/* ============================================
   防止语言切换中文闪现
   ============================================ */
/* 默认可见（不阻塞首屏/LCP）；仅语言切换时由 i18n.js 临时隐藏做淡入过渡 */
body {
  opacity: 1;
}

/* ============================================
   图片防下载（前台所有页面生效）
   ============================================ */
img {
  -webkit-user-drag: none;
  user-select: none;
  -webkit-user-select: none;
  -moz-user-select: none;
  -ms-user-select: none;
}

/* ============================================
   鑫驰汽配 - 主样式文件
   ============================================ */

/* CSS 变量 */
:root {
    --primary: #c0392b;
    --primary-dark: #96281b;
    --primary-light: #e74c3c;
    --secondary: #1a3a6e;
    --secondary-dark: #0d2048;
    --secondary-light: #2c5282;
    --accent: #f39c12;
    --text-dark: #1a1a2e;
    --text-body: #444;
    --text-light: #777;
    --text-muted: #aaa;
    --bg-light: #f8f9fa;
    --bg-gray: #f0f2f5;
    --border: #e0e0e0;
    --white: #ffffff;
    --shadow-sm: 0 2px 8px rgba(0,0,0,0.08);
    --shadow-md: 0 8px 24px rgba(0,0,0,0.12);
    --shadow-lg: 0 16px 48px rgba(0,0,0,0.16);
    --radius-sm: 6px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --transition: all 0.3s ease;
    --font: 'Segoe UI', -apple-system, BlinkMacSystemFont, Roboto, 'Helvetica Neue', Arial, 'Microsoft YaHei', 'PingFang SC', sans-serif;
}

/* 基础重置 */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
/* ── Core Web Vitals: 触控响应与渲染优化 ── */
/* 消除移动端 ~300ms 点击延迟（无需 user-scalable=no，保留可访问性） */
html, body { touch-action: manipulation; }
/* 所有元素 box-sizing 统一，避免宽度计算导致横向溢出/布局偏移 */
*, *::before, *::after { box-sizing: border-box; }
/* 图片/视频默认避免溢出，配合 width/height 属性预留空间防 CLS */
img, video, iframe { max-width: 100%; height: auto; }
/* 首屏之外的区块延迟渲染（content-visibility），加速首屏；contain-intrinsic-size 预留高度防 CLS */
/* 注意：有锚点定位(#faqs/#certs/#fuel 等)的区块不使用，避免滚动定位时内容未渲染 */
.quick-nav, .about-section, .products-section, .advantages-section, .clients-section, .global-map-wrap,
.timeline-section, .factory-section, .news-section, .quality-system,
.contact-info-section, .contact-main-section, .fitment-section {
  content-visibility: auto;
  contain-intrinsic-size: auto 500px;
}
/* 内联区块（导航下拉、模态、轮播）不适用 content-visibility */
.hero-slider, .main-header, .top-bar, .modal-overlay, .dropdown-menu { content-visibility: visible; }
/* 图标渲染期间不闪烁 */
.fa, .fas, .far, .fab { -webkit-font-smoothing: antialiased; }

/* 屏幕阅读器专用：不可见但保留于语义结构 */
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0,0,0,0); white-space: nowrap; border: 0; }
body { font-family: var(--font); color: var(--text-body); background: var(--white); line-height: 1.7; overflow-x: hidden; }
a { text-decoration: none; color: inherit; transition: var(--transition); }
img { max-width: 100%; display: block; }
ul { list-style: none; }
button { cursor: pointer; border: none; background: none; font-family: var(--font); }
select { font-family: var(--font); }
/* 移动端触控优化：消除点击/双击缩放延迟，提升交互响应 */
a, button, input, select, textarea, .btn-card, .btn-primary, .btn-secondary, .quick-item, .tab-btn, .dot, .float-item {
  touch-action: manipulation;
}

/* 容器 */
.container { max-width: 1240px; margin: 0 auto; padding: 0 24px; }

/* ============================================
   顶部公告栏
   ============================================ */
.top-bar {
    background: var(--primary);
    color: rgba(255,255,255,0.85);
    font-size: 0.8rem;
    padding: 2px 0;
    border-bottom: 1px solid rgba(255,255,255,0.1);
}
.top-bar-content { display: flex; align-items: center; gap: 24px; }
.top-bar-content span { display: flex; align-items: center; gap: 6px; }
.top-bar-content i { color: var(--accent); font-size: 0.75rem; }
.top-bar-right { margin-left: auto; display: flex; align-items: center; gap: 10px; }
.top-bar-right a {
    width: 36px; height: 36px;
    background: rgba(255,255,255,0.08);
    border-radius: 50%;
    display: flex; align-items: center; justify-content: center;
    color: rgba(255,255,255,0.6); font-size: 0.9rem;
    transition: var(--transition);
}
.top-bar-right a:hover { background: var(--primary); color: white; }
.top-bar-right i { color: inherit; }
/* ============================================
   导航栏
   ============================================ */
.main-header {
    background: var(--white);
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 12px rgba(0,0,0,0.1);
    transition: var(--transition);
}
/* 锚点跳转时避开固定导航栏，防止标题被遮挡 */
[id] { scroll-margin-top: 80px; }
.main-header.scrolled { box-shadow: 0 4px 20px rgba(0,0,0,0.15); }

.navbar {
    display: flex;
    align-items: center;
    height: 72px;
    gap: 20px;
}

/* Logo */
.logo { display: flex; align-items: center; gap: 12px; flex-shrink: 0; }
.logo-icon {
    display: flex; align-items: center; justify-content: center;
    flex-shrink: 0;
}
.logo-icon img {
    max-width: none;
    height: 40px;
    width: auto;
}
.logo-text { display: flex; flex-direction: column; line-height: 1.2; }
.logo-cn { font-size: 1.2rem; font-weight: 700; color: var(--text-dark); letter-spacing: 1px; }
.logo-en { font-size: 0.58rem; font-weight: 500; color: var(--text-light); letter-spacing: 2px; text-transform: uppercase; }

