/* ===== Reset & Base ===== */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
    font-family: "Microsoft YaHei", "PingFang SC", "Helvetica Neue", Arial, sans-serif;
    color: #333;
    line-height: 1.6;
    background: #fff;
    overflow-x: hidden;
}
a { text-decoration: none; color: inherit; }
ul { list-style: none; }
img { max-width: 100%; display: block; }
.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }

/* ===== Variables ===== */
:root {
    --primary: #0072BC;
    --primary-dark: #003D6B;
    --primary-light: #E8F4FB;
    --accent: #4ECDC4;
    --accent-dark: #2BB6AC;
    --text: #333333;
    --text-light: #666666;
    --text-muted: #999999;
    --bg-gray: #F5F7FA;
    --border: #E0E0E0;
    --white: #FFFFFF;
    --shadow: 0 4px 20px rgba(0,0,0,0.08);
    --shadow-lg: 0 8px 40px rgba(0,0,0,0.12);
    --radius: 8px;
    --radius-lg: 16px;
    --transition: all 0.3s ease;
}

/* ===== Header ===== */
.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background: rgba(255,255,255,0.95);
    backdrop-filter: blur(10px);
    box-shadow: 0 2px 10px rgba(0,0,0,0.06);
    transition: var(--transition);
}
.header-inner {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
}
.logo {
    display: flex;
    align-items: center;
    gap: 10px;
}
.logo-icon {
    width: 44px;
    height: 44px;
    background: linear-gradient(135deg, var(--primary), var(--accent));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    font-size: 18px;
    font-weight: 700;
}
.logo-text {
    display: flex;
    flex-direction: column;
    line-height: 1.2;
}
.logo-text .cn { font-size: 18px; font-weight: 700; color: var(--primary-dark); }
.logo-text .en { font-size: 12px; color: var(--text-muted); letter-spacing: 2px; text-transform: uppercase; }

/* New: 图片 LOGO 样式 */
.logo-img {
    height: 48px;
    width: auto;
    display: block;
}
.logo-img-light {
    /* 深色底色上使用：反色让蓝色 LOGO 变白色 */
    filter: brightness(0) invert(1);
    height: 56px;
}

.nav { display: flex; align-items: center; gap: 4px; }
.nav a {
    padding: 8px 16px;
    font-size: 15px;
    color: var(--text);
    border-radius: 6px;
    transition: var(--transition);
    position: relative;
}
.nav a:hover, .nav a.active {
    color: var(--primary);
    background: var(--primary-light);
}
.nav a.active::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 50%;
    transform: translateX(-50%);
    width: 20px;
    height: 3px;
    background: var(--primary);
    border-radius: 2px;
}
.nav-cta {
    margin-left: 12px;
    padding: 8px 22px !important;
    background: var(--primary) !important;
    color: #fff !important;
    border-radius: 24px !important;
    font-weight: 500;
}
.nav-cta:hover { background: var(--primary-dark) !important; color: #fff !important; }

/* 导航下拉菜单（产品中心分类） */
.nav-dropdown { position: relative; display: inline-flex; align-items: center; }
/* 有下拉菜单的主导航项：文字后加下拉标识（默认朝下，悬停/展开时翻转朝上并变主题色） */
.nav-dropdown > a { padding-right: 30px; }
.nav-dropdown::after {
    content: "";
    position: absolute;
    right: 14px;
    top: 50%;
    width: 6px;
    height: 6px;
    border-right: 1.6px solid currentColor;
    border-bottom: 1.6px solid currentColor;
    color: var(--text);
    transform: translateY(-70%) rotate(45deg);
    transition: transform 0.25s ease, color 0.25s ease;
    pointer-events: none;
}
.nav-dropdown:hover::after,
.nav-dropdown:focus-within::after {
    color: var(--primary);
    transform: translateY(-30%) rotate(225deg);
}
.nav-dropdown-menu {
    position: absolute;
    top: 100%;
    left: 0;
    min-width: 176px;
    background: #fff;
    border: 1px solid var(--border, #eee);
    border-radius: 8px;
    box-shadow: var(--shadow-lg, 0 8px 24px rgba(0,0,0,.12));
    padding: 6px 0;
    display: none;
    z-index: 999;
}
.nav-dropdown:hover .nav-dropdown-menu,
.nav-dropdown:focus-within .nav-dropdown-menu { display: block; }
.nav-dropdown-menu a {
    display: block;
    padding: 10px 18px;
    font-size: 14px;
    white-space: nowrap;
    border-radius: 0;
    color: var(--text);
}
.nav-dropdown-menu a:hover {
    background: var(--primary-light);
    color: var(--primary);
}
.nav-dropdown-menu a.active::after { display: none; }

