/* ============================================
   Uniarms Instruments - Global Stylesheet
   ============================================ */

/* ---------- CSS Variables ---------- */
:root {
  --primary: #009893;
  --primary-dark: #007a76;
  --primary-light: #e6f5f5;
  --primary-rgb: 0,152,147;
  --accent: #f7941d;
  --accent-dark: #d4780a;
  --text: #333;
  --text-light: #666;
  --text-muted: #999;
  --bg: #fff;
  --bg-light: #f7f9fc;
  --bg-dark: #1a2a3a;
  --border: #e0e6ed;
  --shadow: 0 2px 12px rgba(0,0,0,.08);
  --shadow-lg: 0 8px 32px rgba(0,0,0,.12);
  --radius: 8px;
  --radius-sm: 4px;
  --transition: .3s ease;
  --max-width: 1200px;
  --header-height: 72px;
}

/* ---------- Reset ---------- */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: 'Segoe UI', 'Helvetica Neue', Arial, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}
a { color: var(--primary); text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--primary-dark); }
img { max-width: 100%; height: auto; display: block; }
ul, ol { list-style: none; }
button { cursor: pointer; border: none; background: none; font: inherit; }
input, textarea, select { font: inherit; }

/* ---------- Utility ---------- */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}
.section-title {
  font-size: 2rem;
  font-weight: 700;
  text-align: center;
  margin-bottom: 12px;
  color: var(--primary-dark);
}
.section-subtitle {
  text-align: center;
  color: var(--text-light);
  font-size: 1.05rem;
  max-width: 640px;
  margin: 0 auto 48px;
}
.section { padding: 80px 0; }
.btn {
  display: inline-block;
  padding: 12px 32px;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: .95rem;
  letter-spacing: .3px;
  transition: all var(--transition);
  text-align: center;
}
.btn-primary {
  background: var(--primary);
  color: #fff;
}
.btn-primary:hover {
  background: var(--primary-dark);
  color: #fff;
  transform: translateY(-1px);
  box-shadow: 0 4px 16px rgba(var(--primary-rgb),.3);
}
.btn-accent {
  background: var(--accent);
  color: #fff;
}
.btn-accent:hover {
  background: var(--accent-dark);
  color: #fff;
  transform: translateY(-1px);
  box-shadow: 0 4px 16px rgba(247,148,29,.3);
}
.btn-outline {
  border: 2px solid var(--primary);
  color: var(--primary);
  background: transparent;
}
.btn-outline:hover {
  background: var(--primary);
  color: #fff;
}
.btn-white {
  background: #fff;
  color: var(--primary-dark);
  font-weight: 600;
}
.btn-white:hover {
  background: #f0f0f0;
  color: var(--primary-dark);
  transform: translateY(-1px);
}

/* ============================================
   HEADER / NAVIGATION (Transparent overlay)
   ============================================ */
.header {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: var(--header-height);
  background: rgba(0,0,0,.35);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  z-index: 1000;
  transition: all var(--transition);
}
.header.scrolled {
  position: fixed;
  top: 0;
  background: #2a2a2a;
  box-shadow: 0 2px 8px rgba(0,0,0,.15);
}
.header.scrolled .logo { color: #fff; }
.header.scrolled .logo-icon { background: rgba(255,255,255,.2); }
.header.scrolled .nav-list a { color: rgba(255,255,255,.8); }
.header.scrolled .nav-list a:hover,
.header.scrolled .nav-list a.active { color: #fff; background: rgba(255,255,255,.15); }
.header.scrolled .nav-toggle span { background: #fff; }
/* 内页导航栏：固定定位+深色背景 */
.header.header-dark {
  position: fixed;
  background: #2a2a2a;
  box-shadow: 0 2px 8px rgba(0,0,0,.15);
}
.header.header-dark .logo { color: #fff; }
.header.header-dark .nav-list a { color: rgba(255,255,255,.8); }
.header.header-dark .nav-list a:hover,
.header.header-dark .nav-list a.active { color: #fff; background: rgba(255,255,255,.15); }
.header.header-dark .nav-toggle span { background: #fff; }
.header.header-dark .logo-icon { background: rgba(255,255,255,.2); }
.header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}
.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.3rem;
  font-weight: 700;
  color: #fff;
  text-decoration: none;
  transition: color var(--transition);
}
.header.scrolled .logo { color: var(--primary-dark); }
.logo img {
  height: 36px;
  width: auto;
}
.logo-icon {
  width: 40px;
  height: 40px;
  background: rgba(255,255,255,.2);
  border-radius: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-weight: 800;
  font-size: 1.1rem;
  transition: background var(--transition);
}
.header.scrolled .logo-icon { background: var(--primary); }
.nav-list {
  display: flex;
  align-items: center;
  gap: 4px;
}
.nav-list a {
  display: block;
  padding: 8px 18px;
  font-size: .93rem;
  font-weight: 500;
  color: rgba(255,255,255,.9);
  border-radius: var(--radius-sm);
  transition: all var(--transition);
}
.nav-list a:hover,
.nav-list a.active {
  color: #fff;
  background: rgba(255,255,255,.2);
}
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 4px;
}
.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: #fff;
  border-radius: 2px;
  transition: all var(--transition);
}
.header.scrolled .nav-toggle span { background: var(--text); }