/* 导航菜单 */
.nav-menu { display: flex; align-items: center; gap: 4px; margin-left: auto; }
.nav-menu > li { position: relative; }
.nav-menu > li > a {
    display: flex; align-items: center; gap: 4px;
    padding: 8px 14px;
    font-size: 0.92rem; font-weight: 500;
    color: var(--text-dark);
    border-radius: var(--radius-sm);
    white-space: nowrap;
}
.nav-menu > li > a:hover,
.nav-menu > li > a.active { color: var(--primary); }
.nav-menu > li > a.active { background: rgba(var(--primary-rgb),0.06); }
.nav-menu > li > a i { font-size: 0.65rem; transition: var(--transition); }
.nav-menu > li:hover > a i { transform: rotate(180deg); }

/* 下拉菜单 */
.has-dropdown { position: relative; }
.has-dropdown > .dropdown-toggle {
    display: flex; align-items: center; gap: 4px;
    padding: 8px 14px;
    font-size: 0.92rem; font-weight: 500;
    color: var(--text-dark);
    border-radius: var(--radius-sm);
    white-space: nowrap;
    cursor: pointer;
}
.has-dropdown > .dropdown-toggle:hover,
.has-dropdown > .dropdown-toggle.active { color: var(--primary); }
.has-dropdown > .dropdown-toggle i { font-size: 0.65rem; transition: var(--transition); }
.has-dropdown:hover > .dropdown-toggle i { transform: rotate(180deg); }

.dropdown-menu {
    position: absolute; top: 100%; left: 0;
    background: var(--white);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    box-shadow: var(--shadow-md);
    min-width: 180px;
    padding: 8px 0;
    opacity: 0; visibility: hidden;
    transform: translateY(8px);
    transition: var(--transition);
    z-index: 1001;
}
.has-dropdown:hover > .dropdown-menu,
.has-dropdown > .dropdown-menu.open,
.has-dropdown.open > .dropdown-menu {
    opacity: 1; visibility: visible; transform: translateY(0);
}
.dropdown-menu li { }
.dropdown-menu a {
    display: block;
    padding: 10px 20px;
    font-size: 0.88rem;
    color: var(--text-dark);
    white-space: nowrap;
    transition: var(--transition);
}
.dropdown-menu a:hover,
.dropdown-menu a.active {
    background: rgba(var(--primary-rgb),0.06);
    color: var(--primary);
}

/* 操作按钮 */
.nav-actions { display: flex; align-items: center; gap: 10px; flex-shrink: 0; }
.btn-search {
    width: 36px; height: 36px;
    border-radius: 50%;
    background: var(--bg-light);
    color: var(--text-body);
    font-size: 0.9rem;
    display: flex; align-items: center; justify-content: center;
    transition: var(--transition);
}
.btn-search:hover { background: var(--primary); color: white; }
.btn-quote {
    background: var(--primary);
    color: white;
    padding: 9px 20px;
    border-radius: 24px;
    font-size: 0.88rem;
    font-weight: 600;
    white-space: nowrap;
    transition: var(--transition);
}
.btn-quote:hover { background: var(--primary-dark); transform: translateY(-1px); box-shadow: 0 4px 12px rgba(var(--primary-rgb),0.35); }

/* 汉堡菜单 */
.hamburger { display: none; flex-direction: column; gap: 5px; padding: 4px; align-items: center; justify-content: center; }
.hamburger span { display: block; width: 24px; height: 2px; background: var(--text-dark); border-radius: 2px; transition: var(--transition); }
.hamburger.active span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.hamburger.active span:nth-child(2) { opacity: 0; }
.hamburger.active span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* 搜索覆盖层 */
.search-overlay {
    background: var(--secondary-dark);
    padding: 16px 0;
    display: none;
    border-top: 1px solid rgba(255,255,255,0.1);
}
.search-overlay.active { display: block; }
.search-box { display: flex; align-items: center; gap: 0; }
.search-box input {
    flex: 1; padding: 12px 20px;
    background: rgba(255,255,255,0.1); border: 1px solid rgba(255,255,255,0.2);
    border-right: none; border-radius: var(--radius-sm) 0 0 var(--radius-sm);
    color: white; font-size: 0.95rem; font-family: var(--font);
    outline: none;
}
.search-box input::placeholder { color: rgba(255,255,255,0.5); }
.search-box button {
    padding: 12px 24px;
    background: var(--primary); color: white;
    font-size: 0.9rem; font-weight: 500;
    border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
    transition: var(--transition);
}
.search-box button:hover { background: var(--primary-dark); }
.close-search { margin-left: 16px; color: rgba(255,255,255,0.6); cursor: pointer; font-size: 1.1rem; transition: var(--transition); }
.close-search:hover { color: white; }

/* ============================================
   Hero 轮播区
   ============================================ */
.hero-slider { position: relative; overflow: hidden; min-height: 580px; padding: 43px 0 0; }
.slide { position: absolute; inset: 0; opacity: 0; transition: opacity 0.7s ease; }
.slide.active { position: relative; opacity: 1; }
.slide-content { padding: 53px 0 60px; min-height: 580px; display: flex; align-items: center; position: relative; z-index: 1; }
.slide > img { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; z-index: 0; }
.slide-content .container { display: flex; align-items: center; width: 100%; }

.hero-text { flex: 1; max-width: 620px; }
.hero-badge {
    display: inline-block;
    background: rgba(255,255,255,0.12);
    border: 1px solid rgba(255,255,255,0.35);
    color: rgba(255,255,255,0.85);
    padding: 5px 14px; border-radius: 20px;
    font-size: 0.8rem; font-weight: 500;
    margin-bottom: 20px;
    letter-spacing: 0.5px;
}
.hero-text h1, .hero-text .hero-title { font-size: 2.4rem; font-weight: 900; color: white; line-height: 1.2; margin-bottom: 20px; }
.hero-text h1 .highlight, .hero-text .hero-title .highlight { font-size: 1.8rem; color: rgba(255,255,255,0.85); font-family: "Times New Roman", Times, serif; font-weight: 400; }
.hero-text p { font-size: 1.05rem; color: rgba(255,255,255,0.75); line-height: 1.8; margin-bottom: 32px; }

