/* ==================== 基础重置与变量 ==================== */
:root {
    --primary: #1a4b8c;          /* 企业蓝，与总公司一致 */
    --primary-dark: #123a6d;
    --primary-light: #2e6ab8;
    --accent: #00a8e6;
    --text: #333333;
    --text-light: #666666;
    --text-lighter: #999999;
    --bg: #ffffff;
    --bg-gray: #f5f7fa;
    --border: #e5e5e5;
    --shadow: 0 2px 12px rgba(0, 0, 0, 0.08);
    --shadow-hover: 0 8px 24px rgba(0, 0, 0, 0.12);
    --radius: 8px;
    --wrap-width: 1200px;
    --header-height: 80px;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
    font-size: 15px;
    line-height: 1.6;
    color: var(--text);
    background: var(--bg);
}

a {
    text-decoration: none;
    color: inherit;
}

ul, ol {
    list-style: none;
}

img {
    max-width: 100%;
    vertical-align: middle;
}

.wrap {
    width: 92%;
    max-width: var(--wrap-width);
    margin: 0 auto;
}

/* ==================== 动画 ==================== */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.wow {
    visibility: hidden;
}

.wow.animated {
    visibility: visible;
    animation: fadeInUp 0.6s ease forwards;
}

/* ==================== 按钮 ==================== */
.btn {
    display: inline-block;
    padding: 12px 32px;
    border-radius: 4px;
    font-size: 15px;
    cursor: pointer;
    transition: all 0.3s ease;
    border: none;
    font-family: inherit;
}

.btn-primary {
    background: var(--primary);
    color: #fff;
}

.btn-primary:hover {
    background: var(--primary-dark);
}

.btn-outline {
    background: transparent;
    color: #fff;
    border: 1px solid rgba(255, 255, 255, 0.6);
}

.btn-outline:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: #fff;
}

.btn-block {
    width: 100%;
}

.btn-small {
    display: inline-block;
    padding: 6px 16px;
    border: 1px solid var(--primary);
    color: var(--primary);
    border-radius: 4px;
    font-size: 13px;
    cursor: pointer;
    transition: all 0.3s ease;
}

.btn-small:hover {
    background: var(--primary);
    color: #fff;
}

.btn-small.btn-outline {
    border-color: var(--border);
    color: var(--text-light);
}

.btn-small.btn-outline:hover {
    border-color: var(--primary);
    color: var(--primary);
    background: transparent;
}

/* ==================== 头部导航 ==================== */
.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: var(--header-height);
    background: rgba(255, 255, 255, 0.95);
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
    z-index: 1000;
    transition: all 0.3s ease;
}

.header-box {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
}

.logo a {
    display: flex;
    align-items: center;
}

.logo-img {
    display: block;
    height: 28px;
    width: auto;
    max-width: 100%;
}

.nav ul {
    display: flex;
    gap: 40px;
}

.nav a {
    font-size: 15px;
    color: var(--text);
    position: relative;
    padding: 8px 0;
    transition: color 0.3s ease;
}

.nav a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary);
    transition: width 0.3s ease;
}

.nav a:hover,
.nav li.on a {
    color: var(--primary);
}

.nav a:hover::after,
.nav li.on a::after {
    width: 100%;
}

.menu-btn {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
    padding: 10px;
}

.menu-btn .line {
    width: 24px;
    height: 2px;
    background: var(--text);
    transition: all 0.3s ease;
}

/* ==================== Hero Banner ==================== */
.hero {
    position: relative;
    min-height: 680px;
    display: flex;
    align-items: center;
    padding-top: var(--header-height);
    background: linear-gradient(135deg, #0d2b4e 0%, #1a4b8c 50%, #0d6c9e 100%);
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background:
        radial-gradient(circle at 20% 80%, rgba(0, 168, 230, 0.15) 0%, transparent 40%),
        radial-gradient(circle at 80% 20%, rgba(255, 255, 255, 0.08) 0%, transparent 40%);
}

.hero-content {
    position: relative;
    z-index: 2;
    color: #fff;
    max-width: 800px;
}

.hero-logo {
    display: block;
    height: 68px;
    width: auto;
    margin-bottom: 24px;
}

.hero-title {
    font-size: 48px;
    font-weight: 700;
    margin-bottom: 20px;
    line-height: 1.2;
}

.hero-subtitle {
    font-size: 24px;
    font-weight: 300;
    margin-bottom: 24px;
    opacity: 0.95;
}

