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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.7;
    color: #2D3748;
    background-color: #FAFBFC;
    font-weight: 400;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 16px;
}

/* Typography */
h1, h2, h3, h4 {
    font-weight: 600;
    color: #1A202C;
    letter-spacing: -0.025em;
}

h1 {
    font-size: 2.75rem;
    line-height: 1.1;
    font-weight: 700;
}

h2 {
    font-size: 2.25rem;
    line-height: 1.2;
    font-weight: 600;
}

h3 {
    font-size: 1.5rem;
    line-height: 1.3;
    font-weight: 600;
}

h4 {
    font-size: 1.125rem;
    line-height: 1.4;
    font-weight: 500;
}

p {
    color: #4A5568;
    font-size: 1rem;
    line-height: 1.6;
}

/* Navigation */
.navbar {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(226, 232, 240, 0.8);
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 1000;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 72px;
}

.nav-logo h1 {
    font-size: 1.5rem;
    color: #1E40AF;
    font-weight: 600;
    letter-spacing: -0.025em;
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: 40px;
}

.nav-link {
    text-decoration: none;
    color: #4A5568;
    font-weight: 500;
    font-size: 0.95rem;
    transition: all 0.2s ease;
    position: relative;
}

.nav-link:hover {
    color: #1E40AF;
}

.nav-link::after {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    bottom: -4px;
    left: 0;
    background: #1E40AF;
    transition: width 0.2s ease;
}

.nav-link:hover::after {
    width: 100%;
}

.nav-toggle {
    display: none;
    flex-direction: column;
    cursor: pointer;
}

.nav-toggle span {
    width: 25px;
    height: 3px;
    background: #1E293B;
    margin: 3px 0;
    transition: 0.3s;
}

/* Buttons */
.btn-primary, .btn-secondary {
    border: none;
    border-radius: 8px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s ease;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: 0.95rem;
    letter-spacing: 0.025em;
}

.btn-primary {
    background: linear-gradient(135deg, #2563EB 0%, #1D4ED8 100%);
    color: #FFFFFF;
    padding: 12px 28px;
    box-shadow: 0 4px 14px rgba(37, 99, 235, 0.2);
}

.btn-primary:hover {
    background: linear-gradient(135deg, #1D4ED8 0%, #1E3A8A 100%);
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(37, 99, 235, 0.3);
}

.btn-secondary {
    background: #FFFFFF;
    color: #2563EB;
    border: 1.5px solid #DBEAFE;
    padding: 11px 27px;
}

.btn-secondary:hover {
    background: #EFF6FF;
    border-color: #2563EB;
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(37, 99, 235, 0.15);
}

.btn-primary.large, .btn-secondary.large {
    padding: 16px 32px;
    font-size: 1.1rem;
}

.btn-primary.full-width {
    width: 100%;
    padding: 14px;
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, #DBEAFE 0%, #EFF6FF 50%, #F0F9FF 100%);
    padding: 120px 0 100px;
    margin-top: 72px;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><defs><pattern id="grain" width="100" height="100" patternUnits="userSpaceOnUse"><circle cx="25" cy="25" r="1" fill="rgba(59,130,246,0.02)"/><circle cx="75" cy="75" r="1" fill="rgba(16,185,129,0.02)"/><circle cx="50" cy="10" r="0.5" fill="rgba(59,130,246,0.03)"/><circle cx="20" cy="80" r="0.5" fill="rgba(16,185,129,0.03)"/></pattern></defs><rect width="100" height="100" fill="url(%23grain)"/></svg>') repeat;
    pointer-events: none;
}

.hero-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 80px;
    align-items: center;
    position: relative;
    z-index: 1;
}

.hero-title {
    font-size: 3.25rem;
    font-weight: 700;
    color: #1A202C;
    margin-bottom: 24px;
    line-height: 1.1;
    letter-spacing: -0.03em;
}

.hero-subtitle {
    font-size: 1.125rem;
    color: #4A5568;
    margin-bottom: 40px;
    line-height: 1.7;
    font-weight: 400;
}