.hero-btns { display: flex; gap: 14px; flex-wrap: wrap; margin-bottom: 48px; }
.btn-primary {
    padding: 13px 30px; background: var(--primary); color: white;
    border-radius: 30px; font-weight: 600; font-size: 0.95rem;
    transition: var(--transition);
    box-shadow: 0 4px 16px rgba(var(--primary-rgb),0.4);
}
.btn-primary:hover { background: var(--primary-dark); transform: translateY(-2px); box-shadow: 0 8px 24px rgba(var(--primary-rgb),0.5); }
.btn-secondary {
    padding: 13px 30px; background: rgba(255,255,255,0.1); color: white;
    border: 1.5px solid rgba(255,255,255,0.4);
    border-radius: 30px; font-weight: 500; font-size: 0.95rem;
    transition: var(--transition);
    backdrop-filter: blur(8px);
}
.btn-secondary:hover { background: rgba(255,255,255,0.2); transform: translateY(-2px); }

.hero-stats { display: flex; gap: 32px; }
.stat { display: flex; flex-direction: column; gap: 2px; }
.stat strong { font-size: 1.8rem; font-weight: 800; color: white; line-height: 1; }
.stat span { font-size: 0.78rem; color: rgba(255,255,255,0.6); }

.hero-image { flex: 1; display: flex; justify-content: flex-end; }
.hero-img-wrapper { position: relative; width: 480px; height: 380px; }
.hero-img-wrapper img { width: 100%; height: 100%; object-fit: contain; }
.hero-floats { position: absolute; width: 100%; height: 100%; top: 0; left: 0; }
.float-card {
    position: absolute;
    background: rgba(255,255,255,0.12);
    backdrop-filter: blur(12px);
    border: 1px solid rgba(255,255,255,0.2);
    border-radius: var(--radius-sm);
    padding: 10px 16px;
    display: flex; align-items: center; gap: 8px;
    color: white; font-size: 0.85rem; font-weight: 500;
    animation: float 3s ease-in-out infinite;
}
.float-card i { color: var(--accent); }
.float-1 { top: 20%; left: -20px; animation-delay: 0s; }
.float-2 { bottom: 25%; right: -20px; animation-delay: 1.5s; }
@keyframes float { 0%, 100% { transform: translateY(0); } 50% { transform: translateY(-8px); } }

/* Hero 管路图形动画 */
.hero-pipes-visual {
    position: relative;
    width: 380px; height: 380px;
    display: flex; align-items: center; justify-content: center;
}
.pipe-ring {
    position: absolute; border-radius: 50%;
    border: 2px solid rgba(255,255,255,0.12);
    animation: rotatePipe 20s linear infinite;
}
.r1 { width: 380px; height: 380px; border-color: rgba(var(--primary-rgb),0.25); animation-duration: 25s; }
.r2 { width: 280px; height: 280px; border-color: rgba(255,255,255,0.15); border-style: dashed; animation-duration: 18s; animation-direction: reverse; }
.r3 { width: 180px; height: 180px; border-color: rgba(var(--primary-rgb),0.3); animation-duration: 12s; }
@keyframes rotatePipe { from { transform: rotate(0deg); } to { transform: rotate(360deg); } }

.pipe-center-icon {
    position: relative; z-index: 2;
    width: 100px; height: 100px;
    background: rgba(var(--primary-rgb),0.2);
    border: 2px solid rgba(var(--primary-rgb),0.5);
    border-radius: 50%;
    display: flex; align-items: center; justify-content: center;
    font-size: 2.8rem; color: rgba(255,255,255,0.8);
    backdrop-filter: blur(8px);
    box-shadow: 0 0 40px rgba(var(--primary-rgb),0.3);
}

.pipe-label {
    position: absolute;
    display: flex; align-items: center; gap: 6px;
    background: rgba(255,255,255,0.08);
    backdrop-filter: blur(8px);
    border: 1px solid rgba(255,255,255,0.15);
    color: rgba(255,255,255,0.85);
    padding: 7px 14px; border-radius: 20px;
    font-size: 0.82rem; font-weight: 500;
    white-space: nowrap;
}
.pipe-label i { color: var(--accent); }
.pl1 { top: 20px; left: 50%; transform: translateX(-50%); }
.pl2 { right: 10px; top: 50%; transform: translateY(-50%); }
.pl3 { bottom: 20px; left: 50%; transform: translateX(-50%); }
.pl4 { left: 10px; top: 50%; transform: translateY(-50%); }

/* 轮播控制 */
.slider-controls {
    position: absolute; bottom: 28px; left: 50%; transform: translateX(-50%);
    display: flex; align-items: center; gap: 16px; z-index: 10;
}
.slider-prev, .slider-next {
    width: 40px; height: 40px; border-radius: 50%;
    background: rgba(255,255,255,0.15); color: white;
    display: flex; align-items: center; justify-content: center;
    font-size: 0.85rem; backdrop-filter: blur(4px);
    border: 1px solid rgba(255,255,255,0.2);
    transition: var(--transition);
}
.slider-prev:hover, .slider-next:hover { background: var(--primary); border-color: var(--primary); }
.slider-dots { display: flex; gap: 8px; align-items: center; }
.dot {
    width: 8px; height: 8px; border-radius: 50%;
    background: rgba(255,255,255,0.4); cursor: pointer; transition: var(--transition);
}
.dot.active { background: var(--primary); width: 24px; border-radius: 4px; }

