* {
    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: #fff;
}

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

/* Header */
.header {
    background: #fff;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem 0;
}

.logo a {
    display: flex;
    align-items: center;
    text-decoration: none;
    color: #6366f1;
    font-weight: 700;
    font-size: 1.25rem;
    gap: 0.5rem;
}

.nav ul {
    display: flex;
    list-style: none;
    gap: 2rem;
    align-items: center;
}

.nav a {
    text-decoration: none;
    color: #64748b;
    font-weight: 500;
    transition: color 0.2s;
}

.nav a:hover,
.nav a.active {
    color: #6366f1;
}

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

.mobile-menu-toggle span {
    width: 25px;
    height: 3px;
    background: #333;
    margin: 3px 0;
    transition: 0.3s;
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 6rem 0;
    text-align: center;
}

.hero-content h1 {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
    line-height: 1.2;
}

.hero-content p {
    font-size: 1.25rem;
    margin-bottom: 2.5rem;
    opacity: 0.9;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.hero-actions {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 0.75rem 2rem;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.2s;
    border: 2px solid transparent;
    cursor: pointer;
    text-align: center;
}

.btn-primary {
    background: #6366f1;
    color: white;
}

.btn-primary:hover {
    background: #5855eb;
    transform: translateY(-2px);
}

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

.btn-secondary:hover {
    background: white;
    color: #6366f1;
}

.btn-outline {
    background: transparent;
    color: #6366f1;
    border-color: #6366f1;
}

.btn-outline:hover {
    background: #6366f1;
    color: white;
}

/* Features Section */
.features {
    padding: 5rem 0;
    background: #f8fafc;
}

.features h2 {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
    color: #1e293b;
}

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

.feature-card {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    text-align: center;
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
    transition: transform 0.2s, box-shadow 0.2s;
}

.feature-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 25px rgba(0,0,0,0.1);
}

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

.feature-card h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: #1e293b;
}

.feature-card p {
    color: #64748b;
    line-height: 1.6;
}

/* Featured Courses */
.featured-courses {
    padding: 5rem 0;
}

.featured-courses h2 {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
    color: #1e293b;
}

.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;
    overflow: hidden;
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
    transition: transform 0.2s, box-shadow 0.2s;
}

.course-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 30px rgba(0,0,0,0.1);
}

.course-image {
    position: relative;
    overflow: hidden;
}

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

.course-badge {
    position: absolute;
    top: 1rem;
    right: 1rem;
    background: #ef4444;
    color: white;
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.875rem;
    font-weight: 600;
}

.course-badge:contains("New") {
    background: #10b981;
}

.course-badge:contains("Featured") {
    background: #f59e0b;
}

.course-content {
    padding: 1.5rem;
}

.course-meta {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 1rem;
}

.course-category,
.course-difficulty {
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.875rem;
    font-weight: 500;
}

.course-category {
    background: #e0e7ff;
    color: #6366f1;
}

.course-difficulty {
    background: #f0f9ff;
    color: #0ea5e9;
}

.course-content h3 {
    margin-bottom: 0.75rem;
    font-size: 1.25rem;
    line-height: 1.4;
}

.course-content h3 a {
    color: #1e293b;
    text-decoration: none;
}

.course-content h3 a:hover {
    color: #6366f1;
}

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

.course-details {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1.5rem;
    padding-top: 1rem;
    border-top: 1px solid #e2e8f0;
}

.course-duration {
    color: #64748b;
    font-size: 0.875rem;
}

.course-price {
    font-size: 1.25rem;
    font-weight: 700;
    color: #6366f1;
}

.course-actions {
    display: flex;
    gap: 0.5rem;
}

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

/* Trust Section */
.trust-section {
    padding: 5rem 0;
    background: #f8fafc;
}

.trust-section h2 {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
    color: #1e293b;
}

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

.trust-item {
    text-align: center;
    padding: 2rem;
}

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

.trust-item h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: #1e293b;
}

.trust-item p {
    color: #64748b;
    line-height: 1.6;
}

/* Footer */
.footer {
    background: #1e293b;
    color: white;
    padding: 3rem 0 1rem;
}

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

.footer-logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 1rem;
    font-weight: 700;
    font-size: 1.25rem;
}

.footer-section h4 {
    margin-bottom: 1rem;
    color: #f1f5f9;
}

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

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

.footer-section a {
    color: #cbd5e1;
    text-decoration: none;
    transition: color 0.2s;
}

.footer-section a:hover {
    color: #6366f1;
}

.footer-section p {
    color: #cbd5e1;
    line-height: 1.6;
    margin-bottom: 0.5rem;
}