.hero-desc {
    font-size: 16px;
    line-height: 1.8;
    margin-bottom: 36px;
    opacity: 0.85;
    max-width: 680px;
}

.hero-btns {
    display: flex;
    gap: 20px;
}

.hero-btns .btn-primary {
    background: #fff;
    color: var(--primary);
}

.hero-btns .btn-primary:hover {
    background: rgba(255, 255, 255, 0.9);
}

/* ==================== 四大入口 ==================== */
.quick-entry {
    padding: 60px 0;
    background: var(--bg);
    margin-top: -60px;
    position: relative;
    z-index: 10;
}

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

.entry-card {
    background: #fff;
    border-radius: var(--radius);
    padding: 32px 24px;
    box-shadow: var(--shadow);
    transition: all 0.3s ease;
    border-top: 3px solid transparent;
}

.entry-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-hover);
    border-top-color: var(--primary);
}

.entry-icon {
    width: 56px;
    height: 56px;
    border-radius: 12px;
    margin-bottom: 20px;
    background: var(--bg-gray);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    color: var(--primary);
}

.entry-icon.icon-product::before { content: '🔬'; }
.entry-icon.icon-solution::before { content: '📋'; }
.entry-icon.icon-contact::before { content: '📞'; }
.entry-icon.icon-ai::before { content: '🤖'; }

.entry-card h3 {
    font-size: 18px;
    margin-bottom: 10px;
    color: var(--text);
}

.entry-card p {
    font-size: 13px;
    color: var(--text-light);
    line-height: 1.6;
    margin-bottom: 16px;
}

.entry-arrow {
    font-size: 13px;
    color: var(--primary);
    font-weight: 500;
}

/* ==================== 通用区块 ==================== */
.section {
    padding: 80px 0;
}

.section-header {
    text-align: center;
    margin-bottom: 48px;
}

.section-title {
    font-size: 36px;
    font-weight: 700;
    color: var(--text);
    margin-bottom: 16px;
    position: relative;
    display: inline-block;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 48px;
    height: 3px;
    background: var(--primary);
}

.section-subtitle {
    font-size: 16px;
    color: var(--text-light);
    margin-top: 24px;
}

/* ==================== Tab 导航 ==================== */
.tab-nav {
    display: flex;
    justify-content: center;
    gap: 12px;
    margin-bottom: 40px;
    flex-wrap: wrap;
}

.tab-btn {
    padding: 10px 24px;
    border: 1px solid var(--border);
    background: #fff;
    color: var(--text);
    border-radius: 4px;
    cursor: pointer;
    font-size: 14px;
    transition: all 0.3s ease;
    font-family: inherit;
}

.tab-btn:hover,
.tab-btn.active {
    background: var(--primary);
    color: #fff;
    border-color: var(--primary);
}

.tab-panel {
    display: none;
}

.tab-panel.active {
    display: block;
    animation: fadeInUp 0.4s ease;
}

/* ==================== 产品矩阵 ==================== */
.products {
    background: var(--bg-gray);
}

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

.product-card {
    background: #fff;
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: all 0.3s ease;
    padding-bottom: 24px;
}

.product-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-hover);
}

.product-img {
    width: 100%;
    height: 200px;
    background: linear-gradient(135deg, #e8f1f8 0%, #d4e6f3 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--primary);
    font-size: 24px;
    font-weight: 700;
    margin-bottom: 20px;
}

img.product-img {
    object-fit: cover;
    display: block;
}

.product-card h3 {
    font-size: 18px;
    padding: 0 24px;
    margin-bottom: 12px;
    color: var(--text);
}

.product-card p {
    font-size: 14px;
    color: var(--text-light);
    padding: 0 24px;
    line-height: 1.7;
    margin-bottom: 16px;
}

.product-link {
    display: inline-block;
    margin-left: 24px;
    color: var(--primary);
    font-size: 14px;
    font-weight: 500;
}

.product-link::after {
    content: ' →';
}

/* ==================== 解决方案 ==================== */
.solutions {
    background: var(--bg);
}

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

.solution-card {
    background: #fff;
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: all 0.3s ease;
    border: 1px solid var(--border);
}

.solution-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-hover);
}

.solution-img {
    width: 100%;
    height: 160px;
    background: linear-gradient(135deg, #f0f4f8 0%, #e1eaf3 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--primary);
    font-size: 20px;
    font-weight: 700;
}

.solution-card h3 {
    font-size: 15px;
    padding: 20px 20px 0;
    margin-bottom: 16px;
    color: var(--text);
    line-height: 1.5;
    min-height: 70px;
}