/* ============================================
   快速导航
   ============================================ */
.quick-nav { background: #ffffff; padding: 0; border-bottom: 1px solid var(--border); }
.quick-nav-grid { display: grid; grid-template-columns: repeat(5, 1fr); }
.quick-item {
    display: flex; align-items: center; gap: 14px;
    padding: 20px 24px;
    border-right: 1px solid var(--border);
    color: var(--text-body);
    transition: var(--transition);
    position: relative; overflow: hidden;
}
.quick-item:last-child { border-right: none; }
.quick-item::before {
    content: ''; position: absolute; inset: 0;
    background: var(--primary); transform: scaleX(0); transform-origin: left;
    transition: transform 0.3s ease;
}
.quick-item:hover::before { transform: scaleX(1); }
.quick-item:hover { color: white; }
.quick-icon {
    position: relative; z-index: 1; flex-shrink: 0;
    width: 48px; height: 48px; border-radius: 14px; overflow: hidden;
    display: flex; align-items: center; justify-content: center;
    font-size: 1.5rem; color: var(--accent);
}
.quick-icon img { max-width: 100%; max-height: 100%; object-fit: contain; }
.quick-icon i { font-size: 1.5rem; }
.quick-text { position: relative; z-index: 1; flex: 1; }
.quick-text h3 { font-size: 0.9rem; font-weight: 600; margin-bottom: 2px; }
.quick-text p { font-size: 0.72rem; opacity: 0.7; }
.quick-arrow { position: relative; z-index: 1; font-size: 0.75rem; opacity: 0; transition: var(--transition); }
.quick-item:hover .quick-arrow { opacity: 1; transform: translateX(4px); }

/* ============================================
   通用章节样式
   ============================================ */
section { padding: 64px 0; }
.section-header { text-align: center; margin-bottom: 40px; }
.section-tag {
    display: inline-block;
    background: rgba(var(--primary-rgb),0.1);
    color: var(--primary);
    padding: 4px 14px; border-radius: 20px;
    font-size: 0.8rem; font-weight: 600;
    margin-bottom: 12px; letter-spacing: 1px;
}
.section-header h2 { font-size: 2.2rem; font-weight: 800; color: var(--text-dark); margin-bottom: 12px; }
.section-header p { font-size: 1rem; color: var(--text-light); max-width: 580px; margin: 0 auto; }
.section-header.light h2 { color: white; }
.section-header.light p { color: rgba(255,255,255,0.65); }
.section-header.light .section-tag { background: rgba(255,255,255,0.15); color: rgba(255,255,255,0.9); }

/* ============================================
   关于我们
   ============================================ */
.about-section { background: var(--bg-light); }
.about-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; align-items: flex-start; }
.about-content .section-tag { display: inline-block; margin-bottom: 12px; }
.about-content h2 { font-size: 1.6rem; font-weight: 800; color: var(--text-dark); margin-bottom: 40px; line-height: 1.25; text-align: center; }
    .about-content h2#aboutIntroTitle { text-align: center; }
    .about-content .lead { font-size: 1rem; color: var(--text-body); margin-bottom: 14px; line-height: 1.7; }
    .about-content p { font-size: 0.92rem; color: var(--text-light); margin-bottom: 20px; line-height: 1.7; }
        .about-content #aboutIntroBody p { text-indent: 2em; }
    #aboutIntroBody { font-size: 0.92rem; color: var(--text-body); line-height: 1.8; margin-bottom: 40px; }
        #aboutIntroBody p { text-indent: 2em; margin-bottom: 14px; }
    .about-features { display: flex; flex-direction: column; gap: 10px; margin-bottom: 40px; }
.feature-item { display: flex; align-items: flex-start; gap: 10px; font-size: 0.9rem; color: var(--primary); }
.feature-item i { color: var(--primary); margin-top: 4px; flex-shrink: 0; }
.btn-outline {
    display: inline-flex; align-items: center; gap: 8px;
    padding: 11px 24px;
    border: 2px solid var(--primary);
    color: var(--primary);
    border-radius: 30px;
    font-weight: 600; font-size: 0.9rem;
    transition: var(--transition);
}
.btn-outline:hover { background: var(--primary); color: white; transform: translateY(-2px); }

.about-visual { position: relative; align-items: flex-start; }
    .visual-grid { display: grid; grid-template-columns: 1fr 1fr; grid-template-rows: 200px 200px auto; gap: 12px; border-radius: var(--radius-md); overflow: hidden; }
    .visual-item { border-radius: var(--radius-sm); overflow: hidden; }
    .v1 { grid-row: 1 / 3; }
    .v4 { grid-column: 1 / 3; grid-row: 3; aspect-ratio: 16 / 9; }
    .visual-placeholder { width: 100%; height: 100%; display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 10px; background: linear-gradient(135deg, #1a3a6e, #0d2048); color: rgba(255,255,255,0.6); font-size: 0.85rem; font-weight: 500; }
    .visual-placeholder.blue { background: linear-gradient(135deg, #0d2b4a, #1565c0); }
    .visual-placeholder.red { background: linear-gradient(135deg, var(--primary-dark), var(--primary)); }
    .visual-placeholder.green { background: linear-gradient(135deg, #0d3b2e, #1b5e20); }
    .visual-placeholder i { font-size: 2.5rem; opacity: 0.4; }
    .visual-item img { width: 100%; height: 100%; object-fit: cover; display: block; }

.about-badge-card {
    position: absolute; bottom: -20px; left: -20px;
    background: var(--primary);
    color: white; padding: 20px 28px;
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-md);
    text-align: center;
}
.badge-number { font-size: 2.5rem; font-weight: 900; line-height: 1; }
.badge-number sup { font-size: 1.2rem; }
.badge-text { font-size: 0.8rem; opacity: 0.9; }

/* ============================================
   产品展示
   ============================================ */
.products-section { background: var(--white); }
.products-tabs { display: flex; justify-content: center; gap: 8px; margin-bottom: 40px; flex-wrap: wrap; }
.tab-btn {
    padding: 10px 28px; border-radius: 30px;
    font-size: 0.9rem; font-weight: 500;
    color: var(--text-body); background: var(--bg-light);
    border: 1.5px solid var(--border);
    transition: var(--transition);
}
.tab-btn:hover { border-color: var(--primary); color: var(--primary); }
.tab-btn.active { background: var(--primary); color: white; border-color: var(--primary); }