/* 锚点定位时预留固定导航高度 */
section[id], .solution-item[id] { scroll-margin-top: 92px; }

.menu-toggle { display: none; font-size: 26px; cursor: pointer; color: var(--primary-dark); }

/* ===== Hero Section ===== */
.hero {
    position: relative;
    min-height: 600px;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    overflow: hidden;
    background: linear-gradient(135deg, #003D6B 0%, #0072BC 50%, #4ECDC4 100%);
    color: #fff;
}
.hero::before {
    content: '';
    position: absolute;
    top: 0; left: 0; right: 0; bottom: 0;
    background: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='1600' height='600' viewBox='0 0 1600 600'%3E%3Cg fill='none' stroke='%23ffffff' stroke-opacity='0.06' stroke-width='1'%3E%3Ccircle cx='200' cy='150' r='120'/%3E%3Ccircle cx='500' cy='400' r='90'/%3E%3Ccircle cx='900' cy='200' r='150'/%3E%3Ccircle cx='1300' cy='350' r='100'/%3E%3Ccircle cx='1100' cy='100' r='70'/%3E%3C/g%3E%3C/svg%3E") center/cover;
}
.hero-content { position: relative; z-index: 2; max-width: 900px; padding: 120px 20px 80px; }
.hero h1 {
    font-size: 42px;
    font-weight: 700;
    margin-bottom: 20px;
    letter-spacing: 2px;
    animation: fadeInUp 1s ease;
}
.hero .subtitle {
    font-size: 20px;
    opacity: 0.9;
    margin-bottom: 12px;
    animation: fadeInUp 1s ease 0.2s backwards;
}
.hero .desc {
    font-size: 15px;
    opacity: 0.75;
    margin-bottom: 36px;
    animation: fadeInUp 1s ease 0.4s backwards;
}
.hero-btns { display: flex; gap: 16px; justify-content: center; animation: fadeInUp 1s ease 0.6s backwards; }
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 12px 32px;
    border-radius: 30px;
    font-size: 15px;
    font-weight: 500;
    transition: var(--transition);
    cursor: pointer;
    border: none;
}
.btn-primary { background: var(--accent); color: #fff; }
.btn-primary:hover { background: var(--accent-dark); transform: translateY(-2px); box-shadow: 0 6px 20px rgba(78,205,196,0.4); }
.btn-outline { background: transparent; color: #fff; border: 2px solid rgba(255,255,255,0.6); }
.btn-outline:hover { background: rgba(255,255,255,0.15); border-color: #fff; }
.btn-dark { background: var(--primary); color: #fff; }
.btn-dark:hover { background: var(--primary-dark); transform: translateY(-2px); box-shadow: var(--shadow); }

/* ===== Page Banner (inner pages) ===== */
.page-hero {
    position: relative;
    min-height: 340px;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    color: #fff;
    background: linear-gradient(135deg, #003D6B 0%, #0072BC 100%);
    overflow: hidden;
}
.page-hero::before {
    content: '';
    position: absolute;
    top: 0; right: 0; bottom: 0; left: 0;
    background: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='1600' height='340' viewBox='0 0 1600 340'%3E%3Cg fill='none' stroke='%23ffffff' stroke-opacity='0.06' stroke-width='1'%3E%3Ccircle cx='300' cy='120' r='100'/%3E%3Ccircle cx='800' cy='200' r='130'/%3E%3Ccircle cx='1200' cy='80' r='90'/%3E%3C/g%3E%3C/svg%3E") center/cover;
}
.page-hero-content { position: relative; z-index: 2; padding: 120px 20px 60px; }
.page-hero h1 { font-size: 36px; font-weight: 700; margin-bottom: 10px; }
.page-hero .breadcrumb { font-size: 14px; opacity: 0.8; }
.page-hero .breadcrumb a:hover { text-decoration: underline; }