.solution-actions {
    padding: 0 20px 20px;
    display: flex;
    gap: 10px;
}

/* ==================== 联系我们 ==================== */
.contact {
    background: var(--bg-gray);
}

.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
}

.contact-info,
.contact-form {
    background: #fff;
    border-radius: var(--radius);
    padding: 40px;
    box-shadow: var(--shadow);
}

.contact-info h3,
.contact-form h3 {
    font-size: 22px;
    margin-bottom: 24px;
    color: var(--text);
}

.contact-table {
    width: 100%;
    border-collapse: collapse;
}

.contact-table th,
.contact-table td {
    padding: 14px 0;
    text-align: left;
    border-bottom: 1px solid var(--border);
    font-size: 14px;
}

.contact-table th {
    width: 80px;
    color: var(--text-light);
    font-weight: normal;
}

.contact-table td {
    color: var(--text);
}

.placeholder-text {
    color: var(--text-lighter);
    font-style: italic;
}

.qr-area {
    display: flex;
    gap: 24px;
    margin-top: 28px;
}

.qr-box {
    text-align: center;
}

.qr-placeholder {
    width: 100px;
    height: 100px;
    background: var(--bg-gray);
    border: 1px dashed var(--border);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-lighter);
    font-size: 13px;
    margin-bottom: 8px;
}

.qr-placeholder.small {
    width: 80px;
    height: 80px;
}

.qr-box p {
    font-size: 12px;
    color: var(--text-light);
}

.form-tip {
    color: var(--text-lighter);
    font-size: 13px;
    margin-bottom: 20px;
}

.form-group {
    margin-bottom: 18px;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 12px 16px;
    border: 1px solid var(--border);
    border-radius: 4px;
    font-size: 14px;
    font-family: inherit;
    transition: border-color 0.3s ease;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary);
}

/* ==================== AI 方案 ==================== */
.ai-section {
    background: linear-gradient(180deg, #f8fafc 0%, #ffffff 100%);
}

.ai-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
    margin-bottom: 60px;
}

.ai-card {
    background: #fff;
    border-radius: var(--radius);
    padding: 36px 28px;
    box-shadow: var(--shadow);
    position: relative;
    overflow: hidden;
    transition: all 0.3s ease;
    border-top: 4px solid var(--primary);
}

.ai-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-hover);
}

.ai-tag {
    position: absolute;
    top: 16px;
    right: -28px;
    background: #ff6b6b;
    color: #fff;
    font-size: 12px;
    padding: 4px 30px;
    transform: rotate(45deg);
}

.ai-icon {
    width: 64px;
    height: 64px;
    border-radius: 16px;
    background: var(--bg-gray);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 28px;
    margin-bottom: 20px;
}

.ai-icon.icon-ai-1::before { content: '🧠'; }
.ai-icon.icon-ai-2::before { content: '🔧'; }
.ai-icon.icon-ai-3::before { content: '📊'; }

.ai-card h3 {
    font-size: 20px;
    margin-bottom: 14px;
    color: var(--text);
}

.ai-card p {
    font-size: 14px;
    color: var(--text-light);
    line-height: 1.7;
    margin-bottom: 18px;
}

.ai-features {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 8px;
}

.ai-features li {
    font-size: 13px;
    color: var(--text);
    padding-left: 16px;
    position: relative;
}

.ai-features li::before {
    content: '•';
    position: absolute;
    left: 0;
    color: var(--primary);
    font-weight: bold;
}

/* AI 应用框架 */
.ai-framework {
    background: #fff;
    border-radius: var(--radius);
    padding: 48px;
    box-shadow: var(--shadow);
    text-align: center;
}

.ai-framework h3 {
    font-size: 24px;
    margin-bottom: 36px;
    color: var(--text);
}

.framework-diagram {
    max-width: 800px;
    margin: 0 auto;
}

.framework-layer {
    background: var(--bg-gray);
    border-radius: var(--radius);
    padding: 24px;
    border-left: 4px solid var(--primary);
}

.layer-title {
    font-size: 16px;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 14px;
}

.layer-items {
    display: flex;
    justify-content: center;
    gap: 12px;
    flex-wrap: wrap;
}

.layer-items span {
    background: #fff;
    padding: 8px 16px;
    border-radius: 20px;
    font-size: 13px;
    color: var(--text);
    border: 1px solid var(--border);
}