.tab-content { display: none; }
.tab-content.active { display: block; }
.product-cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }

.product-card {
    background: var(--white);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    overflow: hidden;
    transition: var(--transition);
    position: relative;
}
.product-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-md); border-color: transparent; }

.product-img { position: relative; height: 200px; }
.product-img-placeholder {
    width: 100%; height: 100%;
    display: flex; flex-direction: column; align-items: center; justify-content: center;
    gap: 8px; font-size: 0.75rem; color: rgba(255,255,255,0.6);
}
.product-img-placeholder { background: linear-gradient(135deg, #1a3a6e, #0d2048); }
.product-img-placeholder.ac { background: linear-gradient(135deg, #0d2b4a, #1a6eb2); }
.product-img-placeholder.cool { background: linear-gradient(135deg, #0d3b2e, #1a7a5c); }
.product-img-placeholder.hyd { background: linear-gradient(135deg, #3d1f00, #8b4513); }
.product-img-placeholder i { font-size: 3.5rem; opacity: 0.4; }

.product-tag {
    position: absolute; top: 12px; right: 12px;
    background: var(--primary); color: white;
    font-size: 0.72rem; font-weight: 600;
    padding: 3px 10px; border-radius: 12px;
}
.product-tag.new-tag { background: var(--accent); }

.product-info { padding: 20px; }
.product-category { font-size: 0.76rem; color: var(--primary); font-weight: 600; margin-bottom: 6px; letter-spacing: 0.5px; }
.product-info h3 { font-size: 0.95rem; font-weight: 700; color: var(--text-dark); margin-bottom: 8px; line-height: 1.4; }
.product-info p { font-size: 0.82rem; color: var(--text-light); line-height: 1.6; margin-bottom: 14px; }
.product-specs { display: flex; gap: 10px; flex-wrap: wrap; margin-bottom: 16px; }
.product-specs span {
    display: flex; align-items: center; gap: 5px;
    font-size: 0.76rem; color: var(--text-muted);
    background: var(--bg-light); padding: 3px 10px; border-radius: 12px;
}
.product-specs i { color: var(--secondary); font-size: 0.72rem; }
.btn-card {
    display: block; text-align: center;
    padding: 9px 0;
    background: var(--bg-light); color: var(--secondary);
    border-radius: var(--radius-sm);
    font-size: 0.85rem; font-weight: 600;
    border: 1px solid var(--border);
    transition: var(--transition);
}
.btn-card:hover { background: var(--primary); color: white; border-color: var(--primary); }

.products-footer { text-align: center; margin-top: 40px; }

/* ============================================
   核心优势
   ============================================ */
.advantages-section { background: linear-gradient(135deg, var(--secondary-dark) 0%, #0d2048 100%); color: white; }
.advantages-section .section-tag { background: var(--primary-25, rgba(var(--primary-rgb),0.25)); color: var(--primary-light); }
.advantages-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }

.advantage-card {
    background: rgba(255,255,255,0.06);
    border: 1px solid rgba(255,255,255,0.1);
    border-radius: var(--radius-md);
    padding: 32px 28px;
    text-align: center;
    transition: var(--transition);
    position: relative; overflow: hidden;
}
.advantage-card::before {
    content: '';
    position: absolute; top: 0; left: 0; right: 0; height: 3px;
    background: linear-gradient(90deg, var(--primary), var(--accent));
    transform: scaleX(0); transition: var(--transition);
}
.advantage-card:hover { background: rgba(255,255,255,0.1); transform: translateY(-4px); }
.advantage-card:hover::before { transform: scaleX(1); }
.adv-icon {
    width: 64px; height: 64px;
    margin: 0 auto 20px;
    background: var(--primary-15, rgba(var(--primary-rgb),0.15));
    border-radius: 50%;
    display: flex; align-items: center; justify-content: center;
    font-size: 1.6rem; color: var(--accent);
    transition: var(--transition);
}
.advantage-card:hover .adv-icon { background: var(--primary); color: white; }
.advantage-card h3 { font-size: 0.7rem; font-weight: 700; margin-bottom: 12px; }
.advantage-card p { font-size: 0.45rem; color: rgba(255,255,255,0.45); line-height: 1.5; font-weight: 400; }
.adv-card {
    background: rgba(255,255,255,0.06);
    border: 1px solid rgba(255,255,255,0.1);
    border-radius: var(--radius-md);
    padding: 32px 28px;
    text-align: center;
    transition: var(--transition);
    position: relative; overflow: hidden;
}
.adv-card::before {
    content: '';
    position: absolute; top: 0; left: 0; right: 0; height: 3px;
    background: linear-gradient(90deg, var(--primary), var(--accent));
    transform: scaleX(0); transition: var(--transition);
}
.adv-card:hover { background: rgba(255,255,255,0.1); transform: translateY(-4px); }
.adv-card:hover::before { transform: scaleX(1); }
.adv-card h3 { font-size: 0.85rem; font-weight: 700; margin-bottom: 12px; color: white; }
.adv-card p { font-size: 0.6rem; color: rgba(255,255,255,0.45); line-height: 1.5; font-weight: 400; }