.footer-bottom {
    border-top: 1px solid #334155;
    padding-top: 2rem;
    text-align: center;
    color: #94a3b8;
}

/* Search and Filter */
.search-filter {
    background: #f8fafc;
    padding: 2rem 0;
    margin-bottom: 3rem;
}

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

.search-box {
    flex: 1;
    min-width: 300px;
}

.search-box input {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 2px solid #e2e8f0;
    border-radius: 8px;
    font-size: 1rem;
    transition: border-color 0.2s;
}

.search-box input:focus {
    outline: none;
    border-color: #6366f1;
}

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

.filter-select {
    padding: 0.75rem 1rem;
    border: 2px solid #e2e8f0;
    border-radius: 8px;
    background: white;
    font-size: 1rem;
    cursor: pointer;
    transition: border-color 0.2s;
}

.filter-select:focus {
    outline: none;
    border-color: #6366f1;
}

/* Course Detail Page */
.course-header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 4rem 0;
}

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

.course-info h1 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    line-height: 1.2;
}

.course-info p {
    font-size: 1.125rem;
    margin-bottom: 2rem;
    opacity: 0.9;
}

.course-meta-detail {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
    margin-bottom: 2rem;
}

.course-meta-detail span {
    background: rgba(255,255,255,0.2);
    padding: 0.5rem 1rem;
    border-radius: 20px;
    font-size: 0.875rem;
}

.course-sidebar {
    background: rgba(255,255,255,0.1);
    padding: 2rem;
    border-radius: 12px;
    backdrop-filter: blur(10px);
}

.course-price-large {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 1rem;
}

.course-details-main {
    padding: 5rem 0;
}

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

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

.course-section h2 {
    font-size: 2rem;
    margin-bottom: 1.5rem;
    color: #1e293b;
}

.course-section h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: #1e293b;
}

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

.course-section li {
    padding: 0.5rem 0;
    border-bottom: 1px solid #e2e8f0;
    position: relative;
    padding-left: 1.5rem;
}

.course-section li:before {
    content: "✓";
    position: absolute;
    left: 0;
    color: #10b981;
    font-weight: bold;
}

.curriculum-item {
    background: #f8fafc;
    padding: 1rem;
    border-radius: 8px;
    margin-bottom: 0.5rem;
    border-left: 4px solid #6366f1;
}

.faq-item {
    margin-bottom: 1.5rem;
    border: 1px solid #e2e8f0;
    border-radius: 8px;
    overflow: hidden;
}

.faq-question {
    background: #f8fafc;
    padding: 1rem;
    cursor: pointer;
    font-weight: 600;
    transition: background 0.2s;
}

.faq-question:hover {
    background: #f1f5f9;
}

.faq-answer {
    padding: 1rem;
    background: white;
    border-top: 1px solid #e2e8f0;
}

.instructor-card {
    background: #f8fafc;
    padding: 2rem;
    border-radius: 12px;
    text-align: center;
}

.instructor-card h4 {
    font-size: 1.25rem;
    margin-bottom: 0.5rem;
    color: #1e293b;
}

.instructor-card p {
    color: #64748b;
    line-height: 1.6;
}

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

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: #374151;
}

.form-group input,
.form-group textarea,
.form-group select {
    width: 100%;
    padding: 0.75rem;
    border: 2px solid #e5e7eb;
    border-radius: 8px;
    font-size: 1rem;
    transition: border-color 0.2s;
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
    outline: none;
    border-color: #6366f1;
}

.form-group textarea {
    resize: vertical;
    min-height: 120px;
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav {
        display: none;
    }
    
    .mobile-menu-toggle {
        display: flex;
    }
    
    .hero-content h1 {
        font-size: 2rem;
    }
    
    .hero-content p {
        font-size: 1rem;
    }
    
    .hero-actions {
        flex-direction: column;
        align-items: center;
    }
    
    .courses-grid {
        grid-template-columns: 1fr;
    }
    
    .course-hero {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .course-content-grid {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .search-filter-content {
        flex-direction: column;
        align-items: stretch;
    }
    
    .search-box {
        min-width: auto;
    }
    
    .filter-group {
        justify-content: stretch;
    }
    
    .filter-select {
        flex: 1;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }
    
    .hero {
        padding: 4rem 0;
    }
    
    .features,
    .featured-courses,
    .trust-section {
        padding: 3rem 0;
    }
    
    .features h2,
    .featured-courses h2,
    .trust-section h2 {
        font-size: 2rem;
    }
    
    .feature-card,
    .trust-item {
        padding: 1.5rem;
    }
    
    .course-header {
        padding: 3rem 0;
    }
    
    .course-details-main {
        padding: 3rem 0;
    }
}