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

:root {
    --primary: #003399;
    --secondary: #3366CC;
    --accent: #FFCC00;
    --white: #FFFFFF;
    --gray: #CCCCCC;
    --dark: #000000;
    --text: #333333;
    --text-light: #666666;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: "Microsoft YaHei", "PingFang SC", "Hiragino Sans GB", Arial, sans-serif;
    color: var(--text);
    line-height: 1.6;
    background: var(--white);
}

a {
    text-decoration: none;
    color: inherit;
    transition: all 0.3s ease;
}

ul {
    list-style: none;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

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

.btn {
    display: inline-block;
    padding: 12px 32px;
    background: var(--primary);
    color: var(--white);
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    transition: all 0.3s ease;
}

.btn:hover {
    background: var(--secondary);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 51, 153, 0.3);
}

.btn-accent {
    background: var(--accent);
    color: var(--dark);
}

.btn-accent:hover {
    background: #e6b800;
    box-shadow: 0 4px 12px rgba(255, 204, 0, 0.3);
}

.section {
    padding: 80px 0;
}

.section-title {
    text-align: center;
    margin-bottom: 50px;
}

.section-title h2 {
    font-size: 32px;
    color: var(--primary);
    margin-bottom: 12px;
    font-weight: 600;
}

.section-title p {
    color: var(--text-light);
    font-size: 15px;
}

.section-title .line {
    width: 60px;
    height: 3px;
    background: var(--accent);
    margin: 16px auto 0;
}

.top-bar {
    background: var(--primary);
    color: var(--white);
    font-size: 13px;
    padding: 8px 0;
}

.top-bar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 10px;
}

.top-bar .contact-info span {
    margin-right: 24px;
}

.top-bar .contact-info i {
    color: var(--accent);
    margin-right: 6px;
}

.header {
    background: var(--white);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 18px 20px;
}

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

.logo-text {
    font-size: 22px;
    font-weight: 700;
    color: var(--primary);
}

.logo-text small {
    display: block;
    font-size: 12px;
    color: var(--text-light);
    font-weight: 400;
    letter-spacing: 1px;
}

.nav {
    display: flex;
    align-items: center;
}

.nav ul {
    display: flex;
    gap: 4px;
}

.nav a {
    display: block;
    padding: 10px 20px;
    color: var(--text);
    font-size: 15px;
    font-weight: 500;
    border-radius: 4px;
}

.nav a:hover,
.nav a.active {
    background: var(--primary);
    color: var(--white);
}

.nav .menu-toggle {
    display: none;
    font-size: 24px;
    background: none;
    border: none;
    color: var(--primary);
    cursor: pointer;
}

.hero {
    position: relative;
    height: 560px;
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    color: var(--white);
    overflow: hidden;
}

.hero-slide {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
    transition: opacity 1s ease;
    background-size: cover;
    background-position: center;
}

.hero-slide.active {
    opacity: 1;
}

.hero-slide::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, rgba(0, 51, 153, 0.85) 0%, rgba(51, 102, 204, 0.75) 100%);
}

.hero-content {
    position: relative;
    z-index: 2;
    height: 100%;
    display: flex;
    flex-direction: column;
    justify-content: center;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.hero-content h1 {
    font-size: 44px;
    font-weight: 700;
    margin-bottom: 20px;
    line-height: 1.3;
}

.hero-content p {
    font-size: 18px;
    margin-bottom: 32px;
    opacity: 0.95;
    max-width: 640px;
}

.hero-buttons {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
}

.features {
    background: #f5f7fa;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.feature-card {
    background: var(--white);
    padding: 32px 24px;
    border-radius: 8px;
    text-align: center;
    transition: all 0.3s ease;
    border-top: 3px solid transparent;
}

.feature-card:hover {
    transform: translateY(-6px);
    box-shadow: 0 12px 32px rgba(0, 51, 153, 0.12);
    border-top-color: var(--accent);
}

.feature-icon {
    width: 64px;
    height: 64px;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    border-radius: 50%;
    margin: 0 auto 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 28px;
    color: var(--white);
}