/* ============================================
   车型适配查询
   ============================================ */
.fitment-section { background: var(--bg-gray); padding: 56px 0; }
.fitment-card {
    background: white;
    border-radius: var(--radius-lg);
    padding: 48px;
    box-shadow: var(--shadow-md);
    display: flex; gap: 48px; align-items: center;
}
.fitment-text { flex: 0 0 320px; }
.fitment-text h2 { font-size: 1.6rem; font-weight: 800; color: var(--text-dark); margin-bottom: 10px; }
.fitment-text p { font-size: 0.9rem; color: var(--text-light); }
.fitment-form { flex: 1; }
.form-row { display: grid; grid-template-columns: 1fr 1fr 1fr auto; gap: 12px; margin-bottom: 12px; }
.form-row select {
    padding: 12px 16px;
    border: 1.5px solid var(--border);
    border-radius: var(--radius-sm);
    font-size: 0.9rem; color: var(--text-body);
    background: var(--bg-light);
    outline: none; cursor: pointer;
    transition: var(--transition);
    -webkit-appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 24 24' fill='%23777'%3E%3Cpath d='M7 10l5 5 5-5z'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 12px center;
    padding-right: 36px;
}
.form-row select:focus { border-color: var(--primary); background-color: white; }
.btn-search-fitment {
    padding: 12px 24px;
    background: var(--primary); color: white;
    border-radius: var(--radius-sm);
    font-size: 0.9rem; font-weight: 600;
    white-space: nowrap;
    transition: var(--transition);
}
.btn-search-fitment:hover { background: var(--primary-dark); transform: translateY(-1px); }
.fitment-hint { font-size: 0.82rem; color: var(--text-muted); }
.fitment-hint i { color: var(--secondary); }
.fitment-hint a { color: var(--primary); font-weight: 500; }
.fitment-hint a:hover { text-decoration: underline; }

/* ============================================
   荣誉资质
   ============================================ */
.certs-section { background: var(--bg-light); }
.certs-grid { display: grid; grid-template-columns: repeat(6, 1fr); gap: 20px; }
.cert-item {
    text-align: center; padding: 28px 16px;
    background: white; border-radius: var(--radius-md);
    border: 1px solid var(--border);
    transition: var(--transition);
}
.cert-item:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); border-color: var(--primary); }
.cert-icon { font-size: 2rem; color: var(--primary); margin-bottom: 12px; }
.cert-name { font-size: 0.88rem; font-weight: 700; color: var(--text-dark); margin-bottom: 6px; }
.cert-desc { font-size: 0.76rem; color: var(--text-light); }

/* ============================================
   合作客户滚动
   ============================================ */
.clients-section { overflow: hidden; background: white; }
.clients-track { overflow: hidden; padding: 20px 0; }
.clients-inner { display: flex; gap: 40px; animation: scrollClients 25s linear infinite; width: max-content; }
.clients-track:hover .clients-inner { animation-play-state: paused; }
@keyframes scrollClients {
    0% { transform: translateX(0); }
    100% { transform: translateX(-50%); }
}
.client-logo {
    display: flex; flex-direction: column; align-items: center; gap: 8px;
    min-width: 120px; padding: 20px 24px;
    background: var(--bg-light); border-radius: var(--radius-md);
    border: 1px solid var(--border); color: var(--text-light);
    font-size: 0.8rem; font-weight: 500;
    transition: var(--transition); flex-shrink: 0;
}
.client-logo i { font-size: 1.8rem; color: var(--text-muted); }
.client-logo:hover { border-color: var(--primary); color: var(--primary); }
.client-logo:hover i { color: var(--primary); }

/* ============================================
   洞察资讯
   ============================================ */
.news-section { background: var(--bg-gray); }
.news-grid { display: grid; grid-template-columns: 1.4fr 1fr 1fr; gap: 24px; }
.news-card { background: white; border-radius: var(--radius-md); overflow: hidden; transition: var(--transition); border: 1px solid var(--border); }
.news-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); border-color: transparent; }

.news-img { position: relative; }
.news-img-placeholder {
    height: 220px; background: linear-gradient(135deg, var(--secondary-dark), var(--secondary-light));
    display: flex; flex-direction: column; align-items: center; justify-content: center;
    gap: 10px; color: rgba(255,255,255,0.4); font-size: 0.8rem;
}
.news-img-placeholder i { font-size: 3rem; }
.news-card:not(.featured) .news-img-placeholder { height: 160px; }
.news-category {
    position: absolute; bottom: 14px; left: 14px;
    background: var(--primary); color: white;
    font-size: 0.72rem; font-weight: 600;
    padding: 3px 10px; border-radius: 12px;
}
.news-body { padding: 20px; }
.news-date { font-size: 0.78rem; color: var(--text-muted); margin-bottom: 10px; display: flex; align-items: center; gap: 6px; }
.news-body h3 { font-size: 0.95rem; font-weight: 700; color: var(--text-dark); margin-bottom: 10px; line-height: 1.5; }
.news-body p { font-size: 0.84rem; color: var(--text-light); line-height: 1.7; margin-bottom: 16px; display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }
.news-read-more { font-size: 0.84rem; color: var(--primary); font-weight: 600; display: flex; align-items: center; gap: 6px; transition: var(--transition); }
.news-read-more:hover { gap: 10px; }
.news-footer { text-align: center; margin-top: 36px; }

/* ============================================
   CTA 区块
   ============================================ */
.cta-section { padding: 56px 0; background: white; }
.cta-card {
    background: linear-gradient(135deg, var(--secondary-dark), var(--secondary));
    border-radius: var(--radius-lg); padding: 48px;
    display: flex; align-items: center; gap: 48px;
}
.cta-text { flex: 1; }
.cta-text h2 { font-size: 1.7rem; font-weight: 800; color: white; margin-bottom: 10px; }
.cta-text p { font-size: 0.95rem; color: rgba(255,255,255,0.7); }
.cta-actions { display: flex; gap: 16px; flex-shrink: 0; }
.cta-btn {
    display: flex; align-items: center; gap: 14px;
    padding: 16px 24px; border-radius: var(--radius-md);
    transition: var(--transition); min-width: 160px;
}
.cta-btn i { font-size: 1.4rem; flex-shrink: 0; }
.cta-btn div { display: flex; flex-direction: column; }
.cta-btn div span { font-size: 0.76rem; opacity: 0.8; }
.cta-btn div strong { font-size: 0.92rem; }
.cta-btn.phone { background: var(--primary); color: white; }
.cta-btn.phone:hover { background: var(--primary-dark); transform: translateY(-2px); }
.cta-btn.email { background: rgba(255,255,255,0.1); color: white; border: 1px solid rgba(255,255,255,0.2); }
.cta-btn.email:hover { background: rgba(255,255,255,0.18); transform: translateY(-2px); }
/* .cta-btn.wechat removed */

