border-radius: 0.5rem;
    margin-bottom: 1rem;
    overflow: hidden;
}

.faq-question {
    width: 100%;
    padding: 1.5rem;
    background: #f9fafb;
    border: none;
    text-align: left;
    font-size: 1.125rem;
    font-weight: 500;
    color: #1f2937;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: background-color 0.2s;
}

.faq-question:hover {
    background: #f3f4f6;
}

.faq-question[aria-expanded="true"] {
    background: #e5e7eb;
}

.faq-toggle {
    font-size: 1.5rem;
    font-weight: bold;
    transition: transform 0.2s;
}

.faq-question[aria-expanded="true"] .faq-toggle {
    transform: rotate(45deg);
}

.faq-answer {
    padding: 0 1.5rem;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease, padding 0.3s ease;
}

.faq-question[aria-expanded="true"] + .faq-answer {
    padding: 1.5rem;
    max-height: 500px;
}

.faq-footer {
    text-align: center;
    margin-top: 4rem;
    padding: 3rem;
    background: #f9fafb;
    border-radius: 0.75rem;
}

.faq-footer h2 {
    font-size: 1.75rem;
    font-weight: 600;
    color: #1f2937;
    margin-bottom: 1rem;
}

/* Checkout */
.checkout {
    padding: 2rem 0 4rem;
}

.checkout-header {
    text-align: center;
    margin-bottom: 3rem;
}

.checkout-header h1 {
    font-size: 2.25rem;
    font-weight: 700;
    color: #1f2937;
    margin-bottom: 2rem;
}

.checkout-steps {
    display: flex;
    justify-content: center;
    gap: 2rem;
}

.step {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    border-radius: 9999px;
    background: #f3f4f6;
    color: #6b7280;
}

.step.active {
    background: #dbeafe;
    color: #1e40af;
}

.step.completed {
    background: #dcfce7;
    color: #166534;
}

.step-number {
    width: 2rem;
    height: 2rem;
    border-radius: 50%;
    background: currentColor;
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
    font-size: 0.875rem;
}

.checkout-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 3rem;
}

.checkout-form {
    background: white;
    padding: 2rem;
    border-radius: 0.75rem;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

.checkout-form h2 {
    font-size: 1.75rem;
    font-weight: 600;
    color: #1f2937;
    margin-bottom: 2rem;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
}

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

.form-label {
    display: block;
    font-weight: 500;
    color: #374151;
    margin-bottom: 0.5rem;
}

.form-input,
.form-select,
.form-textarea {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid #d1d5db;
    border-radius: 0.375rem;
    font-size: 1rem;
    transition: border-color 0.2s, box-shadow 0.2s;
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
    outline: none;
    border-color: #2563eb;
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.form-input.error,
.form-select.error,
.form-textarea.error {
    border-color: #dc2626;
}

.form-error {
    color: #dc2626;
    font-size: 0.875rem;
    margin-top: 0.25rem;
    min-height: 1.25rem;
}

.form-actions {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: 2rem;
}

.payment-security {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem;
    background: #f0fdf4;
    border-radius: 0.5rem;
    margin-bottom: 2rem;
}

.security-badges {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: #166534;
    font-weight: 500;
}

.payment-methods {
    display: flex;
    gap: 0.5rem;
}

.checkbox-label {
    display: flex;
    align-items: flex-start;
    gap: 0.75rem;
    cursor: pointer;
    line-height: 1.5;
}

.checkbox-label input[type="checkbox"] {
    opacity: 0;
    position: absolute;
}

.checkmark {
    width: 1.25rem;
    height: 1.25rem;
    border: 2px solid #d1d5db;
    border-radius: 0.25rem;
    position: relative;
    flex-shrink: 0;
    margin-top: 0.125rem;
}

.checkbox-label input[type="checkbox"]:checked + .checkmark {
    background: #2563eb;
    border-color: #2563eb;
}

.checkbox-label input[type="checkbox"]:checked + .checkmark:after {
    content: '✓';
    position: absolute;
    color: white;
    font-size: 0.875rem;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
}

/* Order Summary */
.order-summary {
    background: white;
    padding: 2rem;
    border-radius: 0.75rem;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 5rem;
}

.order-summary h3 {
    font-size: 1.25rem;
    font-weight: 600;
    color: #1f2937;
    margin-bottom: 1.5rem;
}

.order-item {
    display: flex;
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.order-item-image {
    width: 80px;
    height: 60px;
    object-fit: cover;
    border-radius: 0.375rem;
}

.order-item-details h4 {
    font-weight: 500;
    color: #1f2937;
    margin-bottom: 0.25rem;
}

.order-item-price {
    font-weight: 600;
    color: #059669;
}

.order-total {
    border-top: 1px solid #e5e7eb;
    padding-top: 1rem;
    margin-top: 1rem;
}

.order-total-row {
    display: flex;
    justify-content: space-between;
    margin-bottom: 0.5rem;
}

.order-total-final {
    font-size: 1.25rem;
    font-weight: 700;
    color: #1f2937;
}

/* Order Success */
.order-success {
    padding: 4rem 0;
    text-align: center;
}

.success-content {
    max-width: 600px;
    margin: 0 auto;
}

.success-icon {
    margin-bottom: 2rem;
}

.success-content h1 {
    font-size: 2.5rem;
    font-weight: 700;
    color: #059669;
    margin-bottom: 1rem;
}

.success-message {
    font-size: 1.25rem;
    color: #6b7280;
    margin-bottom: 3rem;
}