.feature-card h3 {
    font-size: 18px;
    color: var(--primary);
    margin-bottom: 12px;
}

.feature-card p {
    font-size: 14px;
    color: var(--text-light);
    line-height: 1.7;
}

.products-preview {
    padding: 80px 0;
}

.products-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.product-card {
    background: var(--white);
    border: 1px solid #eee;
    border-radius: 8px;
    overflow: hidden;
    transition: all 0.3s ease;
}

.product-card:hover {
    box-shadow: 0 8px 24px rgba(0, 51, 153, 0.15);
    transform: translateY(-4px);
}

.product-img {
    width: 100%;
    height: 220px;
    overflow: hidden;
    background: #f0f0f0;
}

.product-img img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.4s ease;
}

.product-card:hover .product-img img {
    transform: scale(1.08);
}

.product-info {
    padding: 18px 18px 20px;
}

.product-info h3 {
    font-size: 16px;
    color: var(--primary);
    margin-bottom: 8px;
    font-weight: 600;
}

.product-info h3 a:hover {
    color: var(--secondary);
}

.product-info p {
    font-size: 13px;
    color: var(--text-light);
    line-height: 1.6;
    margin-bottom: 12px;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.product-info .more {
    font-size: 13px;
    color: var(--accent);
    font-weight: 500;
}

.product-info .more:hover {
    color: var(--primary);
}

.view-all {
    text-align: center;
    margin-top: 40px;
}

.about-preview {
    background: linear-gradient(135deg, #f5f7fa 0%, #e8edf5 100%);
}

.about-wrapper {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.about-img {
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 16px 48px rgba(0, 51, 153, 0.15);
}

.about-img img {
    width: 100%;
    height: 420px;
    object-fit: cover;
}

.about-content h2 {
    font-size: 32px;
    color: var(--primary);
    margin-bottom: 16px;
}

.about-content > p {
    color: var(--text-light);
    margin-bottom: 24px;
    line-height: 1.9;
}

.about-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
    margin-bottom: 28px;
}

.stat-item {
    text-align: center;
    padding: 18px 12px;
    background: var(--white);
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
}

.stat-item .num {
    font-size: 32px;
    font-weight: 700;
    color: var(--primary);
}

.stat-item .num small {
    font-size: 16px;
    color: var(--accent);
}

.stat-item .label {
    font-size: 13px;
    color: var(--text-light);
    margin-top: 4px;
}

.news-preview {
    padding: 80px 0;
}

.news-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.news-card {
    background: var(--white);
    border-radius: 8px;
    overflow: hidden;
    transition: all 0.3s ease;
    border: 1px solid #eee;
}

.news-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 10px 28px rgba(0, 51, 153, 0.12);
}

.news-img {
    width: 100%;
    height: 200px;
    overflow: hidden;
}

.news-img img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.news-info {
    padding: 20px;
}

.news-date {
    display: inline-block;
    font-size: 12px;
    color: var(--accent);
    background: rgba(255, 204, 0, 0.15);
    padding: 4px 10px;
    border-radius: 4px;
    margin-bottom: 12px;
}

.news-info h3 {
    font-size: 16px;
    color: var(--primary);
    margin-bottom: 10px;
    font-weight: 600;
    line-height: 1.5;
}

.news-info h3 a:hover {
    color: var(--secondary);
}

.news-info > p {
    font-size: 13px;
    color: var(--text-light);
    line-height: 1.7;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.banner {
    height: 240px;
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    position: relative;
    display: flex;
    align-items: center;
    color: var(--white);
    overflow: hidden;
}

.banner::before {
    content: '';
    position: absolute;
    inset: 0;
    background-size: cover;
    background-position: center;
    opacity: 0.2;
}

.banner-content {
    position: relative;
    z-index: 2;
    width: 100%;
}

.banner h1 {
    font-size: 36px;
    font-weight: 700;
    margin-bottom: 8px;
}