/* ===== Section General ===== */
.section { padding: 80px 0; }
.section-gray { background: var(--bg-gray); }
.section-header { text-align: center; margin-bottom: 50px; }
.section-header .label { color: var(--accent); font-size: 14px; font-weight: 600; text-transform: uppercase; letter-spacing: 3px; margin-bottom: 8px; }
.section-header h2 { font-size: 32px; font-weight: 700; color: var(--text); margin-bottom: 12px; }
.section-header p { font-size: 15px; color: var(--text-light); max-width: 700px; margin: 0 auto; }
.section-header .divider {
    width: 50px;
    height: 4px;
    background: linear-gradient(90deg, var(--primary), var(--accent));
    border-radius: 2px;
    margin: 16px auto;
}

/* ===== Five Domains ===== */
.domains-grid {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 20px;
}
.domain-card {
    background: #fff;
    border-radius: var(--radius-lg);
    padding: 36px 24px;
    text-align: center;
    transition: var(--transition);
    box-shadow: var(--shadow);
    cursor: pointer;
}
.domain-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
}
.domain-icon {
    width: 72px;
    height: 72px;
    margin: 0 auto 20px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 32px;
    background: linear-gradient(135deg, var(--primary-light), #d0e9f7);
    transition: var(--transition);
}
.domain-card:hover .domain-icon {
    background: linear-gradient(135deg, var(--primary), var(--accent));
    color: #fff;
}
.domain-card h3 { font-size: 18px; font-weight: 600; margin-bottom: 8px; color: var(--text); }
.domain-card p { font-size: 13px; color: var(--text-light); line-height: 1.5; }

/* ===== Brand Story ===== */
.brand-story {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}
.brand-story-text .year {
    font-size: 64px;
    font-weight: 800;
    color: var(--primary);
    opacity: 0.15;
    line-height: 1;
    margin-bottom: -20px;
}
.brand-story-text h2 { font-size: 28px; font-weight: 700; margin-bottom: 16px; color: var(--text); }
.brand-story-text p { font-size: 15px; color: var(--text-light); margin-bottom: 14px; line-height: 1.8; }
.brand-story-visual {
    position: relative;
    border-radius: var(--radius-lg);
    overflow: hidden;
    min-height: 400px;
    background: linear-gradient(135deg, #003D6B, #0072BC);
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
}
.brand-story-visual svg { width: 100%; height: 100%; }

/* ===== Stats ===== */
.stats {
    background: linear-gradient(135deg, #003D6B, #0072BC);
    color: #fff;
    padding: 60px 0;
}
.stats-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 30px;
    text-align: center;
}
.stat-item .num { font-size: 44px; font-weight: 800; color: var(--accent); }
.stat-item .num small { font-size: 20px; }
.stat-item .label { font-size: 15px; opacity: 0.85; margin-top: 6px; }

/* ===== Product Cards ===== */
.products-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}
.product-card {
    background: #fff;
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
    cursor: pointer;
}
.product-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-lg);
}
.product-card .product-visual {
    height: 220px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #f0f7fc, #d0e9f7);
    font-size: 56px;
    color: var(--primary);
    transition: var(--transition);
    overflow: hidden;
    padding: 20px;
}
.product-card .product-visual img {
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
    display: block;
}
.product-card:hover .product-visual {
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: #fff;
}
.product-card .product-body { padding: 24px; }
.product-card .product-body h3 { font-size: 18px; font-weight: 600; margin-bottom: 8px; }
.product-card .product-body p { font-size: 14px; color: var(--text-light); margin-bottom: 12px; }
.product-card .product-tag {
    display: inline-block;
    padding: 3px 12px;
    background: var(--primary-light);
    color: var(--primary);
    border-radius: 20px;
    font-size: 12px;
}

/* ===== Certifications ===== */
.cert-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}
.cert-group {
    background: #fff;
    border-radius: var(--radius-lg);
    padding: 32px;
    box-shadow: var(--shadow);
}
.cert-group h3 {
    font-size: 18px;
    font-weight: 600;
    margin-bottom: 16px;
    display: flex;
    align-items: center;
    gap: 10px;
}
.cert-group h3 .cert-icon { font-size: 24px; }
.cert-group ul li {
    padding: 6px 0;
    font-size: 14px;
    color: var(--text-light);
    border-bottom: 1px solid #f0f0f0;
}
.cert-group ul li:last-child { border-bottom: none; }
.cert-group ul li::before {
    content: '✓';
    color: var(--accent);
    font-weight: 700;
    margin-right: 8px;
}

