/* ================================================================
   鼎盛机械 — 展示网站样式
   设计理念：整洁 · 大方 · 明亮 · 舒适 · 大气
   ================================================================ */

/* ─── Reset ─── */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, sans-serif;
  color: #1e293b;
  background: #ffffff;
  line-height: 1.7;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
ul { list-style: none; }
.container { max-width: 1280px; margin: 0 auto; padding: 0 32px; }

/* ─── Design Tokens ─── */
:root {
  --c-primary: #0f2942;
  --c-primary-light: #1a3a5c;
  --c-accent: #b8860b;
  --c-accent-light: #d4a017;
  --c-accent-soft: #f5e6c8;
  --c-bg: #ffffff;
  --c-bg-soft: #f8fafc;
  --c-bg-warm: #fdfbf7;
  --c-text: #1e293b;
  --c-text-light: #64748b;
  --c-text-mute: #94a3b8;
  --c-border: #e2e8f0;
  --c-border-light: #f1f5f9;
  --c-white: #ffffff;
  --c-danger: #dc2626;
  --c-success: #059669;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.06), 0 1px 2px rgba(0,0,0,0.04);
  --shadow: 0 4px 6px -1px rgba(0,0,0,0.07), 0 2px 4px -2px rgba(0,0,0,0.05);
  --shadow-md: 0 10px 15px -3px rgba(0,0,0,0.08), 0 4px 6px -4px rgba(0,0,0,0.05);
  --shadow-lg: 0 20px 25px -5px rgba(0,0,0,0.1), 0 8px 10px -6px rgba(0,0,0,0.06);
  --shadow-xl: 0 25px 50px -12px rgba(0,0,0,0.18);
  --radius-sm: 8px;
  --radius: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --transition: all 0.35s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-fast: all 0.2s ease;
}

/* ─── Navigation ─── */
.nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 1000;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid rgba(226, 232, 240, 0.6);
  transition: var(--transition);
}
.nav.scrolled {
  background: rgba(255, 255, 255, 0.95);
  box-shadow: var(--shadow);
}
.nav-inner {
  max-width: 1280px; margin: 0 auto; padding: 0 32px;
  display: flex; align-items: center; justify-content: space-between;
  height: 76px;
}
.nav-logo { display: flex; align-items: center; gap: 12px; }
.logo-icon {
  width: 42px; height: 42px;
  background: linear-gradient(135deg, var(--c-primary), var(--c-primary-light));
  border-radius: 10px;
  display: flex; align-items: center; justify-content: center;
  color: var(--c-accent-light); font-size: 22px;
}
.logo-text {
  color: var(--c-primary); font-size: 1.3rem; font-weight: 800;
  letter-spacing: 1px;
}
.nav-links { display: flex; gap: 36px; }
.nav-links a {
  color: var(--c-text); font-size: 0.95rem; font-weight: 500;
  transition: var(--transition-fast); position: relative; padding: 4px 0;
}
.nav-links a:hover { color: var(--c-accent); }
.nav-links a.active { color: var(--c-accent); font-weight: 700; }
.nav-links a::after {
  content: ''; position: absolute; bottom: -4px; left: 50%;
  width: 0; height: 2px; background: var(--c-accent);
  transition: var(--transition-fast); transform: translateX(-50%);
}
.nav-links a:hover::after, .nav-links a.active::after { width: 100%; }
.nav-cta {
  background: var(--c-primary);
  color: var(--c-white) !important;
  padding: 11px 26px; border-radius: var(--radius-sm);
  font-weight: 600; font-size: 0.9rem;
  display: flex; align-items: center; gap: 8px;
  transition: var(--transition);
}
.nav-cta:hover {
  background: var(--c-accent); color: var(--c-white) !important;
  transform: translateY(-1px); box-shadow: 0 4px 16px rgba(184, 134, 11, 0.3);
}
.nav-toggle {
  display: none; background: none; border: none;
  color: var(--c-primary); font-size: 24px; cursor: pointer;
}