.banner p {
    font-size: 15px;
    opacity: 0.9;
}

.breadcrumb {
    margin-top: 16px;
    font-size: 13px;
    opacity: 0.85;
}

.breadcrumb a:hover {
    color: var(--accent);
}

.page-content {
    padding: 60px 0;
}

.sidebar-layout {
    display: grid;
    grid-template-columns: 260px 1fr;
    gap: 40px;
}

.sidebar-box {
    background: var(--white);
    border-radius: 8px;
    overflow: hidden;
    border: 1px solid #eee;
    margin-bottom: 24px;
}

.sidebar-title {
    padding: 18px 20px;
    background: var(--primary);
    color: var(--white);
    font-size: 16px;
    font-weight: 600;
}

.sidebar-menu li a {
    display: block;
    padding: 14px 20px;
    border-bottom: 1px solid #f0f0f0;
    color: var(--text);
    font-size: 14px;
    transition: all 0.2s ease;
}

.sidebar-menu li:last-child a {
    border-bottom: none;
}

.sidebar-menu li a:hover,
.sidebar-menu li a.active {
    background: rgba(0, 51, 153, 0.06);
    color: var(--primary);
    padding-left: 26px;
}

.list-page .products-grid,
.list-page .news-grid,
.list-page .cases-grid {
    grid-template-columns: repeat(3, 1fr);
}

.cases-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.case-card {
    background: var(--white);
    border-radius: 8px;
    overflow: hidden;
    border: 1px solid #eee;
    transition: all 0.3s ease;
}

.case-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 24px rgba(0, 51, 153, 0.12);
}

.case-img {
    width: 100%;
    height: 220px;
    overflow: hidden;
    position: relative;
}

.case-img img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.case-tag {
    position: absolute;
    top: 12px;
    left: 12px;
    background: var(--accent);
    color: var(--dark);
    padding: 4px 12px;
    font-size: 12px;
    border-radius: 4px;
    font-weight: 500;
}

.case-info {
    padding: 18px;
}

.case-info h3 {
    font-size: 16px;
    color: var(--primary);
    margin-bottom: 8px;
}

.case-info h3 a:hover {
    color: var(--secondary);
}

.case-info p {
    font-size: 13px;
    color: var(--text-light);
    line-height: 1.6;
}

.pagination {
    display: flex;
    justify-content: center;
    gap: 8px;
    margin-top: 50px;
}

.pagination a {
    padding: 8px 16px;
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 14px;
    color: var(--text);
}

.pagination a:hover,
.pagination a.active {
    background: var(--primary);
    color: var(--white);
    border-color: var(--primary);
}

.detail-article {
    background: var(--white);
    border-radius: 8px;
    padding: 40px;
}

.detail-header {
    text-align: center;
    border-bottom: 1px solid #eee;
    padding-bottom: 28px;
    margin-bottom: 32px;
}

.detail-header h1 {
    font-size: 28px;
    color: var(--primary);
    margin-bottom: 16px;
    line-height: 1.4;
}

.detail-meta {
    color: var(--text-light);
    font-size: 13px;
}

.detail-meta span {
    margin: 0 10px;
}

.detail-img {
    width: 100%;
    height: 420px;
    border-radius: 8px;
    overflow: hidden;
    margin-bottom: 32px;
}

.detail-img img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.detail-content h2 {
    font-size: 20px;
    color: var(--primary);
    margin: 28px 0 14px;
    padding-left: 14px;
    border-left: 4px solid var(--accent);
}

.detail-content h3 {
    font-size: 17px;
    color: var(--text);
    margin: 20px 0 10px;
}

.detail-content p {
    color: #444;
    margin-bottom: 16px;
    line-height: 1.9;
    text-indent: 2em;
}

.detail-content ul,
.detail-content ol {
    margin: 16px 0 16px 2em;
}

.detail-content li {
    margin-bottom: 10px;
    color: #444;
    line-height: 1.8;
}

.detail-content ul li::before {
    content: '▪';
    color: var(--accent);
    margin-right: 8px;
}

.detail-content ol {
    counter-reset: list-counter;
}

.detail-content ol li {
    counter-increment: list-counter;
    position: relative;
    padding-left: 24px;
}

