* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f8f9fa;
}

header {
    background: linear-gradient(135deg, #2c3e50 0%, #34495e 100%);
    padding: 1rem 0;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

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

nav .logo {
    color: white;
    font-size: 1.8rem;
    font-weight: 700;
    text-decoration: none;
    display: inline-block;
}

nav ul {
    list-style: none;
    float: right;
    margin-top: 8px;
}

nav ul li {
    display: inline-block;
    margin-left: 30px;
}

nav ul li a {
    color: white;
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s;
}

nav ul li a:hover {
    color: #3498db;
}

.banner {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 60px 20px;
    text-align: center;
}

.banner h1 {
    font-size: 3rem;
    margin-bottom: 10px;
}

.banner p {
    font-size: 1.2rem;
    opacity: 0.9;
}

.container {
    max-width: 1200px;
    margin: 40px auto;
    padding: 0 20px;
}

.section-title {
    text-align: center;
    margin-bottom: 40px;
}

.section-title h2 {
    font-size: 2.2rem;
    color: #2c3e50;
    margin-bottom: 10px;
}

.section-title p {
    color: #7f8c8d;
}

.product-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
}

.product-card {
    background: white;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
    transition: transform 0.3s, box-shadow 0.3s;
    text-decoration: none;
    color: #333;
}

.product-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 25px rgba(0,0,0,0.15);
}

.product-card img {
    width: 100%;
    height: 200px;
    object-fit: cover;
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
}

.product-card .product-info {
    padding: 20px;
}

.product-card h3 {
    font-size: 1.2rem;
    margin-bottom: 10px;
    color: #2c3e50;
}

.product-card p {
    color: #7f8c8d;
    font-size: 0.9rem;
    margin-bottom: 15px;
}

.product-card .price {
    font-size: 1.5rem;
    font-weight: 700;
    color: #e74c3c;
}

.product-card .category {
    display: inline-block;
    background: #3498db;
    color: white;
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 0.8rem;
    margin-bottom: 10px;
}

footer {
    background: #2c3e50;
    color: white;
    padding: 40px 20px;
    margin-top: 60px;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
}

.footer-section h3 {
    margin-bottom: 20px;
    color: #3498db;
}

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

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

.footer-section ul li a {
    color: #bdc3c7;
    text-decoration: none;
    transition: color 0.3s;
}

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

.footer-bottom {
    text-align: center;
    margin-top: 30px;
    padding-top: 20px;
    border-top: 1px solid #34495e;
    color: #95a5a6;
}

.product-detail {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
    background: white;
    padding: 40px;
    border-radius: 12px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
}

.product-detail img {
    width: 100%;
    height: 400px;
    object-fit: cover;
    border-radius: 8px;
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
}

.product-detail h2 {
    font-size: 2rem;
    margin-bottom: 20px;
    color: #2c3e50;
}

.product-detail .price {
    font-size: 2.5rem;
    font-weight: 700;
    color: #e74c3c;
    margin-bottom: 20px;
}

.product-detail .description {
    margin-bottom: 20px;
    color: #7f8c8d;
}

.product-detail .features {
    margin-bottom: 30px;
}

.product-detail .features h4 {
    margin-bottom: 15px;
    color: #2c3e50;
}

.product-detail .features ul {
    list-style: none;
}

.product-detail .features li {
    padding: 8px 0;
    border-bottom: 1px solid #eee;
    position: relative;
    padding-left: 20px;
}

.product-detail .features li:before {
    content: '✓';
    position: absolute;
    left: 0;
    color: #27ae60;
    font-weight: bold;
}

.btn {
    display: inline-block;
    padding: 12px 30px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    text-decoration: none;
    border-radius: 6px;
    font-weight: 500;
    transition: transform 0.3s, box-shadow 0.3s;
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
}

.back-link {
    display: inline-block;
    margin-bottom: 20px;
    color: #3498db;
    text-decoration: none;
    font-weight: 500;
}

.back-link:hover {
    text-decoration: underline;
}

@media (max-width: 768px) {
    nav ul {
        float: none;
        text-align: center;
        margin-top: 15px;
    }
    
    nav ul li {
        margin-left: 15px;
        margin-right: 15px;
    }
    
    .banner h1 {
        font-size: 2rem;
    }
    
    .product-grid {
        grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
        gap: 20px;
    }
    
    .product-detail {
        grid-template-columns: 1fr;
    }
    
    .product-detail img {
        height: 300px;
    }
}