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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #fff;
}

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

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.3;
    margin-bottom: 1rem;
}

h1 {
    font-size: 2.5rem;
}

h2 {
    font-size: 2rem;
}

h3 {
    font-size: 1.5rem;
}

p {
    margin-bottom: 1rem;
}

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

a:hover {
    text-decoration: underline;
}

ul {
    list-style: none;
}

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

/* Buttons */
.btn {
    display: inline-block;
    padding: 12px 24px;
    border: none;
    border-radius: 6px;
    font-size: 1rem;
    font-weight: 500;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s ease;
    text-decoration: none;
}

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

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

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

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

/* Header */
.navbar {
    background-color: white;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    position: sticky;
    top: 0;
    z-index: 100;
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 20px;
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: 10px;
}

.logo {
    width: 40px;
    height: 40px;
}

.brand-text {
    font-size: 1.5rem;
    font-weight: 700;
    color: #2563eb;
}

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

.nav-link {
    color: #64748b;
    font-weight: 500;
    transition: color 0.3s ease;
}

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

/* Hero Section */
.hero {
    background: linear-gradient(135deg, #f8fafc 0%, #e2e8f0 100%);
    padding: 80px 0;
}

.hero .container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.hero-content h1 {
    font-size: 3rem;
    margin-bottom: 1.5rem;
    color: #1e293b;
}

.hero-content p {
    font-size: 1.2rem;
    color: #64748b;
    margin-bottom: 2rem;
}

.hero-image img {
    width: 100%;
    height: auto;
}

/* Page Header */
.page-header {
    background: linear-gradient(135deg, #2563eb 0%, #1d4ed8 100%);
    color: white;
    padding: 60px 0;
    text-align: center;
}

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

.page-header p {
    font-size: 1.2rem;
    opacity: 0.9;
}

/* Courses Grid */
.featured-courses,
.courses-catalog {
    padding: 80px 0;
}

.featured-courses h2,
.courses-catalog h2 {
    text-align: center;
    margin-bottom: 3rem;
}

.courses-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
    margin-bottom: 3rem;
}

.course-card {
    background: white;
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    overflow: hidden;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.course-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 25px rgba(0,0,0,0.15);
}

.course-image {
    height: 200px;
    overflow: hidden;
}

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

.course-content {
    padding: 1.5rem;
}

.course-meta {
    display: flex;
    gap: 1rem;
    margin-bottom: 1rem;
    font-size: 0.9rem;
    color: #64748b;
}

.course-title {
    font-size: 1.3rem;
    margin-bottom: 0.5rem;
}

.course-title a {
    color: #1e293b;
    text-decoration: none;
}

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

.course-description {
    color: #64748b;
    margin-bottom: 1rem;
    line-height: 1.5;
}

.course-footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: 1.5rem;
}

.course-price {
    font-size: 1.5rem;
    font-weight: 700;
    color: #2563eb;
}

.course-tag {
    background: #e0f2fe;
    color: #0277bd;
    padding: 4px 8px;
    border-radius: 4px;
    font-size: 0.8rem;
    font-weight: 500;
}

/* Filters */
.filters-bar {
    display: flex;
    gap: 1rem;
    margin-bottom: 2rem;
    align-items: center;
    flex-wrap: wrap;
}

.search-box input {
    padding: 12px 16px;
    border: 2px solid #e2e8f0;
    border-radius: 6px;
    font-size: 1rem;
    min-width: 300px;
}

.filter-group {
    display: flex;
    gap: 1rem;
}

.filter-group select {
    padding: 12px 16px;
    border: 2px solid #e2e8f0;
    border-radius: 6px;
    font-size: 1rem;
    background: white;
}

/* Course Detail */
.course-detail {
    padding: 40px 0;
}

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

.course-detail-content h1 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

.course-detail-meta {
    display: flex;
    gap: 2rem;
    margin: 2rem 0;
    padding: 1.5rem;
    background: #f8fafc;
    border-radius: 8px;
}

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

.meta-label {
    font-size: 0.9rem;
    color: #64748b;
    display: block;
}

.meta-value {
    font-weight: 600;
    color: #1e293b;
    font-size: 1.1rem;
}

.course-sidebar {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    height: fit-content;
    position: sticky;
    top: 100px;
}

.course-sidebar img {
    width: 100%;
    border-radius: 8px;
    margin-bottom: 1.5rem;
}

.sidebar-price {
    font-size: 2rem;
    font-weight: 700;
    color: #2563eb;
    text-align: center;
    margin-bottom: 1.5rem;
}

.curriculum-list,
.learning-list {
    margin: 2rem 0;
}

.curriculum-list li,
.learning-list li {
    padding: 0.5rem 0;
    border-bottom: 1px solid #e2e8f0;
}

.learning-list li:before {
    content: "✓";
    color: #10b981;
    font-weight: bold;
    margin-right: 0.5rem;
}

.instructor-info {
    margin: 2rem 0;
    padding: 1.5rem;
    background: #f8fafc;
    border-radius: 8px;
}

.faq-section {
    margin: 3rem 0;
}

.faq-item {
    border-bottom: 1px solid #e2e8f0;
    padding: 1rem 0;
}

.faq-question {
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.faq-question:after {
    content: "+";
    font-size: 1.5rem;
    color: #64748b;
}

.faq-item.active .faq-question:after {
    content: "−";
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
    padding-top: 1rem;
    color: #64748b;
}

/* Features */
.features {
    background: #f8fafc;
    padding: 80px 0;
}

.features h2 {
    text-align: center;
    margin-bottom: 3rem;
}

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

.feature-card {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    text-align: center;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.feature-card h3 {
    color: #2563eb;
    margin-bottom: 1rem;
}