/* ============================================
   HERO SLIDER (Homepage)
   ============================================ */
.hero-slider {
  position: relative;
  width: 100%;
  height: 600px;
  overflow: hidden;
}
.hero-slide {
  position: absolute;
  inset: 0;
  opacity: 0;
  transition: opacity .8s ease;
  display: flex;
  align-items: center;
  justify-content: center;
}
.hero-slide.active { opacity: 1; }
.hero-slide-bg {
  position: absolute;
  inset: 0;
  background-size: cover;
  background-position: center;
  filter: brightness(.45);
}
.hero-slide-content {
  position: relative;
  z-index: 2;
  text-align: center;
  color: #fff;
  max-width: 700px;
  padding: 0 24px;
}
.hero-slide-content h1 {
  font-size: 2.8rem;
  font-weight: 800;
  line-height: 1.25;
  margin-bottom: 16px;
  text-shadow: 0 2px 8px rgba(0,0,0,.3);
}
.hero-slide-content h1 span { color: var(--accent); }
.hero-slide-content p {
  font-size: 1.15rem;
  line-height: 1.7;
  opacity: .9;
  margin-bottom: 28px;
}
.hero-slide-color {
  position: absolute;
  inset: 0;
}
.hero-slide-color.bg-1 {
  background: linear-gradient(135deg, #007a76 0%, #009893 40%, #00b5af 100%);
}
.hero-slide-color.bg-2 {
  background: linear-gradient(135deg, #003d3c 0%, #006b67 50%, #009893 100%);
}
.hero-slide-color.bg-3 {
  background: linear-gradient(135deg, #009893 0%, #006b67 40%, #004d4a 100%);
}

/* Slider Controls */
.slider-dots {
  position: absolute;
  bottom: 28px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 10;
  display: flex;
  gap: 10px;
}
.slider-dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: rgba(255,255,255,.4);
  cursor: pointer;
  transition: all var(--transition);
  border: 2px solid transparent;
}
.slider-dot.active {
  background: #fff;
  transform: scale(1.2);
}
.slider-arrows {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  z-index: 10;
  width: 100%;
  display: flex;
  justify-content: space-between;
  padding: 0 20px;
  pointer-events: none;
}
.slider-arrow {
  width: 48px;
  height: 48px;
  background: rgba(255,255,255,.15);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 1.4rem;
  cursor: pointer;
  pointer-events: auto;
  transition: all var(--transition);
  backdrop-filter: blur(4px);
}
.slider-arrow:hover {
  background: rgba(255,255,255,.3);
  transform: scale(1.1);
}