/* ===== Cases ===== */
.cases-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}
.case-card {
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
    background: #fff;
    cursor: pointer;
}
.case-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); }
.case-card .case-visual {
    height: 200px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 48px;
    color: #fff;
}
.case-card .case-body { padding: 20px; }
.case-card .case-body h3 { font-size: 16px; font-weight: 600; margin-bottom: 6px; }
.case-card .case-body p { font-size: 13px; color: var(--text-light); }

/* ===== News ===== */
.news-list { display: flex; flex-direction: column; gap: 20px; }
.news-item {
    display: flex;
    gap: 24px;
    background: #fff;
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
    cursor: pointer;
}
.news-item:hover { box-shadow: var(--shadow-lg); transform: translateX(4px); }
.news-date {
    flex-shrink: 0;
    width: 100px;
    text-align: center;
    padding: 20px;
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: #fff;
}
.news-date .day { font-size: 28px; font-weight: 700; }
.news-date .month { font-size: 13px; opacity: 0.8; }
.news-content { padding: 20px; flex: 1; }
.news-content h3 { font-size: 17px; margin-bottom: 8px; transition: var(--transition); }
.news-item:hover .news-content h3 { color: var(--primary); }
.news-content p { font-size: 14px; color: var(--text-light); }

/* ===== Solutions ===== */
.solution-item {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
    align-items: center;
    margin-bottom: 60px;
}
.solution-item:nth-child(even) { direction: rtl; }
.solution-item:nth-child(even) > * { direction: ltr; }
.solution-visual {
    min-height: 300px;
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 64px;
    color: #fff;
}
.solution-text h3 { font-size: 24px; font-weight: 700; margin-bottom: 14px; }
.solution-text p { font-size: 15px; color: var(--text-light); margin-bottom: 12px; line-height: 1.8; }
.solution-features { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 16px; }
.solution-features span {
    padding: 6px 16px;
    background: var(--primary-light);
    color: var(--primary);
    border-radius: 20px;
    font-size: 13px;
    font-weight: 500;
}

/* ===== Contact ===== */
.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
}
.contact-info h3 { font-size: 22px; margin-bottom: 20px; color: var(--text); }
.contact-info-item {
    display: flex;
    gap: 16px;
    margin-bottom: 24px;
    align-items: flex-start;
}
.contact-info-item .ci-icon {
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: var(--primary-light);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    color: var(--primary);
    flex-shrink: 0;
}
.contact-info-item .ci-text h4 { font-size: 15px; font-weight: 600; margin-bottom: 4px; }
.contact-info-item .ci-text p { font-size: 14px; color: var(--text-light); line-height: 1.6; }
.contact-form {
    background: #fff;
    border-radius: var(--radius-lg);
    padding: 36px;
    box-shadow: var(--shadow);
}
.form-group { margin-bottom: 20px; }
.form-group label { display: block; font-size: 14px; font-weight: 500; margin-bottom: 6px; color: var(--text); }
.form-group input, .form-group textarea, .form-group select {
    width: 100%;
    padding: 10px 14px;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    font-size: 14px;
    font-family: inherit;
    transition: var(--transition);
}
.form-group input:focus, .form-group textarea:focus, .form-group select:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(0,114,188,0.1);
}
.form-group textarea { resize: vertical; min-height: 100px; }

/* ===== Timeline ===== */
.timeline { position: relative; padding: 20px 0; }
.timeline::before {
    content: '';
    position: absolute;
    left: 50%;
    top: 0;
    bottom: 0;
    width: 2px;
    background: var(--border);
    transform: translateX(-50%);
}
.timeline-item {
    display: grid;
    grid-template-columns: 1fr 50px 1fr;
    gap: 20px;
    margin-bottom: 40px;
    align-items: center;
}
.timeline-item .tl-content {
    background: #fff;
    border-radius: var(--radius);
    padding: 20px 24px;
    box-shadow: var(--shadow);
}
.timeline-item .tl-content h4 { font-size: 16px; font-weight: 600; color: var(--primary); margin-bottom: 6px; }
.timeline-item .tl-content p { font-size: 14px; color: var(--text-light); }
.timeline-item .tl-dot {
    width: 16px;
    height: 16px;
    border-radius: 50%;
    background: var(--primary);
    margin: 0 auto;
    border: 4px solid var(--primary-light);
    z-index: 1;
}
.timeline-item .tl-year {
    text-align: center;
    font-size: 22px;
    font-weight: 700;
    color: var(--primary);
}