/* Checkout */
.checkout {
    padding: 40px 0;
}

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

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

.step {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    border-radius: 20px;
    background: #f1f5f9;
    color: #64748b;
}

.step.active {
    background: #2563eb;
    color: white;
}

.step.completed {
    background: #10b981;
    color: white;
}

.step-number {
    width: 24px;
    height: 24px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.9rem;
    font-weight: 600;
}

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

.checkout-form {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

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

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

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

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 12px 16px;
    border: 2px solid #e2e8f0;
    border-radius: 6px;
    font-size: 1rem;
    transition: border-color 0.3s ease;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: #2563eb;
}

.checkbox-label {
    display: flex;
    align-items: flex-start;
    gap: 0.5rem;
    cursor: pointer;
}

.checkbox-label input[type="checkbox"] {
    width: auto;
    margin: 0;
}

.order-summary {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    height: fit-content;
    position: sticky;
    top: 100px;
}

.summary-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 0;
    border-bottom: 1px solid #e2e8f0;
}

.summary-total {
    font-weight: 700;
    font-size: 1.2rem;
    color: #2563eb;
}

.payment-security {
    text-align: center;
    margin-bottom: 2rem;
    padding: 1.5rem;
    background: #f0f9ff;
    border-radius: 8px;
}

.security-badges {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 1rem;
}

/* Order Success */
.order-success {
    padding: 80px 0;
    text-align: center;
}

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

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

.order-details {
    background: #f8fafc;
    padding: 2rem;
    border-radius: 12px;
    margin: 2rem 0;
    text-align: left;
}

.success-actions {
    display: flex;
    gap: 1rem;
    justify-content: center;
    margin-top: 2rem;
}

/* About Page */
.about-content {
    padding: 60px 0;
}

.about-grid {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 3rem;
    align-items: center;
}

.about-text ul {
    list-style: disc;
    margin-left: 2rem;
}

.team-section {
    background: #f8fafc;
    padding: 60px 0;
}

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

.team-member {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    text-align: center;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.role {
    color: #2563eb;
    font-weight: 600;
    margin-bottom: 1rem;
}

/* Contact Page */
.contact-content {
    padding: 60px 0;
}

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

.contact-form {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

.contact-info {
    background: #f8fafc;
    padding: 2rem;
    border-radius: 12px;
}

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

.contact-item h3 {
    color: #2563eb;
    margin-bottom: 0.5rem;
}

/* FAQ Page */
.faq-content {
    padding: 60px 0;
}

.faq-list {
    max-width: 800px;
    margin: 0 auto 3rem;
}

.faq-contact {
    text-align: center;
    padding: 3rem;
    background: #f8fafc;
    border-radius: 12px;
    max-width: 600px;
    margin: 0 auto;
}

/* Legal Pages */
.legal-content {
    padding: 60px 0;
}

.legal-text {
    max-width: 800px;
    margin: 0 auto;
}

.legal-text h2 {
    color: #2563eb;
    margin-top: 2rem;
    margin-bottom: 1rem;
}

.legal-text ul {
    list-style: disc;
    margin-left: 2rem;
    margin-bottom: 1rem;
}

/* Footer */
footer {
    background: #1e293b;
    color: white;
    padding: 60px 0 20px;
    margin-top: auto;
}

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

.footer-section h4 {
    color: #2563eb;
    margin-bottom: 1rem;
}

.footer-section ul {
    list-style: none;
}

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

.footer-section a {
    color: #cbd5e1;
    transition: color 0.3s ease;
}

.footer-section a:hover {
    color: white;
    text-decoration: none;
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid #374151;
    color: #cbd5e1;
}

/* Utility Classes */
.text-center {
    text-align: center;
}

.mt-2 { margin-top: 1rem; }
.mb-2 { margin-bottom: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mb-3 { margin-bottom: 1.5rem; }

/* Responsive Design */
@media (max-width: 768px) {
    .hero .container {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .hero-content h1 {
        font-size: 2rem;
    }
    
    .nav-menu {
        display: none;
    }
    
    .courses-grid {
        grid-template-columns: 1fr;
    }
    
    .course-detail-grid,
    .checkout-content,
    .about-grid,
    .contact-grid {
        grid-template-columns: 1fr;
    }
    
    .filters-bar {
        flex-direction: column;
        align-items: stretch;
    }
    
    .search-box input {
        min-width: auto;
        width: 100%;
    }
    
    .form-row {
        grid-template-columns: 1fr;
    }
    
    .success-actions {
        flex-direction: column;
        align-items: center;
    }
    
    .checkout-steps {
        flex-direction: column;
        align-items: center;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }
    
    .hero {
        padding: 40px 0;
    }
    
    .page-header {
        padding: 40px 0;
    }
    
    .page-header h1 {
        font-size: 2rem;
    }
    
    .featured-courses,
    .courses-catalog {
        padding: 40px 0;
    }
    
    .course-card {
        margin-bottom: 1rem;
    }
    
    .checkout-form,
    .order-summary {
        padding: 1rem;
    }
}

/* Focus States for Accessibility */
button:focus,
input:focus,
select:focus,
textarea:focus,
a:focus {
    outline: 2px solid #2563eb;
    outline-offset: 2px;
}

/* Loading States */
.loading {
    opacity: 0.6;
    pointer-events: none;
}

/* Error States */
.error {
    border-color: #ef4444 !important;
}

.error-message {
    color: #ef4444;
    font-size: 0.9rem;
    margin-top: 0.5rem;
}

/* Success States */
.success {
    border-color: #10b981 !important;
}

.success-message {
    color: #10b981;
    font-size: 0.9rem;
    margin-top: 0.5rem;
}