.hero-buttons {
    display: flex;
    gap: 16px;
    margin-bottom: 48px;
}

.hero-stats {
    display: flex;
    gap: 48px;
}

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

.stat-item h3 {
    font-size: 2rem;
    color: #1E40AF;
    font-weight: 700;
    margin-bottom: 4px;
    letter-spacing: -0.025em;
}

.stat-item p {
    color: #4A5568;
    font-size: 0.875rem;
    font-weight: 500;
}

/* Hero Illustration */
.hero-illustration {
    position: relative;
    height: 450px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.illustration-circle {
    width: 350px;
    height: 350px;
    background: linear-gradient(135deg, rgba(37, 99, 235, 0.1) 0%, rgba(29, 78, 216, 0.08) 100%);
    border-radius: 50%;
    position: absolute;
    filter: blur(1px);
}

.illustration-person {
    width: 180px;
    height: 220px;
    background: linear-gradient(135deg, #2563EB 0%, #1D4ED8 100%);
    border-radius: 90px 90px 20px 20px;
    position: relative;
    z-index: 2;
    opacity: 0.9;
}

.illustration-book {
    width: 70px;
    height: 50px;
    background: linear-gradient(135deg, #3B82F6 0%, #2563EB 100%);
    border-radius: 6px;
    position: absolute;
    bottom: 80px;
    right: 50px;
    z-index: 3;
    opacity: 0.9;
}

/* Section Styles */
.section-header {
    text-align: center;
    margin-bottom: 64px;
}

.section-title {
    margin-bottom: 16px;
}

.section-subtitle {
    font-size: 1.125rem;
    color: #4A5568;
    max-width: 640px;
    margin: 0 auto;
    font-weight: 400;
    line-height: 1.6;
}

/* Features Section */
.features {
    padding: 100px 0;
    background: #FFFFFF;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 40px;
}

.feature-card {
    background: #FFFFFF;
    padding: 40px 32px;
    border-radius: 12px;
    text-align: center;
    border: 1px solid #E2E8F0;
    transition: all 0.2s ease;
    position: relative;
    overflow: hidden;
}

.feature-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, #2563EB 0%, #3B82F6 100%);
    transform: translateX(-100%);
    transition: transform 0.3s ease;
}

.feature-card:hover::before {
    transform: translateX(0);
}

.feature-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.08);
    border-color: #CBD5E0;
}

.feature-icon {
    width: 56px;
    height: 56px;
    background: linear-gradient(135deg, #DBEAFE 0%, #EFF6FF 100%);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 24px;
}

.feature-icon i {
    color: #1E40AF;
    font-size: 20px;
}

.feature-card h3 {
    margin-bottom: 16px;
    color: #1A202C;
    font-size: 1.25rem;
}

.feature-card p {
    color: #4A5568;
    line-height: 1.7;
    font-size: 0.95rem;
}

/* Courses Section */
.courses {
    padding: 120px 0 100px 0;
    background: #FAFBFC;
}

.courses-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 32px;
}

.course-card {
    background: #FFFFFF;
    border-radius: 12px;
    overflow: visible;
    border: 1px solid #E2E8F0;
    transition: all 0.2s ease;
    position: relative;
    margin-top: 20px;
}

.course-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 12px 28px rgba(0, 0, 0, 0.08);
    border-color: #CBD5E0;
}

.course-card.popular {
    border: 2px solid #2563EB;
    box-shadow: 0 8px 25px rgba(37, 99, 235, 0.15);
}

.course-header {
    position: relative;
    height: 0;
}

.course-badge {
    position: absolute;
    top: -10px;
    right: 20px;
    background: linear-gradient(135deg, #10B981 0%, #059669 100%);
    color: #FFFFFF;
    padding: 8px 16px;
    border-radius: 20px;
    font-size: 0.75rem;
    font-weight: 600;
    letter-spacing: 0.025em;
    box-shadow: 0 4px 12px rgba(16, 185, 129, 0.3);
    z-index: 10;
    text-transform: uppercase;
    white-space: nowrap;
}