/* ===== Footer ===== */
.footer {
    background: #1a2b3c;
    color: #b0c4d6;
    padding: 60px 0 0;
}
.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 40px;
    margin-bottom: 40px;
}
.footer-brand .logo-text .cn { color: #fff; }
.footer-brand .logo-text .en { color: #6b8299; }
.footer-brand p { font-size: 14px; line-height: 1.8; margin-top: 16px; max-width: 300px; }
.footer-col h4 { font-size: 16px; color: #fff; margin-bottom: 16px; font-weight: 600; }
.footer-col ul li { margin-bottom: 10px; }
.footer-col ul li a { font-size: 14px; color: #b0c4d6; transition: var(--transition); }
.footer-col ul li a:hover { color: var(--accent); }
.footer-bottom {
    border-top: 1px solid #2a3b4c;
    padding: 20px 0;
    text-align: center;
    font-size: 13px;
    color: #6b8299;
}
.footer-bottom a { color: #b0c4d6; }

/* 页脚备案号 (ICP / 公安) */
.footer-beian {
    margin-top: 10px;
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 4px 20px;
    font-size: 12px;
    color: #6b8299;
}
.footer-beian a {
    color: #9db4c8;
    text-decoration: none;
    transition: var(--transition);
}
.footer-beian a:hover { color: var(--accent); }

/* ===== Animations ===== */
@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(30px); }
    to { opacity: 1; transform: translateY(0); }
}
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}
.fade-in.visible { opacity: 1; transform: translateY(0); }

/* ===== Responsive ===== */
@media (max-width: 1024px) {
    .domains-grid { grid-template-columns: repeat(3, 1fr); }
    .products-grid, .cases-grid { grid-template-columns: repeat(2, 1fr); }
    .cert-grid { grid-template-columns: 1fr; }
    .brand-story, .solution-item, .contact-grid { grid-template-columns: 1fr; gap: 30px; }
    .footer-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 768px) {
    .nav { display: none; }
    .menu-toggle { display: block; }
    .nav.open {
        display: flex;
        flex-direction: column;
        position: absolute;
        top: 72px;
        left: 0;
        right: 0;
        background: #fff;
        padding: 10px;
        box-shadow: var(--shadow-lg);
        gap: 0;
    }
    .nav.open a { padding: 12px 16px; border-radius: 0; width: 100%; }
    .nav.open .nav-dropdown { flex-direction: column; align-items: stretch; width: 100%; }
    .nav.open .nav-dropdown-menu {
        position: static;
        display: block;
        box-shadow: none;
        border: none;
        padding: 0 0 0 16px;
        min-width: 0;
    }
    .nav.open .nav-dropdown-menu a { padding: 10px 16px; font-size: 13px; }
    .hero h1 { font-size: 28px; }
    .hero .subtitle { font-size: 16px; }
    .section-header h2 { font-size: 24px; }
    .domains-grid { grid-template-columns: 1fr 1fr; }
    .products-grid, .cases-grid { grid-template-columns: 1fr; }
    .stats-grid { grid-template-columns: 1fr 1fr; gap: 20px; }
    .footer-grid { grid-template-columns: 1fr; }
    .timeline::before { left: 20px; }
    .timeline-item { grid-template-columns: 40px 1fr; }
    .timeline-item .tl-year { grid-column: 2; text-align: left; }
    .timeline-item .tl-content { grid-column: 2; }
    .timeline-item .tl-dot { grid-column: 1; }
    .news-item { flex-direction: column; }
    .news-date { width: 100%; display: flex; gap: 10px; justify-content: center; }
    .section { padding: 50px 0; }
}