.framework-arrow {
    font-size: 24px;
    color: var(--primary);
    margin: 12px 0;
    opacity: 0.6;
}

.framework-note {
    margin-top: 28px;
    color: var(--text-lighter);
    font-size: 14px;
}

/* ==================== Footer ==================== */
.footer {
    background: #1a1a2e;
    color: #fff;
    padding: 60px 0 24px;
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1.5fr 1fr;
    gap: 40px;
    margin-bottom: 40px;
}

.footer-brand h3 {
    font-size: 20px;
    margin-bottom: 12px;
}

.footer-logo {
    display: block;
    height: 56px;
    width: auto;
    margin-bottom: 14px;
}

.footer-brand p {
    color: rgba(255, 255, 255, 0.7);
    font-size: 14px;
    margin-bottom: 8px;
}

.footer-desc {
    margin-top: 16px;
    line-height: 1.8;
}

.footer-links h4,
.footer-contact h4,
.footer-qr h4 {
    font-size: 16px;
    margin-bottom: 20px;
    color: #fff;
}

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

.footer-links a {
    color: rgba(255, 255, 255, 0.7);
    font-size: 14px;
    transition: color 0.3s ease;
}

.footer-links a:hover {
    color: #fff;
}

.footer-contact p {
    color: rgba(255, 255, 255, 0.7);
    font-size: 14px;
    margin-bottom: 10px;
}

.footer-contact .placeholder-text {
    color: rgba(255, 255, 255, 0.4);
}

.footer-qr .qr-placeholder {
    background: rgba(255, 255, 255, 0.1);
    border-color: rgba(255, 255, 255, 0.2);
    color: rgba(255, 255, 255, 0.5);
}

.footer-qr p {
    color: rgba(255, 255, 255, 0.7);
    font-size: 12px;
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: 24px;
    text-align: center;
}

.footer-bottom p {
    color: rgba(255, 255, 255, 0.5);
    font-size: 13px;
    margin-bottom: 6px;
}

/* ==================== 返回顶部 ==================== */
.gotop {
    position: fixed;
    right: 30px;
    bottom: 30px;
    width: 44px;
    height: 44px;
    background: var(--primary);
    color: #fff;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    z-index: 999;
    font-size: 18px;
}

.gotop.show {
    opacity: 1;
    visibility: visible;
}

.gotop:hover {
    background: var(--primary-dark);
}

/* ==================== 响应式 ==================== */
@media (max-width: 1024px) {
    .entry-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .product-grid,
    .solution-list,
    .ai-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .footer-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    :root {
        --header-height: 64px;
    }

    .header-box {
        padding: 0 4%;
    }

    .menu-btn {
        display: flex;
    }

    .nav {
        position: fixed;
        top: var(--header-height);
        left: 0;
        width: 100%;
        height: calc(100vh - var(--header-height));
        background: #fff;
        padding: 20px 0;
        transform: translateX(100%);
        transition: transform 0.3s ease;
        overflow-y: auto;
    }

    .nav.open {
        transform: translateX(0);
    }

    .nav ul {
        flex-direction: column;
        gap: 0;
    }

    .nav li {
        border-bottom: 1px solid var(--border);
    }

    .nav a {
        display: block;
        padding: 16px 24px;
    }

    .nav a::after {
        display: none;
    }

    .hero {
        min-height: 520px;
    }

    .hero-title {
        font-size: 32px;
    }

    .hero-subtitle {
        font-size: 18px;
    }

    .logo-img {
        height: 18px;
    }

    .hero-logo {
        height: 52px;
    }

    .hero-btns {
        flex-direction: column;
        gap: 12px;
    }

    .entry-grid,
    .product-grid,
    .solution-list,
    .ai-grid {
        grid-template-columns: 1fr;
    }

    .contact-grid {
        grid-template-columns: 1fr;
    }

    .footer-grid {
        grid-template-columns: 1fr;
        gap: 32px;
    }

    .tab-nav {
        gap: 8px;
    }

    .tab-btn {
        padding: 8px 16px;
        font-size: 13px;
    }

    .ai-framework {
        padding: 28px;
    }

    .layer-items {
        gap: 8px;
    }

    .layer-items span {
        padding: 6px 12px;
        font-size: 12px;
    }
}

@media (max-width: 480px) {
    .section {
        padding: 48px 0;
    }

    .section-title {
        font-size: 26px;
    }

    .entry-card {
        padding: 24px;
    }

    .contact-info,
    .contact-form {
        padding: 24px;
    }
}