.detail-content ol li::before {
    content: counter(list-counter);
    position: absolute;
    left: 0;
    color: var(--primary);
    font-weight: 600;
}

.detail-content table {
    width: 100%;
    border-collapse: collapse;
    margin: 20px 0;
    font-size: 14px;
}

.detail-content table th,
.detail-content table td {
    border: 1px solid #ddd;
    padding: 12px 16px;
    text-align: left;
}

.detail-content table th {
    background: rgba(0, 51, 153, 0.06);
    color: var(--primary);
    font-weight: 600;
}

.detail-nav {
    display: flex;
    justify-content: space-between;
    margin-top: 40px;
    padding-top: 24px;
    border-top: 1px solid #eee;
}

.detail-nav a {
    color: var(--text-light);
    font-size: 14px;
    max-width: 45%;
}

.detail-nav a:hover {
    color: var(--primary);
}

.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
}

.contact-info-box {
    padding: 40px;
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    border-radius: 12px;
    color: var(--white);
}

.contact-info-box h2 {
    font-size: 26px;
    margin-bottom: 28px;
    color: var(--white);
}

.contact-item {
    display: flex;
    gap: 16px;
    margin-bottom: 24px;
    align-items: flex-start;
}

.contact-icon {
    width: 44px;
    height: 44px;
    background: rgba(255, 255, 255, 0.15);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    font-size: 18px;
    color: var(--accent);
}

.contact-item h4 {
    font-size: 15px;
    margin-bottom: 4px;
    opacity: 0.9;
}

.contact-item p {
    font-size: 14px;
    opacity: 0.85;
    line-height: 1.7;
}

.contact-form-box {
    padding: 40px;
    background: var(--white);
    border-radius: 12px;
    border: 1px solid #eee;
}

.contact-form-box h2 {
    font-size: 26px;
    color: var(--primary);
    margin-bottom: 28px;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    font-size: 14px;
    color: var(--text);
    margin-bottom: 8px;
    font-weight: 500;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 12px 16px;
    border: 1px solid #ddd;
    border-radius: 6px;
    font-size: 14px;
    font-family: inherit;
    transition: all 0.3s ease;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--secondary);
    box-shadow: 0 0 0 3px rgba(51, 102, 204, 0.1);
}

.form-group textarea {
    resize: vertical;
    min-height: 120px;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}

.about-section {
    margin-bottom: 50px;
}

.about-section h2 {
    font-size: 24px;
    color: var(--primary);
    margin-bottom: 20px;
    padding-bottom: 12px;
    border-bottom: 2px solid var(--accent);
    display: inline-block;
}

.about-section p {
    line-height: 1.9;
    color: #444;
    margin-bottom: 16px;
    text-indent: 2em;
}

.timeline {
    position: relative;
    padding: 20px 0;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 50%;
    top: 0;
    bottom: 0;
    width: 3px;
    background: var(--gray);
    transform: translateX(-50%);
}

.timeline-item {
    position: relative;
    width: 50%;
    padding: 16px 40px;
}

.timeline-item:nth-child(odd) {
    left: 0;
    text-align: right;
    padding-right: 50px;
}

.timeline-item:nth-child(even) {
    left: 50%;
    padding-left: 50px;
}

.timeline-year {
    display: inline-block;
    padding: 6px 16px;
    background: var(--primary);
    color: var(--white);
    border-radius: 20px;
    font-size: 14px;
    font-weight: 600;
    margin-bottom: 10px;
}

.timeline-item:nth-child(even) .timeline-dot {
    left: -8px;
}

.timeline-item:nth-child(odd) .timeline-dot {
    right: -8px;
}

.timeline-dot {
    position: absolute;
    top: 24px;
    width: 16px;
    height: 16px;
    background: var(--accent);
    border: 3px solid var(--white);
    border-radius: 50%;
    box-shadow: 0 0 0 2px var(--primary);
}

.timeline-content {
    background: var(--white);
    padding: 18px 20px;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.06);
}

.timeline-content h4 {
    color: var(--primary);
    margin-bottom: 6px;
}

.timeline-content p {
    font-size: 14px;
    color: var(--text-light);
    text-indent: 0;
    margin: 0;
}