/* ============================================
   FEATURES SECTION
   ============================================ */
.features {
  background: var(--bg);
}
.features-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 32px;
}
.feature-card {
  background: var(--bg-light);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 36px 28px;
  text-align: center;
  transition: all var(--transition);
}
.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--primary);
}
.feature-icon {
  width: 64px;
  height: 64px;
  margin: 0 auto 20px;
  background: var(--primary);
  color: #fff;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.6rem;
}
.feature-card h3 {
  font-size: 1.15rem;
  margin-bottom: 12px;
  color: var(--primary-dark);
}
.feature-card p {
  font-size: .92rem;
  color: var(--text-light);
  line-height: 1.7;
}

/* ============================================
   PRODUCTS SECTION
   ============================================ */
.products {
  background: var(--bg-light);
}
.products-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 32px;
}
.product-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  transition: all var(--transition);
}
.product-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}
.product-image {
  width: 100%;
  height: 220px;
  background: var(--primary-light);
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  border-bottom: 1px solid var(--border);
}
.product-image img {
  max-width: 100%;
  max-height: 200px;
  object-fit: contain;
  transition: transform var(--transition);
}
.product-card:hover .product-image img { transform: scale(1.05); }
.product-info {
  padding: 24px;
}
.product-info h3 {
  font-size: 1.15rem;
  color: var(--primary-dark);
  margin-bottom: 8px;
}
.product-info p {
  display: none;
}
.product-info .btn {
  width: 100%;
  padding: 10px 20px;
  font-size: .88rem;
}

/* ============================================
   ABOUT SECTION (Homepage)
   ============================================ */
.about {
  background: var(--bg);
}
.about .container {
  /* 不设 grid，由 about-overview 内部控制两栏布局 */
}
.about-image {
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
}
.about-image img {
  width: 100%;
  height: 320px;
  object-fit: cover;
}
.about-content h2 {
  font-size: 1.8rem;
  color: var(--primary-dark);
  margin-bottom: 20px;
  text-align: center;
}
.about .section-subtitle {
  display: none;
}
.about-content p {
  color: var(--text-light);
  line-height: 1.8;
  margin-bottom: 16px;
}
.about-stats {
  display: flex;
  justify-content: center;
  margin-top: 28px;
}
.about-stats a.btn {
  display: inline-block;
}

/* ============================================
   CTA SECTION
   ============================================ */
.cta-section {
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
  color: #fff;
  text-align: center;
  padding: 80px 0;
}
.cta-section h2 {
  font-size: 2rem;
  margin-bottom: 16px;
}
.cta-section p {
  font-size: 1.1rem;
  opacity: .9;
  margin-bottom: 32px;
  max-width: 560px;
  margin-left: auto;
  margin-right: auto;
}
.cta-section .btn-accent {
  font-size: 1.05rem;
  padding: 14px 40px;
}

/* ============================================
   FOOTER
   ============================================ */
.footer {
  background: var(--primary-dark);
  color: rgba(255,255,255,.85);
  padding: 60px 0 0;
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1.2fr;
  gap: 40px;
  padding-bottom: 40px;
  border-bottom: 1px solid rgba(255,255,255,.1);
}
.footer h4 {
  color: #fff;
  font-size: 1rem;
  margin-bottom: 20px;
  position: relative;
  padding-bottom: 10px;
}
.footer h4::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 36px;
  height: 2px;
  background: var(--accent);
}
.footer-about p {
  font-size: .9rem;
  line-height: 1.7;
  margin-bottom: 16px;
}
.footer-links li { margin-bottom: 10px; }
.footer-links a {
  color: rgba(255,255,255,.7);
  font-size: .9rem;
  transition: all var(--transition);
}
.footer-links a:hover {
  color: var(--accent);
  padding-left: 4px;
}
.footer-contact li {
  display: flex;
  gap: 12px;
  margin-bottom: 14px;
  font-size: .9rem;
}
.footer-contact .icon {
  color: var(--accent);
  flex-shrink: 0;
  margin-top: 3px;
}
.footer-bottom {
  text-align: center;
  padding: 20px 0;
  font-size: .85rem;
  color: rgba(255,255,255,.5);
}

