/* Reset and base styles */
* {
    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;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 12px 24px;
    border: none;
    border-radius: 8px;
    font-size: 14px;
    font-weight: 500;
    text-decoration: none;
    cursor: pointer;
    transition: all 0.3s ease;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.btn-primary:hover {
    opacity: 0.9;
    transform: translateY(-1px);
}

.btn-outline {
    background: transparent;
    border: 2px solid #667eea;
    color: #667eea;
}

.btn-outline:hover {
    background: #667eea;
    color: white;
}

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

.btn-full {
    width: 100%;
}

/* Header */
.header {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(0, 0, 0, 0.1);
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
}

.nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 0;
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: 12px;
}

.logo {
    width: 40px;
    height: 40px;
    border-radius: 8px;
    object-fit: cover;
}

.brand-text {
    font-size: 24px;
    font-weight: bold;
    color: #333;
}

.nav-links {
    display: flex;
    gap: 32px;
}

.nav-links a {
    text-decoration: none;
    color: #666;
    font-weight: 500;
    transition: color 0.3s ease;
}

.nav-links a:hover {
    color: #667eea;
}

/* Hero Section */
.hero {
    position: relative;
    padding: 120px 0 80px;
    text-align: center;
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    opacity: 0.05;
}

.hero-content {
    position: relative;
    z-index: 10;
}

.badge {
    display: inline-block;
    background: rgba(102, 126, 234, 0.1);
    color: #667eea;
    padding: 8px 16px;
    border-radius: 20px;
    font-size: 14px;
    font-weight: 500;
    margin-bottom: 24px;
}

.hero-title {
    font-size: 48px;
    font-weight: bold;
    margin-bottom: 24px;
    line-height: 1.2;
}

.gradient-text {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-description {
    font-size: 20px;
    color: #666;
    margin-bottom: 32px;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

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

.hero-features {
    display: flex;
    gap: 24px;
    justify-content: center;
    flex-wrap: wrap;
}

.feature-item {
    display: flex;
    align-items: center;
    gap: 8px;
    color: #666;
    font-size: 14px;
}

.feature-dot {
    width: 8px;
    height: 8px;
    background: #22c55e;
    border-radius: 50%;
}

/* Features Section */
.features {
    padding: 80px 0;
    background: rgba(248, 250, 252, 0.5);
}

.section-header {
    text-align: center;
    margin-bottom: 64px;
}

.section-header h2 {
    font-size: 36px;
    font-weight: bold;
    margin-bottom: 16px;
    color: #333;
}

.section-header p {
    font-size: 18px;
    color: #666;
    max-width: 600px;
    margin: 0 auto;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 24px;
}

.feature-card {
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.8) 0%, rgba(248, 250, 252, 0.8) 100%);
    border: 1px solid rgba(0, 0, 0, 0.05);
    border-radius: 16px;
    padding: 32px 24px;
    text-align: center;
    transition: all 0.3s ease;
}

.feature-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
}

.feature-icon {
    font-size: 48px;
    margin-bottom: 16px;
}

.feature-card h3 {
    font-size: 20px;
    font-weight: bold;
    margin-bottom: 12px;
    color: #333;
}

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

/* Pricing Section */
.pricing {
    padding: 80px 0;
}

.pricing-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 32px;
    max-width: 1000px;
    margin: 0 auto;
}

.pricing-card {
    background: white;
    border: 1px solid rgba(0, 0, 0, 0.1);
    border-radius: 16px;
    overflow: hidden;
    position: relative;
    transition: all 0.3s ease;
}

.pricing-card:hover {
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
}

.pricing-card.popular {
    border: 2px solid #667eea;
    transform: scale(1.05);
    box-shadow: 0 20px 40px rgba(102, 126, 234, 0.2);
}

.popular-badge {
    position: absolute;
    top: -12px;
    left: 50%;
    transform: translateX(-50%);
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 6px 20px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 600;
    margin-top: 20px;
}

.pricing-header {
    padding: 32px 24px;
    text-align: center;
    border-bottom: 1px solid rgba(0, 0, 0, 0.1);
}

.pricing-header h3 {
    font-size: 24px;
    font-weight: bold;
    margin-bottom: 16px;
    color: #333;
}

.price {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 4px;
    margin-bottom: 8px;
}

.price-main {
    font-size: 32px;
    font-weight: bold;
    color: #333;
}

.price-period {
    color: #666;
    font-size: 16px;
}

.price-old {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
}

.original-price {
    text-decoration: line-through;
    color: #999;
    font-size: 14px;
}

