:root {
    --primary: #0056b3;
    --secondary: #f8a31c;
    --accent: #2d3748;
}

.gradient-bg {
    background: linear-gradient(135deg, #1e3c72 0%, #2a5298 100%);
}

.btn-primary {
    background-color: var(--primary);
    color: white;
    padding: 12px 28px;
    border-radius: 4px;
    font-weight: 600;
    transition: all 0.3s ease;
    display: inline-block;
    text-align: center;
}

.btn-primary:hover {
    background-color: #004494;
    transform: translateY(-2px);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.1);
}

.btn-secondary {
    background-color: var(--secondary);
    color: #333;
    padding: 12px 28px;
    border-radius: 4px;
    font-weight: 600;
    transition: all 0.3s ease;
    display: inline-block;
    text-align: center;
}

.btn-secondary:hover {
    background-color: #e69500;
    transform: translateY(-2px);
}

.section-padding {
    padding: 80px 0;
}

.hero-section {
    background: linear-gradient(rgba(0, 0, 0, 0.7), rgba(0, 0, 0, 0.7)), url('https://images.unsplash.com/photo-1581094794329-c8112a89af12?ixlib=rb-4.0.3&auto=format&fit=crop&w=1920&q=80');
    background-size: cover;
    background-position: center;
    background-attachment: fixed;
}

.sticky-nav {
    position: sticky;
    top: 0;
    z-index: 1000;
    transition: all 0.3s ease;
}

.sticky-nav.scrolled {
    background-color: rgba(255, 255, 255, 0.95);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
}

.product-card {
    transition: all 0.3s ease;
    border-radius: 8px;
    overflow: hidden;
}

.product-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
}

.contact-form input, .contact-form textarea, .contact-form select {
    width: 100%;
    padding: 12px 15px;
    border: 1px solid #ddd;
    border-radius: 4px;
    margin-bottom: 20px;
    transition: all 0.3s ease;
    font-family: inherit;
    font-size: 16px;
}

.contact-form input:focus, .contact-form textarea:focus, .contact-form select:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(0, 86, 179, 0.1);
    outline: none;
}

.contact-form label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
}

/* 响应式调整 */
@media (max-width: 768px) {
    .section-padding {
        padding: 60px 0;
    }
    
    .hero-section {
        background-attachment: scroll;
    }
}