/* ============================================
   PRODUCT LIST PAGE
   ============================================ */
.product-list-page {
  margin-top: var(--header-height);
}
.product-list-hero {
  background: linear-gradient(135deg, #005a58 0%, #007a76 100%);
  color: #fff;
  padding: 60px 0 48px;
  text-align: center;
}
.product-list-hero h1 { font-size: 2.2rem; margin-bottom: 12px; }
.product-list-hero p { font-size: 1.05rem; opacity: .85; }
.product-list-body { padding: 60px 0; }
.product-filter {
  display: flex;
  gap: 12px;
  justify-content: center;
  margin-bottom: 40px;
}
.filter-btn {
  padding: 10px 24px;
  border: 2px solid var(--primary);
  border-radius: var(--radius-sm);
  background: transparent;
  color: var(--primary);
  font-weight: 600;
  font-size: .9rem;
  cursor: pointer;
  transition: all var(--transition);
}
.filter-btn:hover, .filter-btn.active {
  background: var(--primary);
  color: #fff;
}
.product-list-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 40px;
}
.product-list-item {
  background: var(--bg-light);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  transition: all var(--transition);
}
.product-list-item:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--primary);
}
.product-list-item .product-image {
  height: 240px;
  background: linear-gradient(135deg, var(--primary-light), #fff);
}
.product-list-item .product-info {
  padding: 28px;
}
.product-list-item .product-info h3 {
  font-size: 1.2rem;
  color: var(--primary-dark);
  margin-bottom: 8px;
}
.product-list-item .product-info p {
  display: none;
}

/* ============================================
   PRODUCT DETAIL PAGE
   ============================================ */
.product-detail {
  margin-top: var(--header-height);
  padding: 48px 0;
}
.breadcrumb {
  margin-bottom: 32px;
  font-size: .88rem;
  color: var(--text-muted);
}
.breadcrumb a { color: var(--text-light); }
.breadcrumb span { margin: 0 8px; color: var(--text-muted); }
.breadcrumb .current { color: var(--primary); }
.product-detail-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: start;
}
.product-gallery {
  background: var(--bg-light);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px;
  text-align: center;
}
.product-gallery .main-image {
  width: 100%;
  max-height: 360px;
  object-fit: contain;
  margin-bottom: 20px;
}
.product-gallery .thumb-list {
  display: flex;
  gap: 10px;
  justify-content: center;
}
.product-gallery .thumb {
  width: 64px;
  height: 64px;
  border: 2px solid var(--border);
  border-radius: var(--radius-sm);
  cursor: pointer;
  object-fit: contain;
  transition: border-color var(--transition);
  background: var(--primary-light);
}
.product-gallery .thumb:hover,
.product-gallery .thumb.active { border-color: var(--primary); }
.product-summary h1 {
  font-size: 1.8rem;
  color: var(--primary-dark);
  margin-bottom: 8px;
}
.product-summary .model-tag {
  display: inline-block;
  background: var(--primary-light);
  color: var(--primary);
  padding: 4px 14px;
  border-radius: 20px;
  font-size: .82rem;
  font-weight: 600;
  margin-bottom: 16px;
}
.product-summary .short-desc {
  color: var(--text-light);
  line-height: 1.8;
  margin-bottom: 24px;
}
.product-summary .btn-primary { margin-bottom: 28px; }

/* Product Tabs - Removed for simplified layout */

/* Specs Table */
.specs-table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: 24px;
}
.specs-table tr:nth-child(even) { background: var(--bg-light); }
.specs-table td {
  padding: 14px 18px;
  border-bottom: 1px solid var(--border);
  font-size: .93rem;
}
.specs-table td:first-child {
  font-weight: 600;
  color: var(--primary-dark);
  width: 200px;
}
.specs-table td:last-child { color: var(--text-light); }

/* Features List */
.features-list {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}
.features-list li {
  display: flex;
  gap: 12px;
  align-items: flex-start;
  font-size: .93rem;
  color: var(--text-light);
  line-height: 1.6;
}
.features-list li::before {
  content: '\2713';
  color: var(--primary);
  font-weight: 700;
  flex-shrink: 0;
  margin-top: 2px;
}

