/* Reset and base styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', system-ui, sans-serif;
    line-height: 1.6;
    color: #1a1a1a;
    overflow-x: hidden;
}

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

/* Navigation */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    z-index: 1000;
    border-bottom: 1px solid rgba(0, 0, 0, 0.1);
    height: 80px;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 20px;
    height: 100%;
}

.logo {
    display: flex;
    align-items: center;
    gap: 8px;
    font-weight: 700;
    font-size: 1.5rem;
}

.logo-icon {
    width: 40px;
    height: 40px;
    object-fit: contain;
}

.logo-text {
    color: #1a1a1a;
    font-weight: 800;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 2rem;
}

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

.nav-links a:hover {
    color: #1a1a1a;
}

.download-btn {
    background: #1a1a1a;
    color: white !important;
    padding: 0.5rem 1rem;
    border-radius: 8px;
    font-weight: 600;
    transition: all 0.3s ease;
}

.download-btn:hover {
    transform: translateY(-2px);
    background: #333;
}

/* Hero Section */
.hero {
    padding: 140px 0 80px;
    background: #fafafa;
    min-height: 100vh;
    display: flex;
    align-items: center;
}

.hero-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 800;
    line-height: 1.1;
    margin-bottom: 1.5rem;
    color: #1a1a1a;
}

.highlight {
    color: #1a1a1a;
    font-weight: 900;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: #666;
    margin-bottom: 2rem;
    line-height: 1.6;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    margin-bottom: 2rem;
}

.btn {
    display: inline-block;
    padding: 1rem 2rem;
    border-radius: 12px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    border: none;
    cursor: pointer;
    font-size: 1rem;
}

.btn.primary {
    background: #1a1a1a;
    color: white;
}

.btn.primary:hover {
    transform: translateY(-3px);
    background: #333;
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.2);
}

.btn.secondary {
    background: white;
    color: #333;
    border: 2px solid #f0f0f0;
}

.btn.secondary:hover {
    border-color: #1a1a1a;
    color: #1a1a1a;
}

.btn.large {
    padding: 1.25rem 2.5rem;
    font-size: 1.1rem;
}

.trust-indicators {
    display: flex;
    gap: 2rem;
    margin-top: 1rem;
}

.trust-item {
    color: #666;
    font-size: 0.9rem;
    font-weight: 500;
}

/* Browser Mockup */
.browser-mockup {
    background: white;
    border-radius: 12px;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
    overflow: hidden;
    transform: perspective(1000px) rotateY(-5deg) rotateX(5deg);
    transition: transform 0.3s ease;
}

.browser-mockup:hover {
    transform: perspective(1000px) rotateY(0deg) rotateX(0deg);
}

.browser-header {
    background: #f8f9fa;
    padding: 1rem;
    border-bottom: 1px solid #f0f0f0;
}

.browser-dots {
    display: flex;
    gap: 0.5rem;
}

.browser-dots span {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: #ddd;
}

.browser-dots span:nth-child(1) { background: #ff5f57; }
.browser-dots span:nth-child(2) { background: #ffbd2e; }
.browser-dots span:nth-child(3) { background: #28ca42; }

.browser-content {
    padding: 2rem;
}

.quiz-demo .question {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: #1a1a1a;
}

.options {
    margin-bottom: 1.5rem;
}

.option {
    padding: 0.75rem 1rem;
    margin: 0.5rem 0;
    border: 2px solid #f0f0f0;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
}

.option.correct {
    border-color: #1a1a1a;
    background: rgba(26, 26, 26, 0.05);
    color: #1a1a1a;
    font-weight: 600;
}

.ai-explanation {
    background: rgba(26, 26, 26, 0.05);
    border-left: 3px solid #1a1a1a;
    padding: 1rem;
    border-radius: 8px;
    color: #333;
    font-size: 0.9rem;
    font-style: italic;
}

/* Features Section */
.features {
    padding: 100px 0 80px;
    background: #fafafa;
    scroll-margin-top: 100px;
}

.section-title {
    text-align: center;
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 3rem;
    color: #1a1a1a;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
}

.feature-card {
    padding: 2rem;
    border-radius: 16px;
    background: white;
    border: 1px solid #f0f0f0;
    transition: all 0.3s ease;
    text-align: center;
}

.feature-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.1);
    border-color: #1a1a1a;
}

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

.feature-card h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: #1a1a1a;
}

.feature-card p {
    color: #666;
    line-height: 1.6;
}

/* How It Works Section */
.how-it-works {
    padding: 100px 0 80px;
    background: white;
    scroll-margin-top: 100px;
}

.steps {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 3rem;
    margin-top: 3rem;
}

.step {
    text-align: center;
    position: relative;
}

.step-number {
    width: 60px;
    height: 60px;
    border-radius: 50%;
    background: #1a1a1a;
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    font-weight: 700;
    margin: 0 auto 1.5rem;
}

.step h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: #1a1a1a;
}

.step p {
    color: #666;
    line-height: 1.6;
}

/* CTA Section */
.cta {
    padding: 100px 0 80px;
    background: #1a1a1a;
    color: white;
    text-align: center;
    scroll-margin-top: 100px;
}

.cta h2 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
}

.cta p {
    font-size: 1.1rem;
    margin-bottom: 2rem;
    opacity: 0.9;
}

.cta .btn.primary {
    background: white;
    color: #1a1a1a;
}

.cta .btn.primary:hover {
    transform: translateY(-3px);
    background: #f0f0f0;
    box-shadow: 0 10px 25px rgba(255, 255, 255, 0.3);
}

.cta-note {
    margin-top: 1rem;
    font-size: 0.9rem;
    opacity: 0.8;
}

/* Footer */
.footer {
    background: #1a1a1a;
    color: white;
    padding: 60px 0 30px;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 2rem;
}

.footer-left p {
    color: #999;
    margin-top: 0.5rem;
}

.footer-links {
    display: flex;
    gap: 2rem;
}

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

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

.footer-bottom {
    border-top: 1px solid #333;
    padding-top: 2rem;
    text-align: center;
    color: #999;
}

/* Responsive Design */
@media (max-width: 768px) {
    .hero {
        padding: 120px 0 60px;
    }
    
    .hero-container {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 2rem;
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }
    
    .trust-indicators {
        flex-direction: column;
        align-items: center;
        gap: 1rem;
    }
    
    .nav-links {
        display: none;
    }
    
    .features {
        padding: 80px 0 60px;
    }
    
    .how-it-works {
        padding: 80px 0 60px;
    }
    
    .cta {
        padding: 80px 0 60px;
    }
    
    .footer-content {
        flex-direction: column;
        gap: 2rem;
    }
    
    .footer-links {
        flex-direction: column;
        gap: 1rem;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .steps {
        grid-template-columns: 1fr;
    }
}

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

/* Animation for page load */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.hero-content {
    animation: fadeInUp 0.8s ease-out;
}

/* Intersection observer animations handled in JS */
.feature-card,
.step {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.feature-card.animate,
.step.animate {
    opacity: 1;
    transform: translateY(0);
}