.footer {
    background: #0a1a3d;
    color: #b8c5e0;
    padding: 60px 0 0;
}

.footer-grid {
    display: grid;
    grid-template-columns: 1.5fr 1fr 1fr 1.2fr;
    gap: 40px;
    padding-bottom: 40px;
}

.footer-col h3 {
    color: var(--white);
    font-size: 16px;
    margin-bottom: 20px;
    padding-bottom: 12px;
    border-bottom: 2px solid var(--accent);
    display: inline-block;
}

.footer-about .logo-text {
    color: var(--white);
    margin-bottom: 14px;
}

.footer-about p {
    font-size: 13px;
    line-height: 1.8;
    opacity: 0.85;
    margin-bottom: 16px;
}

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

.footer-links a {
    font-size: 13px;
    opacity: 0.85;
}

.footer-links a:hover {
    color: var(--accent);
    padding-left: 6px;
}

.footer-contact p {
    font-size: 13px;
    line-height: 2;
    opacity: 0.85;
}

.footer-contact i {
    color: var(--accent);
    margin-right: 8px;
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding: 20px 0;
    text-align: center;
    font-size: 13px;
    opacity: 0.8;
}

.footer-bottom p {
    margin-bottom: 6px;
}

.back-top {
    position: fixed;
    right: 24px;
    bottom: 80px;
    width: 44px;
    height: 44px;
    background: var(--primary);
    color: var(--white);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    font-size: 18px;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    z-index: 999;
    box-shadow: 0 4px 12px rgba(0, 51, 153, 0.3);
}

.back-top.show {
    opacity: 1;
    visibility: visible;
}

.back-top:hover {
    background: var(--secondary);
    transform: translateY(-3px);
}

@media (max-width: 992px) {
    .features-grid,
    .products-grid,
    .cases-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .news-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .about-wrapper {
        grid-template-columns: 1fr;
        gap: 40px;
    }
    .about-img img {
        height: 340px;
    }
    .sidebar-layout {
        grid-template-columns: 1fr;
    }
    .footer-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .contact-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .section {
        padding: 50px 0;
    }
    .section-title h2 {
        font-size: 24px;
    }
    .top-bar .container {
        justify-content: center;
        text-align: center;
    }
    .nav ul {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: var(--white);
        flex-direction: column;
        padding: 12px 20px;
        box-shadow: 0 4px 12px rgba(0,0,0,0.1);
    }
    .nav ul.open {
        display: flex;
    }
    .nav .menu-toggle {
        display: block;
    }
    .hero {
        height: 420px;
    }
    .hero-content h1 {
        font-size: 28px;
    }
    .hero-content p {
        font-size: 15px;
    }
    .banner {
        height: 180px;
    }
    .banner h1 {
        font-size: 26px;
    }
    .features-grid,
    .products-grid,
    .news-grid,
    .cases-grid {
        grid-template-columns: 1fr;
    }
    .about-stats {
        grid-template-columns: repeat(3, 1fr);
        gap: 10px;
    }
    .stat-item .num {
        font-size: 24px;
    }
    .timeline::before {
        left: 20px;
    }
    .timeline-item,
    .timeline-item:nth-child(odd),
    .timeline-item:nth-child(even) {
        width: 100%;
        left: 0;
        text-align: left;
        padding: 12px 0 12px 50px;
    }
    .timeline-item:nth-child(odd) .timeline-dot,
    .timeline-item:nth-child(even) .timeline-dot {
        left: 12px;
        right: auto;
    }
    .footer-grid {
        grid-template-columns: 1fr;
        gap: 30px;
    }
    .form-row {
        grid-template-columns: 1fr;
    }
    .detail-article {
        padding: 24px 20px;
    }
    .detail-header h1 {
        font-size: 22px;
    }
    .detail-img {
        height: 260px;
    }
    .hero-buttons {
        flex-direction: column;
    }
    .hero-buttons .btn {
        width: 100%;
        text-align: center;
    }
}