.discount {
    background: #ef4444;
    color: white;
    padding: 2px 8px;
    border-radius: 4px;
    font-size: 12px;
    font-weight: 600;
}

.pricing-features {
    padding: 24px;
}

.feature-list {
    margin-bottom: 24px;
}

.feature-item-pricing {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 12px;
}

.check-icon {
    width: 20px;
    height: 20px;
    background: #22c55e;
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 12px;
    font-weight: bold;
    flex-shrink: 0;
}

.cross-icon {
    width: 20px;
    height: 20px;
    background: #e5e7eb;
    color: #9ca3af;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 12px;
    font-weight: bold;
    flex-shrink: 0;
}

.limitation {
    opacity: 0.6;
}

.limitation span {
    color: #666;
}

.pricing-note {
    text-align: center;
    margin-top: 48px;
    color: #666;
}

/* Comparison Section */
.comparison {
    padding: 80px 0;
    background: rgba(248, 250, 252, 0.5);
}

.comparison-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: 32px;
    max-width: 1000px;
    margin: 0 auto;
}

.comparison-card {
    background: white;
    border-radius: 16px;
    overflow: hidden;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
}

.comparison-card.matbot {
    border: 2px solid #667eea;
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.05) 0%, rgba(255, 255, 255, 1) 100%);
}

.comparison-header {
    padding: 24px;
    text-align: center;
    border-bottom: 1px solid rgba(0, 0, 0, 0.1);
}

.comparison-header h3 {
    font-size: 24px;
    font-weight: bold;
}

.tutor .comparison-header h3 {
    color: #ef4444;
}

.matbot .comparison-header h3 {
    color: #667eea;
}

.comparison-content {
    padding: 24px;
}

.comparison-items {
    margin-bottom: 24px;
}

.comparison-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px 0;
    border-bottom: 1px solid rgba(0, 0, 0, 0.1);
}

.comparison-item:last-child {
    border-bottom: none;
}

.value {
    font-weight: 600;
}

.total {
    font-size: 20px;
    font-weight: bold;
}

.expensive {
    color: #ef4444;
}

.affordable {
    color: #22c55e;
}

.limitations,
.advantages {
    margin-top: 24px;
}

.limitations h4,
.advantages h4 {
    font-weight: 600;
    margin-bottom: 12px;
}

.advantages h4 {
    color: #22c55e;
}

.limitations ul,
.advantages ul {
    list-style: none;
    padding: 0;
}

.limitations li,
.advantages li {
    color: #666;
    font-size: 14px;
    margin-bottom: 8px;
}

.savings-highlight {
    background: linear-gradient(135deg, rgba(34, 197, 94, 0.1) 0%, rgba(34, 197, 94, 0.05) 100%);
    border-radius: 16px;
    padding: 32px;
    text-align: center;
    margin-top: 48px;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.savings-highlight h3 {
    font-size: 28px;
    font-weight: bold;
    color: #22c55e;
    margin-bottom: 12px;
}

.savings-highlight p {
    color: #666;
    font-size: 16px;
}

/* Footer */
.footer {
    background: #1f2937;
    color: white;
    padding: 48px 0 24px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 32px;
    margin-bottom: 32px;
}

.footer-brand {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 16px;
}

.footer-logo {
    width: 32px;
    height: 32px;
    border-radius: 6px;
    object-fit: cover;
}

.footer-brand-text {
    font-size: 18px;
    font-weight: bold;
}

.footer-section h4 {
    font-weight: 600;
    margin-bottom: 16px;
}

.footer-section ul {
    list-style: none;
    padding: 0;
}

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

.footer-section a {
    color: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    font-size: 14px;
    transition: color 0.3s ease;
}

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

.footer-section p {
    color: rgba(255, 255, 255, 0.7);
    font-size: 14px;
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.2);
    padding-top: 24px;
    text-align: center;
}

.footer-bottom p {
    color: rgba(255, 255, 255, 0.7);
    font-size: 14px;
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-links {
        display: none;
    }
    
    .hero-title {
        font-size: 36px;
    }
    
    .hero-description {
        font-size: 18px;
    }
    
    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }
    
    .hero-features {
        flex-direction: column;
        align-items: center;
    }
    
    .section-header h2 {
        font-size: 28px;
    }
    
    .pricing-grid {
        grid-template-columns: 1fr;
    }
    
    .comparison-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
}