/* ============================================
   页脚
   ============================================ */
.main-footer { background: #0d1b2a; color: rgba(255,255,255,0.75); }
.footer-top { padding: 40px 0 28px; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1.5fr; gap: 40px; }

.footer-about .footer-logo { display: flex; align-items: center; gap: 12px; margin-bottom: 16px;background: transparent !important;  /* 加 !important 确保覆盖 */
 }
.footer-about .logo-icon {
    background: white;
    border-radius: 4px;
    padding: 4px;
}
.footer-about .logo-cn { color: white; }
.footer-about .logo-en { color: rgba(255,255,255,0.5); }
.footer-about .footer-slogan {
    display: block; font-size: 0.72rem; color: rgba(255,255,255,0.7);
    margin: 4px 0 0; line-height: 1.4; max-width: 240px;
}
/*.footer-about .logo-icon { background: linear-gradient(135deg, var(--primary), var(--primary-dark)); }*/
.footer-about p { font-size: 0.85rem; line-height: 1.8; color: rgba(255,255,255,0.55); margin-bottom: 20px; }
.footer-social { display: flex; gap: 10px; }
.footer-social a {
    width: 36px; height: 36px;
    background: rgba(255,255,255,0.08);
    border-radius: 50%;
    display: flex; align-items: center; justify-content: center;
    color: rgba(255,255,255,0.6); font-size: 0.9rem;
    transition: var(--transition);
}
.footer-social a:hover { background: var(--primary); color: white; }
.footer-social a[data-twitter] i { 
    color: #000 !important; 
    font-weight: 900; 
    opacity: 1;
    filter: drop-shadow(0 0 2px rgba(255,255,255,0.5));
}

.footer-col h2 { font-size: 0.95rem; font-weight: 700; color: white; margin-bottom: 20px; position: relative; padding-bottom: 10px; }
.footer-col h2::after { content: ''; position: absolute; bottom: 0; left: 0; width: 28px; height: 2px; background: var(--primary); }
.footer-col ul li { margin-bottom: 10px; }
.footer-col ul li a { font-size: 0.85rem; color: rgba(255,255,255,0.55); transition: var(--transition); }
.footer-col ul li a:hover { color: white; padding-left: 4px; }

.contact-list li { display: flex; gap: 10px; margin-bottom: 12px; align-items: flex-start; }
.contact-list i { color: var(--primary); font-size: 0.85rem; margin-top: 3px; flex-shrink: 0; }
.contact-list span { font-size: 0.85rem; color: rgba(255,255,255,0.55); }

.footer-bottom { border-top: 1px solid rgba(255,255,255,0.08); padding: 12px 0; }
.footer-bottom-content { display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 12px; }
.footer-bottom p { font-size: 0.82rem; color: rgba(255,255,255,0.4); }
.footer-links { display: flex; gap: 20px; align-items: center; }
.footer-links a { font-size: 0.82rem; color: rgba(255,255,255,0.4); transition: var(--transition); }
.footer-links a:hover { color: rgba(255,255,255,0.8); }
.footer-links span { font-size: 0.82rem; color: rgba(255,255,255,0.3); }

/* ============================================
   悬浮服务按钮
   ============================================ */
.float-service {
    position: fixed; right: 24px; bottom: 100px;
    display: flex; flex-direction: column; gap: 10px; z-index: 500;
}
.float-item {
    width: 48px; height: 48px;
    background: var(--secondary); color: white;
    border-radius: 50%; display: flex; align-items: center; justify-content: center;
    font-size: 1.1rem; cursor: pointer; transition: var(--transition);
    box-shadow: 0 4px 16px rgba(0,0,0,0.25);
    position: relative;
}
.float-item:hover { background: var(--primary); transform: scale(1.1); }
.float-item.quote-btn { background: var(--primary); }
.float-item.quote-btn:hover { background: var(--primary-dark); }

.float-tooltip {
    position: absolute; right: calc(100% + 12px); top: 50%; transform: translateY(-50%);
    background: #333; color: white; border-radius: var(--radius-sm); padding: 12px 16px;
    min-width: 130px; text-align: center; white-space: nowrap;
    opacity: 0; visibility: hidden; transition: var(--transition); pointer-events: none;
}
.float-tooltip::after {
    content: ''; position: absolute; left: 100%; top: 50%; transform: translateY(-50%);
    border: 6px solid transparent; border-left-color: #333;
}
.float-item:hover .float-tooltip, .float-item.active .float-tooltip { opacity: 1; visibility: visible; }
/* .qr-placeholder removed */
.float-tooltip span, .float-tooltip strong { display: block; font-size: 0.78rem; }
.phone-tip strong { font-size: 0.95rem; color: var(--accent); margin-bottom: 4px; }
.phone-tip span { font-size: 0.75rem; color: rgba(255,255,255,0.7); }

/* 回到顶部 */
.back-to-top {
    position: fixed; right: 24px; bottom: 40px;
    width: 44px; height: 44px; border-radius: 50%;
    background: var(--primary); color: white;
    display: flex; align-items: center; justify-content: center;
    font-size: 0.9rem; box-shadow: 0 4px 16px rgba(var(--primary-rgb),0.4);
    opacity: 0; visibility: hidden; transform: translateY(10px);
    transition: var(--transition); z-index: 500;
}
.back-to-top.visible { opacity: 1; visibility: visible; transform: translateY(0); }
.back-to-top:hover { background: var(--primary-dark); transform: translateY(-2px); }

/* ============================================
   动画
   ============================================ */
[data-aos] { opacity: 0; transform: translateY(24px); transition: opacity 0.6s ease, transform 0.6s ease; }
[data-aos].visible { opacity: 1; transform: translateY(0); }

/* ============================================
   响应式设计
   ============================================ */
@media (max-width: 1100px) {
    .hero-text h1, .hero-text .hero-title { font-size: 2.4rem; }
    .hero-image { display: none; }
    .certs-grid { grid-template-columns: repeat(3, 1fr); }
    .news-grid { grid-template-columns: 1fr; }
    .news-card.featured .news-img-placeholder { height: 220px; }
    .product-cards { grid-template-columns: repeat(3, 1fr); }
    .footer-grid { grid-template-columns: 1fr 1fr; gap: 32px; }
}