/* ============================================
   GENERIC CONTENT PAGE (About / Download)
   ============================================ */
.content-page {
  margin-top: var(--header-height);
}
.page-hero {
  background: linear-gradient(135deg, #005a58 0%, #007a76 100%);
  color: #fff;
  padding: 60px 0 48px;
  text-align: center;
}
.page-hero h1 { font-size: 2.2rem; margin-bottom: 12px; }
.page-hero p { font-size: 1.05rem; opacity: .85; }
.content-body { padding: 60px 0; }
.content-body h2 {
  font-size: 1.5rem;
  color: var(--primary-dark);
  margin: 32px 0 16px;
}
.content-body h2:first-child { margin-top: 0; }
.content-body p {
  color: var(--text-light);
  line-height: 1.8;
  margin-bottom: 16px;
}
.content-body img {
  border-radius: var(--radius);
  margin: 24px 0;
  box-shadow: var(--shadow);
}

/* About Page - Three Column Cards */
.about-cards-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 40px;
  margin-top: 48px;
}
.about-card {
  text-align: center;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  transition: all var(--transition);
}
.about-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--primary);
}
.about-card-image {
  width: 100%;
  height: 240px;
  overflow: hidden;
}
.about-card-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform var(--transition);
}
.about-card:hover .about-card-image img { transform: scale(1.05); }
.about-card-content {
  padding: 28px;
}
.about-card-content h3 {
  font-size: 1.15rem;
  color: var(--primary-dark);
  margin-bottom: 12px;
}
.about-card-content p {
  font-size: .9rem;
  color: var(--text-light);
  line-height: 1.7;
}

/* Company Overview - Image + Text */
.about-overview {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: center;
  margin-bottom: 48px;
}
.about-overview img {
  width: 100%;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

/* ============================================
   CONTACT FORM & MAP
   ============================================ */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
}
.contact-info-card {
  display: flex;
  gap: 16px;
  margin-bottom: 24px;
  padding: 20px;
  background: var(--bg-light);
  border-radius: var(--radius);
  border: 1px solid var(--border);
}
.contact-info-card .icon {
  width: 48px;
  height: 48px;
  background: var(--primary);
  color: #fff;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  flex-shrink: 0;
}
.contact-info-card h4 {
  font-size: .95rem;
  color: var(--primary-dark);
  margin-bottom: 4px;
}
.contact-info-card p {
  font-size: .88rem;
  color: var(--text-light);
}
.contact-form {
  background: var(--bg-light);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 36px;
}
.form-group { margin-bottom: 20px; }
.form-group label {
  display: block;
  font-size: .9rem;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 6px;
}
.form-group input,
.form-group select,
.form-group textarea {
  width: 100%;
  padding: 12px 16px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: .93rem;
  color: var(--text);
  background: var(--bg);
  transition: border-color var(--transition), box-shadow var(--transition);
}
.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(var(--primary-rgb),.1);
}
.form-group textarea {
  resize: vertical;
  min-height: 120px;
}
.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

/* Map */
.contact-map {
  margin-top: 48px;
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--border);
}
.contact-map iframe {
  width: 100%;
  height: 400px;
  border: 0;
  display: block;
}

/* ============================================
   DOWNLOAD PAGE
   ============================================ */
.download-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 24px;
}
.download-card {
  display: flex;
  align-items: center;
  gap: 20px;
  padding: 24px;
  background: var(--bg-light);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: all var(--transition);
}
.download-card:hover {
  box-shadow: var(--shadow);
  border-color: var(--primary);
  transform: translateY(-2px);
}
.download-card .dl-icon {
  width: 56px;
  height: 56px;
  background: var(--primary);
  color: #fff;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.4rem;
  flex-shrink: 0;
}
.download-card .dl-info h4 {
  font-size: .95rem;
  color: var(--primary-dark);
  margin-bottom: 4px;
}
.download-card .dl-info p {
  font-size: .82rem;
  color: var(--text-muted);
  margin-bottom: 8px;
}
.download-card .dl-btn {
  margin-left: auto;
  font-size: .82rem;
  padding: 8px 18px;
}