.course-badge.popular {
    background: linear-gradient(135deg, #F59E0B 0%, #D97706 100%);
    box-shadow: 0 3px 10px rgba(245, 158, 11, 0.4);
    animation: pulse 2s infinite;
}

.course-badge.advanced {
    background: linear-gradient(135deg, #8B5CF6 0%, #7C3AED 100%);
    box-shadow: 0 3px 10px rgba(139, 92, 246, 0.3);
}

@keyframes pulse {
    0%, 100% {
        transform: scale(1);
    }
    50% {
        transform: scale(1.05);
    }
}

.course-content {
    padding: 24px 28px 28px 28px;
}

.course-title {
    margin-bottom: 12px;
    font-size: 1.25rem;
    color: #1A202C;
    font-weight: 600;
    line-height: 1.3;
}

.course-description {
    color: #4A5568;
    margin-bottom: 28px;
    line-height: 1.6;
    font-size: 0.95rem;
}

.course-features {
    margin-bottom: 24px;
}

.feature-item {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 10px;
    color: #4A5568;
    font-size: 0.875rem;
}

.feature-item i {
    color: #1E40AF;
    flex-shrink: 0;
    width: 16px;
    text-align: center;
}

.course-price {
    margin-bottom: 28px;
    display: flex;
    align-items: center;
    gap: 12px;
}

.price-original {
    color: #718096;
    text-decoration: line-through;
    font-size: 0.875rem;
    font-weight: 400;
}

.price-current {
    color: #1E40AF;
    font-size: 1.375rem;
    font-weight: 700;
    letter-spacing: -0.025em;
}

/* Testimonials Section */
.testimonials {
    padding: 100px 0;
    background: #FFFFFF;
}

.testimonials-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 32px;
}

.testimonial-card {
    background: #F8FAFC;
    padding: 36px;
    border-radius: 12px;
    border-left: 4px solid #2563EB;
    border: 1px solid #E2E8F0;
    transition: all 0.2s ease;
}

.testimonial-card:hover {
    transform: translateY(-1px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.06);
}

.testimonial-content {
    margin-bottom: 28px;
}

.testimonial-content p {
    font-style: italic;
    color: #2D3748;
    font-size: 1.0rem;
    line-height: 1.7;
    font-weight: 400;
}

.testimonial-author {
    display: flex;
    align-items: center;
    gap: 16px;
}

.author-avatar {
    width: 48px;
    height: 48px;
    background: linear-gradient(135deg, #2563EB 0%, #1D4ED8 100%);
    color: #FFFFFF;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 1.125rem;
}

.author-info h4 {
    font-size: 1rem;
    margin-bottom: 4px;
    color: #1A202C;
    font-weight: 600;
}

.author-info p {
    font-size: 0.875rem;
    color: #4A5568;
    font-weight: 500;
}

/* CTA Section */
.cta {
    padding: 100px 0;
    background: linear-gradient(135deg, #1E40AF 0%, #1E3A8A 100%);
    color: #FFFFFF;
    position: relative;
    overflow: hidden;
}

.cta::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><defs><pattern id="ctaPattern" width="20" height="20" patternUnits="userSpaceOnUse"><circle cx="10" cy="10" r="1" fill="rgba(255,255,255,0.05)"/></pattern></defs><rect width="100" height="100" fill="url(%23ctaPattern)"/></svg>') repeat;
    pointer-events: none;
}

.cta-content {
    text-align: center;
    max-width: 640px;
    margin: 0 auto;
    position: relative;
    z-index: 1;
}

.cta h2 {
    color: #FFFFFF;
    margin-bottom: 20px;
    font-size: 2.25rem;
    font-weight: 600;
    letter-spacing: -0.025em;
}

.cta p {
    color: rgba(255, 255, 255, 0.9);
    font-size: 1.125rem;
    margin-bottom: 40px;
    line-height: 1.7;
}

.cta-buttons {
    display: flex;
    gap: 16px;
    justify-content: center;
}

.cta .btn-primary {
    background: #FFFFFF;
    color: #1E40AF;
    box-shadow: 0 4px 14px rgba(255, 255, 255, 0.25);
}