@media (max-width: 900px) {
    html { font-size: 15px; }
    .top-bar { display: none; }
    .quick-nav { display: none; }
    .hamburger { display: flex; flex-shrink: 0; }
    .navbar { gap: 12px; }
    .logo { gap: 8px; min-width: 0; }
    .logo-icon img { height: 32px; }
    .logo-text { min-width: 0; }
    .logo-cn { font-size: 0.95rem; letter-spacing: 0; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
    .logo-en { display: none; }
    .nav-actions { gap: 6px; }
    .nav-menu {
        position: fixed; top: 72px; left: 0; right: 0;
        background: white; flex-direction: column; gap: 0;
        padding: 16px 0; box-shadow: var(--shadow-md);
        transform: translateY(-110%); opacity: 0; pointer-events: none;
        transition: var(--transition); z-index: 999; max-height: 80vh; overflow-y: auto;
    }
    .nav-menu.open { transform: translateY(0); opacity: 1; pointer-events: all; }
    .nav-menu > li { width: 100%; }
    .nav-menu > li > a { padding: 16px 24px; border-radius: 0; border-bottom: 1px solid var(--bg-light); min-height: 48px; display: flex; align-items: center; }
    /* 手机端隐藏下拉框：点击 Insights 直接跳转看全部文章 */
    .has-dropdown > .dropdown-menu,
    .has-dropdown.open > .dropdown-menu { display: none !important; }
    .has-dropdown.open > .dropdown-menu a {
        display: none;
    }
    .has-dropdown.open > .dropdown-toggle i { transform: none; }

    .about-grid { grid-template-columns: 1fr; }
    .about-visual { display: none; }
    .advantages-grid { grid-template-columns: repeat(3, 1fr); }
    .fitment-card { flex-direction: column; }
    .form-row { grid-template-columns: 1fr 1fr; }
    .quick-nav-grid { grid-template-columns: repeat(3, 1fr); }
    .quick-item:nth-child(4) { border-top: 1px solid var(--border); }
    .quick-item:nth-child(3) { border-right: none; }
    .cta-card { flex-direction: column; }
    .cta-actions { flex-wrap: wrap; }
    .clients-section .section-header { margin-bottom: 32px; }
}

@media (max-width: 640px) {
    html { font-size: 14px; }
    section { padding: 56px 0; }
    .hero-text h1, .hero-text .hero-title { font-size: 1.6rem; }
    .hero-stats { gap: 20px; flex-wrap: wrap; }
    .stat strong { font-size: 1.4rem; }
    .section-header h2 { font-size: 1.3rem; white-space: normal; }
    .section-header p { white-space: normal !important; font-size: 0.85rem; }
    .product-cards { grid-template-columns: 1fr; }
    .advantages-grid { grid-template-columns: 1fr; }
    .certs-grid { grid-template-columns: repeat(2, 1fr); }
    .quick-nav-grid { grid-template-columns: repeat(2, 1fr); }
    .quick-item:nth-child(odd) { border-right: 1px solid var(--border); }
    .quick-item:nth-child(n+3) { border-top: 1px solid var(--border); }
    .quick-item:nth-child(3) { border-right: 1px solid var(--border); }
    .quick-item:nth-child(4) { border-top: 1px solid var(--border); border-right: none; }
    .quick-item:last-child { border-right: none; }
    .hero-stats { gap: 20px; flex-wrap: wrap; }
    .slider-prev, .slider-next { display: none; }
    .adv-icon { display: none; }
    .products-tabs { flex-wrap: nowrap; gap: 4px; }
    .tab-btn { flex: 1; min-width: 0; min-height: 40px; padding: 8px 3px; font-size: 0.62rem; white-space: nowrap; }
    .form-row { grid-template-columns: 1fr; }
    .footer-grid { grid-template-columns: 1fr; }
    /* 移动端只保留公司介绍列（第1列）；隐藏 Products/About Us/Contact */
    .footer-grid .footer-col:nth-child(2),
    .footer-grid .footer-col:nth-child(3),
    .footer-grid .footer-col:nth-child(4) { display: none; }
    .footer-bottom-content { flex-direction: column; text-align: center; }
    .fitment-text { flex: none; }
    .cta-card { padding: 28px 20px; }
    .hero-slider { min-height: 0; padding: 0; }
    #heroSlides { min-height: 0 !important; }
    .slide-content { padding: 32px 0 36px; min-height: 300px; }
    .hero-text p { margin-bottom: 20px; line-height: 1.6; }
    /* ── 移动端触摸目标 ≥48px（Google 移动易用性标准） ── */
    .footer-social a { width: 48px; height: 48px; }
    .dot { width: 14px; height: 14px; }
    .dot.active { width: 28px; }
    .back-to-top { width: 48px; height: 48px; }
    .hamburger { min-width: 48px; min-height: 48px; }
    .hero-btns { gap: 10px; flex-direction: row; }
    .hero-btns .btn-primary, .hero-btns .btn-secondary { padding: 11px 18px; font-size: 0.88rem; width: auto; min-height: 48px; display: inline-flex; align-items: center; justify-content: center; flex: 1; white-space: nowrap; }
    .btn-quote { padding: 10px 14px; font-size: 0.82rem; min-height: 48px; display: inline-flex; align-items: center; justify-content: center; }
}

@media (max-width: 365px) {
    html { font-size: 13px; }
    .navbar { gap: 8px; }
    .logo { gap: 6px; }
    .logo-icon img { height: 26px; }
    .logo-cn { font-size: 0.82rem; max-width: 42vw; }
    .nav-actions .btn-quote { padding: 10px 14px; font-size: 0.82rem; min-height: 48px; }
    .hamburger { padding: 12px 10px; }
    .hamburger span { width: 20px; }
}