* {
    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: fixed;
    top: 0;
    width: 100%;
    z-index: 1000;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
    color: #6366f1;
    font-weight: 700;
    font-size: 1.2rem;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 30px;
    align-items: center;
}

.nav-link {
    text-decoration: none;
    color: #64748b;
    font-weight: 500;
    transition: color 0.3s ease;
    padding: 5px 0;
}

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

.nav-toggle {
    display: none;
    flex-direction: column;
    background: none;
    border: none;
    cursor: pointer;
    gap: 4px;
}

.nav-toggle span {
    width: 25px;
    height: 3px;
    background: #64748b;
    transition: 0.3s;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 12px 24px;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    text-align: center;
    transition: all 0.3s ease;
    border: 2px solid transparent;
    cursor: pointer;
    font-size: 16px;
}

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

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

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

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

.btn-outline {
    background: transparent;
    color: #6366f1;
    border-color: #e2e8f0;
    padding: 8px 16px;
    font-size: 14px;
}

.btn-outline:hover {
    border-color: #6366f1;
    background: #f8fafc;
}

.btn-large {
    padding: 16px 32px;
    font-size: 18px;
}

/* Hero Section */
.hero {
    margin-top: 70px;
    padding: 80px 0;
    background: linear-gradient(135deg, #f8fafc 0%, #e2e8f0 100%);
}

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

.hero-content h1 {
    font-size: 3.5rem;
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 20px;
    color: #1e293b;
}

.hero-content p {
    font-size: 1.2rem;
    color: #64748b;
    margin-bottom: 30px;
    line-height: 1.7;
}

.hero-cta {
    display: flex;
    gap: 20px;
}

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

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

.features h2 {
    text-align: center;
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 60px;
    color: #1e293b;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
}

.feature-card {
    text-align: center;
    padding: 40px 20px;
    border-radius: 12px;
    background: #f8fafc;
    transition: transform 0.3s ease;
}

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

.feature-icon {
    font-size: 3rem;
    margin-bottom: 20px;
}

.feature-card h3 {
    font-size: 1.3rem;
    font-weight: 600;
    margin-bottom: 15px;
    color: #1e293b;
}

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

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

.featured-courses h2 {
    text-align: center;
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 60px;
    color: #1e293b;
}

.courses-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 30px;
    margin-bottom: 50px;
}

.course-card {
    background: white;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 4px 20px rgba(0,0,0,0.08);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.course-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 30px rgba(0,0,0,0.12);
}

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

.course-content {
    padding: 25px;
}

.course-category {
    display: inline-block;
    background: #e0e7ff;
    color: #6366f1;
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 600;
    margin-bottom: 15px;
}

.course-content h3 {
    font-size: 1.3rem;
    font-weight: 600;
    margin-bottom: 12px;
    color: #1e293b;
}

.course-content p {
    color: #64748b;
    margin-bottom: 20px;
    line-height: 1.6;
}

.course-meta {
    display: flex;
    gap: 15px;
    margin-bottom: 20px;
}

.course-duration,
.course-level {
    font-size: 0.9rem;
    color: #64748b;
    padding: 4px 8px;
    background: #f1f5f9;
    border-radius: 6px;
}

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

.course-price {
    font-size: 1.4rem;
    font-weight: 700;
    color: #059669;
}

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

/* CTA Section */
.cta-section {
    padding: 80px 0;
    background: linear-gradient(135deg, #6366f1 0%, #8b5cf6 100%);
    color: white;
}

.cta-content {
    text-align: center;
}

.cta-content h2 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 20px;
}

.cta-content p {
    font-size: 1.2rem;
    margin-bottom: 30px;
    opacity: 0.9;
}

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

.cta-section .btn-primary:hover {
    background: #f8fafc;
    transform: translateY(-2px);
}

/* Footer */
.footer {
    background: #1e293b;
    color: #94a3b8;
    padding: 60px 0 20px;
}

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

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: 40px;
    margin-bottom: 40px;
}

.footer-section h3,
.footer-section h4 {
    color: white;
    margin-bottom: 20px;
    font-weight: 600;
}

.footer-section p {
    line-height: 1.6;
    margin-bottom: 15px;
}

.footer-contact a {
    color: #94a3b8;
    text-decoration: none;
}

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

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

.footer-section ul li {
    margin-bottom: 10px;
}

.footer-section ul li a {
    color: #94a3b8;
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-section ul li a:hover {
    color: white;
}

.footer-bottom {
    padding-top: 20px;
    border-top: 1px solid #334155;
    text-align: center;
}

/* Course Filters */
.course-filters {
    background: white;
    padding: 30px 0;
    margin-bottom: 40px;
    border-radius: 12px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
}

.filter-row {
    display: flex;
    gap: 20px;
    align-items: center;
    flex-wrap: wrap;
}

.search-box {
    flex: 1;
    min-width: 250px;
}

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

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

.filter-select {
    padding: 12px 16px;
    border: 2px solid #e2e8f0;
    border-radius: 8px;
    font-size: 16px;
    background: white;
    cursor: pointer;
    transition: border-color 0.3s ease;
}