.cta .btn-primary:hover {
    background: #F8FAFC;
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(255, 255, 255, 0.4);
}

.cta .btn-secondary {
    background: transparent;
    color: #FFFFFF;
    border-color: rgba(255, 255, 255, 0.8);
}

.cta .btn-secondary:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: #FFFFFF;
    transform: translateY(-1px);
}

/* Footer */
.footer {
    background: #1A202C;
    color: #FFFFFF;
    padding: 80px 0 32px;
}

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

.footer-section h3 {
    color: #3B82F6;
    margin-bottom: 20px;
    font-size: 1.375rem;
    font-weight: 600;
}

.footer-section h4 {
    color: #FFFFFF;
    margin-bottom: 20px;
    font-weight: 600;
    font-size: 1.0rem;
}

.footer-section p {
    color: #A0AEC0;
    line-height: 1.7;
    font-size: 0.95rem;
}

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

.footer-section ul li {
    margin-bottom: 8px;
}

.footer-section ul li a {
    color: #A0AEC0;
    text-decoration: none;
    transition: color 0.2s ease;
    font-size: 0.95rem;
}

.footer-section ul li a:hover {
    color: #3B82F6;
}

.footer-bottom {
    border-top: 1px solid #2D3748;
    padding-top: 32px;
    text-align: center;
}

.footer-bottom p {
    color: #A0AEC0;
    font-size: 0.9rem;
}

/* Responsive Design */
@media (max-width: 1024px) {
    .hero-container {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 48px;
    }
    
    .hero-title {
        font-size: 3rem;
    }
    
    .features-grid {
        grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
        gap: 24px;
    }
    
    .courses-grid {
        grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    }
}

@media (max-width: 768px) {
    .nav-menu {
        display: none;
    }
    
    .nav-toggle {
        display: flex;
    }
    
    .hero {
        padding: 100px 0 60px;
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .hero-subtitle {
        font-size: 1.125rem;
    }
    
    .hero-buttons {
        flex-direction: column;
        align-items: center;
        gap: 12px;
    }
    
    .hero-buttons .btn-primary,
    .hero-buttons .btn-secondary {
        width: 100%;
        max-width: 300px;
    }
    
    .hero-stats {
        justify-content: center;
        gap: 32px;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .courses-grid {
        grid-template-columns: 1fr;
    }
    
    .testimonials-grid {
        grid-template-columns: 1fr;
    }
    
    .cta h2 {
        font-size: 2rem;
    }
    
    .cta-buttons {
        flex-direction: column;
        align-items: center;
    }
    
    .cta-buttons .btn-primary,
    .cta-buttons .btn-secondary {
        width: 100%;
        max-width: 300px;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        gap: 32px;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 12px;
    }
    
    .hero-container {
        padding: 0 12px;
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .hero-subtitle {
        font-size: 1rem;
    }
    
    .section-title {
        font-size: 1.75rem;
    }
    
    .feature-card,
    .testimonial-card {
        padding: 24px;
    }
    
    .course-content {
        padding: 20px;
    }
    
    .cta h2 {
        font-size: 1.75rem;
    }
    
    .cta p {
        font-size: 1.125rem;
    }
}

/* Smooth Scrolling */
html {
    scroll-behavior: smooth;
}

/* Animation Classes */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.fade-in-up {
    animation: fadeInUp 0.6s ease-out;
}

/* Focus States for Accessibility */
.btn-primary:focus,
.btn-secondary:focus,
.nav-link:focus {
    outline: 2px solid #7C3AED;
    outline-offset: 2px;
}

/* Loading States */
.loading {
    opacity: 0.7;
    pointer-events: none;
}

/* Touch Improvements for Mobile */
@media (hover: none) and (pointer: coarse) {
    .btn-primary:hover,
    .btn-secondary:hover,
    .feature-card:hover,
    .course-card:hover {
        transform: none;
    }
    
    .btn-primary:active {
        transform: scale(0.95);
    }
    
    .btn-secondary:active {
        transform: scale(0.95);
    }
}