* {
    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: 100;
}

.nav {
    padding: 1rem 0;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

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

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

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

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

.nav-link {
    text-decoration: none;
    color: #666;
    font-weight: 500;
    transition: color 0.3s ease;
    padding: 0.5rem 0;
}

.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: 2px 0;
    transition: 0.3s;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 12px 24px;
    text-decoration: none;
    border-radius: 8px;
    font-weight: 600;
    text-align: center;
    transition: all 0.3s ease;
    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;
}

.btn-small {
    padding: 8px 16px;
    font-size: 0.9rem;
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, #f8fafc 0%, #e2e8f0 100%);
    padding: 80px 0;
    min-height: 600px;
    display: flex;
    align-items: center;
}

.hero-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.hero-text h1 {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
    color: #1e293b;
    line-height: 1.2;
}

.hero-text p {
    font-size: 1.25rem;
    color: #64748b;
    margin-bottom: 2rem;
    line-height: 1.6;
}

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

.hero-image img {
    width: 100%;
    height: auto;
    border-radius: 12px;
}

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

.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(250px, 1fr));
    gap: 2rem;
}

.feature {
    text-align: center;
    padding: 2rem;
    border-radius: 12px;
    background: #f8fafc;
    transition: transform 0.3s ease;
}

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

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

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

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

/* Featured Courses Section */
.featured-courses {
    padding: 80px 0;
    background: #f8fafc;
}

.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 20px rgba(0,0,0,0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.course-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 30px rgba(0,0,0,0.15);
}

.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: 0.8rem;
    font-weight: 500;
}

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

.course-difficulty {
    background: #f0fdf4;
    color: #16a34a;
}

.course-content h3 {
    margin-bottom: 0.75rem;
}

.course-content h3 a {
    text-decoration: none;
    color: #1e293b;
    font-size: 1.25rem;
    font-weight: 600;
}

.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: 1rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid #e2e8f0;
}

.course-duration {
    color: #64748b;
    font-size: 0.9rem;
}

.course-price {
    font-size: 1.25rem;
    font-weight: 700;
    color: #16a34a;
}

.course-instructor {
    margin-bottom: 1rem;
    font-size: 0.9rem;
    color: #64748b;
}

/* Search and Filter */
.search-filter {
    padding: 2rem 0;
    background: white;
    border-bottom: 1px solid #e2e8f0;
}

.search-container {
    display: flex;
    gap: 1rem;
    max-width: 800px;
    margin: 0 auto;
}

.search-input {
    flex: 1;
    padding: 12px 16px;
    border: 2px solid #e2e8f0;
    border-radius: 8px;
    font-size: 1rem;
}

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

.category-filter {
    padding: 12px 16px;
    border: 2px solid #e2e8f0;
    border-radius: 8px;
    font-size: 1rem;
    background: white;
    cursor: pointer;
}

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

/* Course Detail Page */
.course-hero {
    background: linear-gradient(135deg, #6366f1 0%, #8b5cf6 100%);
    color: white;
    padding: 60px 0;
}

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

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

.course-hero-meta {
    display: flex;
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.course-hero-meta span {
    padding: 0.5rem 1rem;
    background: rgba(255,255,255,0.2);
    border-radius: 20px;
    font-size: 0.9rem;
}

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

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

.course-price-large {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.course-details-list {
    list-style: none;
    margin-bottom: 2rem;
}

.course-details-list li {
    padding: 0.5rem 0;
    border-bottom: 1px solid rgba(255,255,255,0.2);
    display: flex;
    justify-content: space-between;
}

.course-main {
    padding: 60px 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: #374151;
}

.course-section ul {
    list-style-position: inside;
    color: #64748b;
    line-height: 1.8;
}

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

.curriculum-list {
    list-style: none;
}

.curriculum-item {
    padding: 1rem;
    border: 1px solid #e2e8f0;
    border-radius: 8px;
    margin-bottom: 0.5rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.instructor-card {
    background: #f8fafc;
    padding: 2rem;
    border-radius: 12px;
    margin-bottom: 2rem;
}

.instructor-name {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: #1e293b;
}

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

.faq-question {
    background: #f8fafc;
    padding: 1rem;
    cursor: pointer;
    font-weight: 600;
    border: none;
    width: 100%;
    text-align: left;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

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

.faq-answer {
    padding: 1rem;
    display: none;
    color: #64748b;
    line-height: 1.6;
}

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

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

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

.form-input,
.form-textarea,
.form-select {
    width: 100%;
    padding: 12px 16px;
    border: 2px solid #e2e8f0;
    border-radius: 8px;
    font-size: 1rem;
    transition: border-color 0.3s ease;
}

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

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

/* Footer */
.footer {
    background: #1e293b;
    color: white;
    padding: 60px 0 20px;
}

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

.footer-section h3 {
    margin-bottom: 1rem;
    color: #f1f5f9;
}

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

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

.footer-section a {
    color: #cbd5e1;
    text-decoration: none;
    transition: color 0.3s ease;
}

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

.footer-brand {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 1rem;
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid #374151;
    color: #94a3b8;
}

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

.hidden {
    display: none;
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background-color: white;
        width: 100%;
        text-align: center;
        transition: 0.3s;
        box-shadow: 0 10px 27px rgba(0,0,0,0.05);
        padding: 2rem 0;
    }

    .nav-menu.active {
        left: 0;
    }

    .nav-toggle {
        display: flex;
    }

    .hero-content {
        grid-template-columns: 1fr;
        gap: 2rem;
        text-align: center;
    }

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

    .hero-buttons {
        justify-content: center;
        flex-wrap: wrap;
    }

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

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

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

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

    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
}

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

    .hero {
        padding: 40px 0;
    }

    .hero-text h1 {
        font-size: 1.75rem;
    }

    .features,
    .featured-courses {
        padding: 40px 0;
    }

    .btn {
        padding: 10px 20px;
        font-size: 0.9rem;
    }
}