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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.6;
    color: #333;
}

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

/* Header */
header {
    background: #fff;
    box-shadow: 0 2px 10px rgba(0,0,0,0.08);
    position: sticky;
    top: 0;
    z-index: 100;
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 20px;
    max-width: 1200px;
    margin: 0 auto;
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 24px;
    font-weight: 600;
    color: #1d4ed8;
}

.logo-icon {
    width: 2rem;
    height: 2rem;
    border-radius: 0.5rem;
}

.nav-links {
    display: flex;
    gap: 30px;
}

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

.nav-links a:hover {
    color: #1d4ed8;
}

/* Hero */
.hero {
    background: linear-gradient(135deg, #f8fafc 0%, #e2e8f0 100%);
    padding: 80px 0;
    text-align: center;
}

.app-icon-large {
    margin-bottom: 30px;
}

.app-icon-large img {
    width: 7.5rem;
    height: 7.5rem;
    border-radius: 1.5rem;
    box-shadow: 0 0.5rem 1.875rem rgba(0,0,0,0.12);
}

.hero h1 {
    font-size: 3.5rem;
    margin-bottom: 10px;
    font-weight: 700;
    color: #1e293b;
}

.app-subtitle {
    font-size: 1.4rem;
    color: #64748b;
    margin-bottom: 20px;
    font-weight: 500;
}

.hero-description {
    font-size: 1.1rem;
    margin-bottom: 40px;
    color: #475569;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.btn-primary {
    display: inline-block;
    padding: 15px 30px;
    background: #1d4ed8;
    color: #fff;
    text-decoration: none;
    border-radius: 8px;
    font-weight: 600;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(29, 78, 216, 0.3);
}

.btn-primary:hover {
    background: #1e40af;
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(29, 78, 216, 0.4);
}

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

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

.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 40px;
    margin-top: 60px;
}

.feature {
    background: white;
    padding: 40px;
    border-radius: 16px;
    text-align: center;
    box-shadow: 0 4px 20px rgba(0,0,0,0.08);
    transition: transform 0.3s ease;
    border: 1px solid #f1f5f9;
}

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

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

.feature h3 {
    font-size: 1.4rem;
    margin-bottom: 15px;
    color: #1e293b;
    font-weight: 600;
}

.feature p {
    color: #64748b;
    line-height: 1.7;
}

/* App Description */
.app-description {
    padding: 100px 0;
    background: #f8fafc;
}

.app-description h2 {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 40px;
    color: #1e293b;
}

.app-description > .container > p {
    font-size: 1.2rem;
    text-align: center;
    color: #64748b;
    max-width: 800px;
    margin: 0 auto 60px;
    line-height: 1.7;
}

.functionality {
    background: #ffffff;
    padding: 60px;
    border-radius: 16px;
    max-width: 900px;
    margin: 0 auto 60px;
    box-shadow: 0 4px 20px rgba(0,0,0,0.08);
}

.functionality h3 {
    font-size: 1.8rem;
    margin-bottom: 30px;
    color: #1e293b;
    text-align: center;
}

.features-list {
    display: grid;
    gap: 20px;
}

.feature-item {
    padding: 20px;
    background: #f8fafc;
    border-radius: 12px;
    border-left: 4px solid #1d4ed8;
    color: #4b5563;
    line-height: 1.6;
}

.feature-item strong {
    color: #1d4ed8;
}

.tech-details {
    background: #ffffff;
    padding: 40px;
    border-radius: 16px;
    max-width: 900px;
    margin: 0 auto;
    text-align: center;
    box-shadow: 0 4px 20px rgba(0,0,0,0.08);
}

.tech-details h3 {
    font-size: 1.6rem;
    margin-bottom: 20px;
    color: #1e293b;
}

.tech-details p {
    color: #64748b;
    line-height: 1.7;
}

/* Footer */
footer {
    background: #1e293b;
    color: white;
    padding: 60px 0 30px;
}

.footer-links {
    display: flex;
    justify-content: center;
    gap: 40px;
    margin-bottom: 30px;
}

.footer-links a {
    color: #94a3b8;
    text-decoration: none;
    transition: color 0.3s;
}

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

footer p {
    text-align: center;
    color: #64748b;
    margin-top: 20px;
}

/* Responsive */
@media (max-width: 768px) {
    .hero h1 {
        font-size: 2.5rem;
    }
    
    .app-icon-large img {
        width: 5rem;
        height: 5rem;
        border-radius: 1rem;
    }
    
    .nav-links {
        gap: 20px;
    }
    
    .functionality {
        padding: 40px 30px;
    }
    
    .footer-links {
        flex-direction: column;
        gap: 20px;
        text-align: center;
    }
    
    .feature-grid {
        grid-template-columns: 1fr;
    }
}