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

body {
    font-family: 'Microsoft YaHei', 'PingFang SC', 'Helvetica Neue', Arial, sans-serif;
    background: linear-gradient(180deg, #f8f9fa 0%, #e9ecef 100%);
    min-height: 100vh;
    color: #333;
    line-height: 1.6;
}

.header {
    background: linear-gradient(135deg, #1a4a8d 0%, #2c5aa0 50%, #1a4a8d 100%);
    color: white;
    padding: 30px 20px;
    text-align: center;
    box-shadow: 0 4px 20px rgba(26, 74, 141, 0.3);
}

.header-content {
    max-width: 1200px;
    margin: 0 auto;
}

.logo-section {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 20px;
    margin-bottom: 10px;
}

.logo {
    height: 60px;
    width: auto;
}

.site-title {
    font-size: 2.2em;
    font-weight: bold;
    letter-spacing: 4px;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.2);
}

.site-subtitle {
    font-size: 0.9em;
    letter-spacing: 2px;
    opacity: 0.9;
    margin-top: 5px;
}

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

.section-title {
    font-size: 1.6em;
    color: #1a4a8d;
    text-align: center;
    margin-bottom: 30px;
    position: relative;
    padding-bottom: 15px;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 3px;
    background: linear-gradient(90deg, #1a4a8d, #4a90d9);
    border-radius: 2px;
}

.product-section {
    background: white;
    border-radius: 12px;
    padding: 40px;
    margin-bottom: 40px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
}

.product-container {
    display: flex;
    gap: 40px;
    align-items: flex-start;
}

.product-image {
    flex: 0 0 400px;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
    border: 1px solid #e9ecef;
}

.product-image img {
    width: 100%;
    height: auto;
    display: block;
    transition: transform 0.3s ease;
}

.product-image:hover img {
    transform: scale(1.02);
}

.product-info {
    flex: 1;
}

.product-name {
    font-size: 1.8em;
    color: #1a4a8d;
    margin-bottom: 20px;
    padding-bottom: 15px;
    border-bottom: 2px solid #e9ecef;
}

.product-details {
    background: #f8f9fa;
    padding: 20px;
    border-radius: 8px;
    margin-bottom: 25px;
}

.product-details p {
    margin-bottom: 12px;
    font-size: 1em;
}

.product-details p:last-child {
    margin-bottom: 0;
}

.product-details strong {
    color: #1a4a8d;
    min-width: 100px;
    display: inline-block;
}

.product-description h4 {
    font-size: 1.1em;
    color: #1a4a8d;
    margin-bottom: 12px;
}

.product-description p {
    color: #666;
    line-height: 1.8;
    text-align: justify;
}

.documents-section {
    background: white;
    border-radius: 12px;
    padding: 40px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
}

.documents-container {
    display: flex;
    justify-content: center;
    gap: 30px;
    flex-wrap: wrap;
}

.document-item {
    flex: 0 0 280px;
    background: linear-gradient(135deg, #f8f9fa 0%, #ffffff 100%);
    border: 1px solid #e9ecef;
    border-radius: 12px;
    padding: 30px;
    text-align: center;
    transition: all 0.3s ease;
}

.document-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 30px rgba(26, 74, 141, 0.15);
    border-color: #4a90d9;
}

.document-icon {
    width: 60px;
    height: 60px;
    margin: 0 auto 20px;
    background: linear-gradient(135deg, #1a4a8d 0%, #4a90d9 100%);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
}

.document-icon svg {
    width: 30px;
    height: 30px;
    stroke: white;
}

.document-item h3 {
    font-size: 1.3em;
    color: #1a4a8d;
    margin-bottom: 10px;
}

.document-item p {
    color: #666;
    font-size: 0.9em;
    margin-bottom: 20px;
}

.btn-document {
    background: linear-gradient(135deg, #1a4a8d 0%, #2c5aa0 100%);
    color: white;
    border: none;
    padding: 12px 30px;
    border-radius: 25px;
    font-size: 1em;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(26, 74, 141, 0.3);
}

.btn-document:hover {
    background: linear-gradient(135deg, #2c5aa0 0%, #4a90d9 100%);
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(26, 74, 141, 0.4);
}

.btn-document:active {
    transform: translateY(0);
}

.footer {
    background: #1a4a8d;
    color: white;
    padding: 40px 20px 20px;
    margin-top: 40px;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    text-align: center;
}

.contact-info {
    margin-bottom: 20px;
}

.contact-info h4 {
    font-size: 1.1em;
    margin-bottom: 15px;
    color: #fff;
}

.contact-info p {
    font-size: 0.9em;
    margin-bottom: 8px;
    opacity: 0.9;
}

.copyright {
    padding-top: 20px;
    border-top: 1px solid rgba(255, 255, 255, 0.2);
}

.copyright p {
    font-size: 0.85em;
    opacity: 0.8;
}

@media (max-width: 900px) {
    .product-container {
        flex-direction: column;
        align-items: center;
    }

    .product-image {
        flex: none;
        width: 100%;
        max-width: 400px;
    }

    .product-info {
        width: 100%;
    }

    .site-title {
        font-size: 1.6em;
        letter-spacing: 2px;
    }

    .documents-container {
        flex-direction: column;
        align-items: center;
    }

    .document-item {
        width: 100%;
        max-width: 300px;
    }
}

@media (max-width: 500px) {
    .header {
        padding: 20px 15px;
    }

    .site-title {
        font-size: 1.3em;
    }

    .site-subtitle {
        font-size: 0.75em;
    }

    .product-section,
    .documents-section {
        padding: 25px 20px;
    }

    .section-title {
        font-size: 1.3em;
    }

    .product-name {
        font-size: 1.4em;
    }

    .document-item {
        padding: 25px 20px;
    }
}