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

/* Course Detail Page */
.course-header {
    margin-top: 70px;
    padding: 60px 0;
    background: linear-gradient(135deg, #1e293b 0%, #334155 100%);
    color: white;
}

.course-header-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 40px;
    align-items: start;
}

.course-title {
    font-size: 3rem;
    font-weight: 800;
    margin-bottom: 20px;
}

.course-subtitle {
    font-size: 1.3rem;
    opacity: 0.9;
    margin-bottom: 30px;
}

.course-stats {
    display: flex;
    gap: 30px;
    flex-wrap: wrap;
}

.stat-item {
    display: flex;
    flex-direction: column;
    gap: 5px;
}

.stat-label {
    font-size: 0.9rem;
    opacity: 0.8;
}

.stat-value {
    font-size: 1.1rem;
    font-weight: 600;
}

.course-cta-card {
    background: white;
    color: #333;
    padding: 30px;
    border-radius: 12px;
    text-align: center;
}

.course-price-large {
    font-size: 2.5rem;
    font-weight: 800;
    color: #059669;
    margin-bottom: 20px;
}

.course-detail-content {
    padding: 80px 0;
}

.course-detail-grid {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 60px;
}

.course-main h2 {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 20px;
    color: #1e293b;
}

.course-main h3 {
    font-size: 1.5rem;
    font-weight: 600;
    margin: 30px 0 15px;
    color: #1e293b;
}

.course-main p {
    line-height: 1.7;
    margin-bottom: 20px;
    color: #64748b;
}

.course-main ul {
    margin: 20px 0;
    padding-left: 20px;
}

.course-main ul li {
    margin-bottom: 10px;
    line-height: 1.6;
    color: #64748b;
}

.curriculum-list {
    list-style: none;
    padding: 0;
}

.curriculum-list li {
    padding: 15px;
    background: #f8fafc;
    margin-bottom: 10px;
    border-radius: 8px;
    border-left: 4px solid #6366f1;
}

.course-sidebar {
    position: sticky;
    top: 100px;
}

.sidebar-card {
    background: white;
    padding: 30px;
    border-radius: 12px;
    box-shadow: 0 4px 20px rgba(0,0,0,0.08);
    margin-bottom: 30px;
}

.sidebar-card h3 {
    margin-bottom: 20px;
    color: #1e293b;
}

.instructor-info {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.instructor-name {
    font-size: 1.2rem;
    font-weight: 600;
    color: #1e293b;
}

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

.faq-item {
    margin-bottom: 20px;
    padding: 20px;
    background: #f8fafc;
    border-radius: 8px;
}

.faq-question {
    font-weight: 600;
    margin-bottom: 10px;
    color: #1e293b;
}

.faq-answer {
    color: #64748b;
    line-height: 1.6;
}

/* Form Styles */
.form-group {
    margin-bottom: 20px;
}

.form-label {
    display: block;
    margin-bottom: 8px;
    font-weight: 600;
    color: #1e293b;
}

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

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

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

/* Page Content */
.page-content {
    margin-top: 70px;
    padding: 60px 0;
}

.page-header {
    text-align: center;
    margin-bottom: 50px;
}

.page-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 15px;
    color: #1e293b;
}

.page-subtitle {
    font-size: 1.2rem;
    color: #64748b;
}

.content-section {
    margin-bottom: 40px;
}

.content-section h2 {
    font-size: 1.8rem;
    font-weight: 600;
    margin-bottom: 15px;
    color: #1e293b;
}

.content-section h3 {
    font-size: 1.4rem;
    font-weight: 600;
    margin: 25px 0 10px;
    color: #1e293b;
}

.content-section p {
    line-height: 1.7;
    margin-bottom: 15px;
    color: #64748b;
}

.content-section ul {
    margin: 15px 0;
    padding-left: 20px;
}

.content-section ul li {
    margin-bottom: 8px;
    line-height: 1.6;
    color: #64748b;
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        top: 70px;
        left: -100%;
        width: 100%;
        height: calc(100vh - 70px);
        background: white;
        flex-direction: column;
        justify-content: start;
        padding-top: 50px;
        transition: left 0.3s ease;
        box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    }

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

    .nav-toggle {
        display: flex;
    }

    .hero-container {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 40px;
    }

    .hero-content h1 {
        font-size: 2.5rem;
    }

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

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

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

    .footer-content {
        grid-template-columns: 1fr;
        gap: 30px;
    }

    .course-header-content {
        grid-template-columns: 1fr;
        gap: 30px;
    }

    .course-detail-grid {
        grid-template-columns: 1fr;
        gap: 40px;
    }

    .course-sidebar {
        position: static;
    }

    .filter-row {
        flex-direction: column;
        align-items: stretch;
    }

    .search-box {
        min-width: auto;
    }
}

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

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

    .features h2,
    .featured-courses h2 {
        font-size: 2rem;
    }

    .course-title {
        font-size: 2rem;
    }

    .course-stats {
        gap: 20px;
    }

    .course-card {
        margin: 0 -5px;
    }
}