/* Download Simple Grid */
.download-simple-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 20px;
}
.download-simple-item {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 18px 20px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: all var(--transition);
}
.download-simple-item:hover {
  border-color: var(--primary);
  box-shadow: var(--shadow);
}
.dl-pdf-icon {
  width: 40px;
  height: 48px;
  flex-shrink: 0;
}
.dl-pdf-icon svg {
  width: 100%;
  height: 100%;
}
.dl-filename {
  flex: 1;
  font-size: .88rem;
  color: var(--text);
  font-weight: 500;
  line-height: 1.35;
  word-break: break-all;
}
.dl-download-btn {
  width: 36px;
  height: 36px;
  border-radius: 6px;
  background: var(--primary);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition);
  flex-shrink: 0;
}
.dl-download-btn svg {
  width: 18px;
  height: 18px;
}
.dl-download-btn:hover {
  background: var(--primary-dark);
}

/* ============================================
   MOBILE MENU
   ============================================ */
.mobile-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,.4);
  z-index: 998;
  opacity: 0;
  transition: opacity var(--transition);
}
.mobile-overlay.active { display: block; opacity: 1; }

/* ============================================
   BACK TO TOP
   ============================================ */
.back-to-top {
  position: fixed;
  bottom: 32px;
  right: 32px;
  width: 44px;
  height: 44px;
  background: var(--primary);
  color: #fff;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  box-shadow: var(--shadow-lg);
  z-index: 999;
  opacity: 0;
  visibility: hidden;
  transform: translateY(16px);
  transition: all var(--transition);
}
.back-to-top.visible { opacity: 1; visibility: visible; transform: translateY(0); }
.back-to-top:hover { background: var(--primary-dark); transform: translateY(-2px); }

/* ============================================
   RESPONSIVE
   ============================================ */
@media (max-width: 1024px) {
  .hero-slide-content h1 { font-size: 2.2rem; }
  .features-grid { grid-template-columns: repeat(2, 1fr); }
  .about .container { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .product-detail-grid { grid-template-columns: 1fr; }
  .contact-grid { grid-template-columns: 1fr; }
  .about-cards-grid { grid-template-columns: repeat(2, 1fr); }
  .about-overview { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
  :root { --header-height: 60px; }
  .nav-list {
    display: none;
    position: absolute;
    top: var(--header-height);
    left: 0;
    width: 100%;
    background: var(--bg);
    flex-direction: column;
    padding: 16px;
    box-shadow: var(--shadow-lg);
    border-top: 1px solid var(--border);
  }
  .nav-list a {
    color: var(--text) !important;
  }
  .nav-list a:hover,
  .nav-list a.active {
    color: var(--primary) !important;
    background: var(--primary-light) !important;
  }
  .nav-list.open { display: flex; }
  .nav-toggle { display: flex; }
  /* 移动端汉堡图标统一白色 */
  .nav-toggle span {
    background: #fff !important;
  }
  .hero-slider { height: 480px; }
  .hero-slide-content h1 { font-size: 1.8rem; }
  .features-grid { grid-template-columns: 1fr; }
  .products-grid { grid-template-columns: 1fr; }
  .product-list-grid { grid-template-columns: 1fr; }
  .about-stats { flex-direction: column; gap: 20px; }
  .footer-grid { grid-template-columns: 1fr; }
  .features-list { grid-template-columns: 1fr; }
  .form-row { grid-template-columns: 1fr; }
  .about-cards-grid { grid-template-columns: 1fr; }
  .section { padding: 48px 0; }
  .section-title { font-size: 1.6rem; }
  .download-grid { grid-template-columns: 1fr; }
}

@media (max-width: 480px) {
  .hero-slider { height: 400px; }
  .hero-slide-content h1 { font-size: 1.5rem; }
  .hero-actions { flex-direction: column; align-items: center; }
  .hero-actions .btn { width: 100%; }
}