.order-details {
    background: #f9fafb;
    padding: 2rem;
    border-radius: 0.75rem;
    margin-bottom: 3rem;
    text-align: left;
}

.success-actions {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 3rem;
}

.success-note {
    background: #fef3c7;
    border: 1px solid #f59e0b;
    padding: 1.5rem;
    border-radius: 0.5rem;
    color: #92400e;
}

/* Contact */
.contact-content {
    padding: 2rem 0 4rem;
}

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

.contact-form-section h2,
.contact-info-section h2 {
    font-size: 1.75rem;
    font-weight: 600;
    color: #1f2937;
    margin-bottom: 1.5rem;
}

.contact-form {
    background: white;
    padding: 2rem;
    border-radius: 0.75rem;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

.contact-method {
    margin-bottom: 2rem;
}

.contact-method h3 {
    font-size: 1.125rem;
    font-weight: 600;
    color: #1f2937;
    margin-bottom: 0.5rem;
}

.contact-note {
    font-size: 0.875rem;
    color: #6b7280;
    margin-top: 0.25rem;
}

.support-hours {
    list-style: none;
    padding: 0;
}

.support-hours li {
    padding: 0.25rem 0;
    color: #6b7280;
}

.form-success {
    background: #dcfce7;
    border: 1px solid #16a34a;
    color: #166534;
    padding: 1rem;
    border-radius: 0.5rem;
    margin-top: 1rem;
}

.faq-preview {
    text-align: center;
    padding: 3rem;
    background: #f9fafb;
    border-radius: 0.75rem;
}

.faq-preview h2 {
    font-size: 1.75rem;
    font-weight: 600;
    color: #1f2937;
    margin-bottom: 1rem;
}

/* About */
.about-content {
    padding: 2rem 0 4rem;
}

.about-section {
    max-width: 800px;
    margin: 0 auto 3rem;
}

.about-section h2 {
    font-size: 1.75rem;
    font-weight: 600;
    color: #1f2937;
    margin-bottom: 1rem;
}

.about-list {
    padding-left: 1rem;
}

.about-list li {
    margin-bottom: 0.5rem;
}

.cta-section {
    text-align: center;
    padding: 3rem;
    background: #f9fafb;
    border-radius: 0.75rem;
}

.cta-section h2 {
    font-size: 1.75rem;
    font-weight: 600;
    color: #1f2937;
    margin-bottom: 1rem;
}

/* Legal Pages */
.legal-content {
    padding: 2rem 0 4rem;
}

.legal-content .container {
    max-width: 800px;
}

.legal-content h1 {
    font-size: 2.5rem;
    font-weight: 700;
    color: #1f2937;
    margin-bottom: 0.5rem;
}

.last-updated {
    color: #6b7280;
    margin-bottom: 2rem;
}

.legal-section {
    margin-bottom: 2rem;
}

.legal-section h2 {
    font-size: 1.5rem;
    font-weight: 600;
    color: #1f2937;
    margin-bottom: 1rem;
}

.legal-section h3 {
    font-size: 1.25rem;
    font-weight: 600;
    color: #1f2937;
    margin: 1.5rem 0 0.5rem;
}

.legal-section ul {
    margin: 1rem 0;
    padding-left: 1.5rem;
}

.legal-section li {
    margin-bottom: 0.5rem;
}

/* Footer */
.footer {
    background: #1f2937;
    color: white;
    padding: 3rem 0 1rem;
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1.5fr;
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-section h4 {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

.footer-description {
    color: #d1d5db;
    line-height: 1.6;
}

.footer-links {
    list-style: none;
    padding: 0;
}

.footer-links li {
    margin-bottom: 0.5rem;
}

.footer-links a {
    color: #d1d5db;
    text-decoration: none;
    transition: color 0.2s;
}

.footer-links a:hover {
    color: white;
}

.contact-info {
    color: #d1d5db;
    line-height: 1.6;
}

.contact-info a {
    color: #d1d5db;
    text-decoration: none;
}

.contact-info a:hover {
    color: white;
}

.footer-bottom {
    border-top: 1px solid #374151;
    padding-top: 1rem;
    text-align: center;
    color: #9ca3af;
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav {
        display: none;
    }
    
    .mobile-menu-toggle {
        display: flex;
    }
    
    .hero-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .catalog-filters {
        grid-template-columns: 1fr;
    }
    
    .course-hero-content {
        grid-template-columns: 1fr;
    }
    
    .course-body-content {
        grid-template-columns: 1fr;
    }
    
    .checkout-content {
        grid-template-columns: 1fr;
    }
    
    .checkout-steps {
        flex-direction: column;
        align-items: center;
    }
    
    .form-row {
        grid-template-columns: 1fr;
    }
    
    .form-actions {
        flex-direction: column;
        gap: 1rem;
    }
    
    .contact-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .success-actions {
        flex-direction: column;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 0.75rem;
    }
    
    .hero-actions {
        flex-direction: column;
    }
    
    .courses-grid {
        grid-template-columns: 1fr;
    }
    
    .course-meta {
        flex-direction: column;
        align-items: flex-start;
        gap: 0.5rem;
    }
}

/* Focus Styles for Accessibility */
.btn:focus,
.nav-link:focus,
.form-input:focus,
.form-select:focus,
.form-textarea:focus,
.faq-question:focus {
    outline: 2px solid #2563eb;
    outline-offset: 2px;
}

/* Print Styles */
@media print {
    .header,
    .footer,
    .btn,
    .checkout-sidebar {
        display: none;
    }
    
    body {
        font-size: 12pt;
        line-height: 1.4;
    }
    
    .container {
        max-width: none;
        padding: 0;
    }
}