/* ===== Banner 轮播器 ===== */
.hero-section {
    position: relative;
    overflow: hidden;
    height: 630px;
    background: #001f33;
}
.hero-track {
    display: flex;
    width: 100%;
    height: 100%;
    transition: transform 0.7s cubic-bezier(0.65, 0, 0.35, 1);
}
.hero-slide {
    flex: 0 0 100%;
    width: 100%;
    height: 100%;
    position: relative;
    display: flex;
    align-items: center;
    overflow: hidden;
}
/* 底图层：上传的图片/视频作为 banner 背景底图，整幅铺满（cover） */
.hero-bg {
    position: absolute;
    top: 0; right: 0; bottom: 0; left: 0;
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
}
.hero-bg::after {
    /* 爱士迪蓝色调遮罩：左侧深、右侧渐透，保证文字可读同时露出底图 */
    content: "";
    position: absolute;
    top: 0; right: 0; bottom: 0; left: 0;
    background: linear-gradient(100deg, rgba(0, 41, 70, 0.92) 0%, rgba(0, 61, 107, 0.72) 42%, rgba(0, 114, 188, 0.26) 72%, rgba(0, 61, 107, 0.10) 100%);
    pointer-events: none;
}
.hero-bg.hero-bg-video::after {
    /* 视频底图遮罩稍浅，保留画面质感 */
    background: linear-gradient(90deg, rgba(0, 41, 70, 0.74) 0%, rgba(0, 61, 107, 0.40) 45%, rgba(0, 41, 70, 0) 68%);
}
/* 背景视频铺满整屏 */
.hero-bg .hero-video-wrap {
    position: absolute;
    top: 0; right: 0; bottom: 0; left: 0;
}
.hero-bg .hero-video {
    width: 100%;
    height: 100%;
    max-height: none;
    object-fit: cover;
    border-radius: 0;
    background: transparent;
    box-shadow: none;
}
.hero-inner {
    position: relative;
    z-index: 2;
    max-width: 1200px;
    width: 100%;
    margin: 0 auto;
    padding: 60px 40px;
    display: flex;
    align-items: center;
    gap: 40px;
    color: #fff;
}
.hero-text {
    flex: 0 0 52%;
    max-width: 620px;
}
.hero-category {
    display: inline-block;
    padding: 5px 14px;
    background: rgba(78, 205, 196, 0.18);
    color: #4ECDC4;
    border: 1px solid rgba(78, 205, 196, 0.45);
    border-radius: 20px;
    font-size: 13px;
    letter-spacing: 1px;
    margin-bottom: 18px;
    font-weight: 500;
}
.hero-text h1 {
    font-size: 44px;
    line-height: 1.2;
    font-weight: 700;
    margin-bottom: 14px;
    text-shadow: 0 2px 18px rgba(0, 0, 0, 0.25);
}
.hero-subtitle {
    font-size: 22px;
    color: #4ECDC4;
    margin-bottom: 18px;
    font-weight: 500;
}
.hero-desc {
    font-size: 15px;
    line-height: 1.85;
    color: rgba(255, 255, 255, 0.85);
    margin-bottom: 28px;
    white-space: pre-line;
}
.hero-btns {
    display: flex;
    gap: 14px;
    flex-wrap: wrap;
}
/* ===== Banner 视频素材（背景视频模式） ===== */
.hero-video-wrap {
    position: relative;
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
}
.hero-video {
    display: block;
    width: 100%;
    max-height: 460px;
    object-fit: contain;
    border-radius: 10px;
    background: #000;
    box-shadow: 0 18px 40px rgba(0, 0, 0, 0.35);
    cursor: pointer;
}
.hero-video-fs,
.hero-video-sound {
    position: absolute;
    width: 36px;
    height: 36px;
    border: none;
    border-radius: 50%;
    background: rgba(0, 0, 0, 0.45);
    color: #fff;
    font-size: 16px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background 0.2s;
    z-index: 3;
}
.hero-video-fs:hover,
.hero-video-sound:hover {
    background: rgba(78, 205, 196, 0.75);
}
.hero-video-fs { right: 10px; top: 10px; }
.hero-video-sound { right: 54px; top: 10px; }
.hero-video-close {
    position: absolute;
    right: 16px;
    top: 16px;
    border: none;
    border-radius: 20px;
    background: rgba(255, 255, 255, 0.16);
    color: #fff;
    font-size: 14px;
    padding: 7px 16px;
    cursor: pointer;
    display: none;
    z-index: 3;
    backdrop-filter: blur(6px);
    transition: background 0.2s;
}
.hero-video-close:hover { background: rgba(255, 255, 255, 0.32); }
/* 全屏状态：黑底居中铺满 */
.hero-video-wrap:fullscreen {
    background: #000;
    width: 100%;
    height: 100%;
}
.hero-video-wrap:fullscreen .hero-video {
    width: auto;
    height: auto;
    max-width: 100%;
    max-height: 100vh;
    border-radius: 0;
    box-shadow: none;
}
.hero-video-wrap:fullscreen .hero-video-close { display: block; }
.hero-video-wrap:-webkit-full-screen { background: #000; }
.hero-video-wrap:-webkit-full-screen .hero-video {
    max-width: 100%;
    max-height: 100vh;
    border-radius: 0;
}
.hero-video-wrap:-webkit-full-screen .hero-video-close { display: block; }
.hero-arrow {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    width: 50px;
    height: 50px;
    border: none;
    background: rgba(255, 255, 255, 0.12);
    color: #fff;
    font-size: 28px;
    border-radius: 50%;
    cursor: pointer;
    z-index: 4;
    transition: background 0.25s, transform 0.25s;
    backdrop-filter: blur(6px);
}
.hero-arrow:hover {
    background: rgba(78, 205, 196, 0.5);
    transform: translateY(-50%) scale(1.08);
}
.hero-prev { left: 24px; }
.hero-next { right: 24px; }
.hero-dots {
    position: absolute;
    bottom: 22px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    gap: 10px;
    z-index: 4;
}
.hero-dot {
    width: 32px;
    height: 4px;
    border-radius: 2px;
    background: rgba(255, 255, 255, 0.4);
    border: none;
    cursor: pointer;
    padding: 0;
    transition: background 0.25s, width 0.25s;
}
.hero-dot.active {
    background: #4ECDC4;
    width: 48px;
}

