* {
    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;
}

/* Header */
.header {
    background: #fff;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.nav {
    padding: 1rem 0;
}

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

.nav-brand {
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
    color: #333;
}

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

.brand-text {
    font-size: 1.5rem;
    font-weight: 700;
    color: #6366f1;
}

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

.nav-link {
    text-decoration: none;
    color: #333;
    font-weight: 500;
    transition: color 0.3s;
}

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

.nav-toggle {
    display: none;
    flex-direction: column;
    background: none;
    border: none;
    cursor: pointer;
    padding: 5px;
}

.nav-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: 5rem 0;
    text-align: center;
}

.hero h1 {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 1rem;
}

.hero p {
    font-size: 1.2rem;
    margin-bottom: 2rem;
    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: 12px 24px;
    text-decoration: none;
    border-radius: 6px;
    font-weight: 600;
    text-align: center;
    transition: all 0.3s;
    border: none;
    cursor: pointer;
    font-size: 1rem;
}

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

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

.btn-secondary {
    background: transparent;
    color: #6366f1;
    border: 2px solid #6366f1;
}

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

.hero .btn-secondary {
    color: white;
    border-color: white;
}

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

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

.features h2 {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
    color: #1f2937;
}

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

.feature-card {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    text-align: center;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    transition: transform 0.3s;
}

.feature-card:hover {
    transform: translateY(-5px);
}

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

.feature-card h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: #1f2937;
}

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

.featured-courses h2 {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
    color: #1f2937;
}

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

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

.course-card:hover {
    transform: translateY(-5px);
}

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

.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: #ddd6fe;
    color: #6366f1;
}

.course-difficulty {
    background: #d1fae5;
    color: #059669;
}

.course-card h3 {
    font-size: 1.25rem;
    margin-bottom: 0.75rem;
    color: #1f2937;
}

.course-card p {
    color: #6b7280;
    margin-bottom: 1rem;
}

.course-info {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
    font-weight: 500;
}

.course-duration {
    color: #6b7280;
}

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

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

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

.search-input {
    padding: 12px 16px;
    border: 2px solid #e5e7eb;
    border-radius: 6px;
    font-size: 1rem;
    min-width: 300px;
}

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

.filter-select {
    padding: 12px 16px;
    border: 2px solid #e5e7eb;
    border-radius: 6px;
    font-size: 1rem;
    background: white;
}

/* Course Detail Page */
.course-header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 3rem 0;
}

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

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

.course-main h2 {
    color: #1f2937;
    margin-bottom: 1.5rem;
}

.course-sidebar {
    background: #f8fafc;
    padding: 2rem;
    border-radius: 12px;
    height: fit-content;
}

.instructor-info {
    margin-top: 2rem;
    padding-top: 2rem;
    border-top: 1px solid #e5e7eb;
}

.curriculum-list,
.requirements-list,
.learning-list {
    list-style: none;
    margin-bottom: 2rem;
}

.curriculum-list li,
.requirements-list li,
.learning-list li {
    padding: 0.5rem 0;
    border-bottom: 1px solid #e5e7eb;
}

.curriculum-list li:before {
    content: "📚 ";
    margin-right: 0.5rem;
}

.requirements-list li:before {
    content: "✓ ";
    margin-right: 0.5rem;
    color: #059669;
}

.learning-list li:before {
    content: "🎯 ";
    margin-right: 0.5rem;
}

/* FAQ */
.faq-section {
    padding: 3rem 0;
}

.faq-item {
    background: white;
    border: 1px solid #e5e7eb;
    border-radius: 6px;
    margin-bottom: 1rem;
}

.faq-question {
    width: 100%;
    padding: 1rem;
    background: none;
    border: none;
    text-align: left;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.faq-answer {
    padding: 0 1rem 1rem;
    display: none;
}

.faq-answer.active {
    display: block;
}

/* Contact Form */
.contact-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-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: #1f2937;
}

.form-group input,
.form-group textarea,
.form-group select {
    width: 100%;
    padding: 12px;
    border: 2px solid #e5e7eb;
    border-radius: 6px;
    font-size: 1rem;
}

.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;
}

/* Footer */
.footer {
    background: #1f2937;
    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-section h3,
.footer-section h4 {
    margin-bottom: 1rem;
    color: #6366f1;
}

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

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

.footer-section a {
    color: #d1d5db;
    text-decoration: none;
    transition: color 0.3s;
}

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

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid #374151;
    color: #9ca3af;
}

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

.hidden {
    display: none;
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-menu {
        display: none;
        flex-direction: column;
        position: absolute;
        top: 100%;
        left: 0;
        width: 100%;
        background: white;
        box-shadow: 0 2px 10px rgba(0,0,0,0.1);
        padding: 1rem;
    }

    .nav-menu.active {
        display: flex;
    }

    .nav-toggle {
        display: flex;
    }

    .hero h1 {
        font-size: 2rem;
    }

    .hero-actions {
        flex-direction: column;
        align-items: center;
    }

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

    .search-controls {
        flex-direction: column;
    }

    .search-input {
        min-width: auto;
        width: 100%;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }

    .hero {
        padding: 3rem 0;
    }

    .features,
    .featured-courses {
        padding: 3rem 0;
    }

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