/* Banner 响应式 */
@media (max-width: 900px) {
    .hero-section { height: 550px; }
    .hero-inner { padding: 40px 24px; gap: 20px; }
    .hero-text { flex: 1 1 100%; max-width: 100%; }
    .hero-text h1 { font-size: 30px; }
    .hero-subtitle { font-size: 18px; }
    .hero-bg::after {
        /* 移动端遮罩整体加深，保证小屏文字可读 */
        background: linear-gradient(180deg, rgba(0, 41, 70, 0.55) 0%, rgba(0, 41, 70, 0.72) 55%, rgba(0, 41, 70, 0.88) 100%);
    }
    .hero-bg.hero-bg-video::after {
        background: linear-gradient(180deg, rgba(0, 41, 70, 0.30) 0%, rgba(0, 41, 70, 0.62) 55%, rgba(0, 41, 70, 0.85) 100%);
    }
}
@media (max-width: 600px) {
    .hero-section { height: 550px; }
    .hero-text h1 { font-size: 24px; }
    .hero-arrow { width: 40px; height: 40px; font-size: 22px; }
}

/* ===== 资料下载列表 ===== */
.download-list {
    max-width: 860px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 16px;
}
.download-item {
    display: flex;
    align-items: center;
    gap: 18px;
    background: var(--white);
    border: 1px solid var(--border);
    border-radius: 14px;
    padding: 20px 24px;
    transition: all .25s;
}
.download-item:hover {
    box-shadow: var(--shadow);
    border-color: var(--accent);
    transform: translateY(-2px);
}
.download-item-icon {
    width: 56px;
    height: 56px;
    flex: 0 0 56px;
    border-radius: 12px;
    background: var(--primary-light);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 26px;
}
.download-item-main { flex: 1 1 auto; min-width: 0; }
.download-item-name {
    font-size: 17px;
    font-weight: 600;
    color: var(--text);
    margin-bottom: 6px;
    word-break: break-all;
}
.download-item-meta {
    font-size: 13px;
    color: var(--text-muted);
}
.download-item-btn { flex: 0 0 auto; white-space: nowrap; }
.download-empty {
    text-align: center;
    padding: 60px 0;
    color: var(--text-muted);
    background: var(--white);
    border: 1px dashed var(--border);
    border-radius: 14px;
}
@media (max-width: 600px) {
    .download-item { flex-wrap: wrap; gap: 12px; padding: 16px; }
    .download-item-btn { width: 100%; text-align: center; }
}