/* ─── Hero ─── */
.hero {
  position: relative; min-height: 100vh;
  display: flex; align-items: center; justify-content: center;
  overflow: hidden;
}
.hero-slider { position: absolute; inset: 0; z-index: 0; }
.hero-slide {
  position: absolute; inset: 0;
  background-size: cover; background-position: center;
  opacity: 0; transition: opacity 1.5s ease-in-out;
}
.hero-slide.active { opacity: 1; }
.hero-overlay {
  position: absolute; inset: 0;
  background: linear-gradient(135deg,
    rgba(15, 41, 66, 0.88) 0%,
    rgba(15, 41, 66, 0.72) 50%,
    rgba(15, 41, 66, 0.85) 100%);
}
.hero-content {
  position: relative; z-index: 2; text-align: center;
  padding: 120px 32px 80px; max-width: 900px;
}
.hero-badge {
  display: inline-flex; align-items: center; gap: 8px;
  background: rgba(255, 255, 255, 0.12);
  border: 1px solid rgba(212, 160, 23, 0.4);
  color: var(--c-accent-light);
  padding: 8px 20px; border-radius: 50px;
  font-size: 0.85rem; font-weight: 500; margin-bottom: 32px;
  backdrop-filter: blur(8px);
  animation: fadeInUp 0.8s ease;
}
.hero-title {
  font-size: clamp(2.5rem, 6vw, 4.5rem);
  font-weight: 900; line-height: 1.15; margin-bottom: 24px;
  animation: fadeInUp 0.8s ease 0.1s both;
}
.hero-title-line1 { display: block; color: var(--c-white); }
.hero-title-line2 {
  display: block;
  background: linear-gradient(135deg, var(--c-accent-light), #e8c96a);
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
  background-clip: text;
}
.hero-desc {
  color: rgba(255, 255, 255, 0.75); font-size: 1.2rem;
  max-width: 600px; margin: 0 auto 40px;
  animation: fadeInUp 0.8s ease 0.2s both;
}
.hero-actions {
  display: flex; gap: 16px; justify-content: center; flex-wrap: wrap;
  margin-bottom: 64px;
  animation: fadeInUp 0.8s ease 0.3s both;
}
.hero-stats {
  display: flex; justify-content: center; gap: 48px; flex-wrap: wrap;
  animation: fadeInUp 0.8s ease 0.4s both;
}
.hero-stat { text-align: center; }
.hero-stat-num {
  font-size: 2.5rem; font-weight: 900; color: var(--c-accent-light);
  line-height: 1;
}
.hero-stat-label { color: rgba(255,255,255,0.6); font-size: 0.85rem; margin-top: 6px; }
.hero-stat-divider {
  width: 1px; height: 48px;
  background: rgba(255,255,255,0.15); align-self: center;
}
.hero-scroll {
  position: absolute; bottom: 32px; left: 50%;
  transform: translateX(-50%); z-index: 2;
  color: rgba(255,255,255,0.4); font-size: 24px;
  animation: bounce 2s infinite;
}
.hero-dots {
  position: absolute; bottom: 80px; left: 50%;
  transform: translateX(-50%); z-index: 10;
  display: flex; gap: 10px;
}
.hero-dot {
  width: 12px; height: 12px; border-radius: 50%;
  background: rgba(255,255,255,0.3); cursor: pointer;
  border: none; padding: 0; transition: var(--transition-fast);
}
.hero-dot.active {
  background: var(--c-accent-light); width: 32px; border-radius: 6px;
}
.hero-arrow {
  position: absolute; top: 50%; transform: translateY(-50%); z-index: 10;
  width: 48px; height: 48px; border-radius: 50%;
  background: rgba(255,255,255,0.12);
  border: 1px solid rgba(255,255,255,0.2);
  color: var(--c-white); cursor: pointer;
  display: flex; align-items: center; justify-content: center;
  font-size: 18px; transition: var(--transition);
  backdrop-filter: blur(8px);
}
.hero-arrow:hover {
  background: rgba(212, 160, 23, 0.5); border-color: var(--c-accent-light);
}
.hero-prev { left: 24px; }
.hero-next { right: 24px; }

/* ─── 背景音乐 ─── */
.bg-music-btn {
  position: fixed; bottom: 24px; left: 24px; z-index: 999;
  width: 48px; height: 48px; border-radius: 50%;
  background: rgba(255,255,255,0.9); backdrop-filter: blur(10px);
  border: 1px solid var(--c-border);
  display: flex; align-items: center; justify-content: center;
  color: var(--c-accent); font-size: 20px; cursor: pointer;
  transition: var(--transition);
  box-shadow: var(--shadow);
}
.bg-music-btn:hover {
  background: var(--c-accent); color: var(--c-white);
  transform: scale(1.08); box-shadow: var(--shadow-md);
}
.bg-music-btn.playing i { animation: musicSpin 3s linear infinite; }
@keyframes musicSpin { from { transform: rotate(0); } to { transform: rotate(360deg); } }

/* ─── Buttons ─── */
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 12px 28px; border-radius: var(--radius-sm);
  font-weight: 600; font-size: 0.95rem; border: none; cursor: pointer;
  transition: var(--transition); font-family: inherit;
}
.btn-primary {
  background: var(--c-primary); color: var(--c-white);
}
.btn-primary:hover {
  background: var(--c-accent); transform: translateY(-2px);
  box-shadow: 0 6px 24px rgba(184, 134, 11, 0.3);
}
.btn-accent {
  background: linear-gradient(135deg, var(--c-accent), var(--c-accent-light));
  color: var(--c-white);
}
.btn-accent:hover {
  transform: translateY(-2px); box-shadow: 0 6px 24px rgba(184,134,11,0.35);
}
.btn-outline {
  background: transparent; border: 2px solid rgba(255,255,255,0.3);
  color: var(--c-white);
}
.btn-outline:hover { border-color: var(--c-accent-light); color: var(--c-accent-light); }
.btn-lg { padding: 16px 36px; font-size: 1.05rem; }
.btn-sm { padding: 8px 16px; font-size: 0.85rem; }
.btn-full { width: 100%; justify-content: center; }

/* ─── Section Common ─── */
.section { padding: 110px 0; }
.section-header { text-align: center; margin-bottom: 64px; }
.section-tag {
  display: inline-flex; align-items: center; gap: 6px;
  font-size: 0.85rem; font-weight: 600; color: var(--c-accent);
  text-transform: uppercase; letter-spacing: 2px; margin-bottom: 16px;
}
.section-title {
  font-size: clamp(2rem, 4vw, 3rem); font-weight: 900;
  color: var(--c-primary); margin-bottom: 16px;
}
.section-title.light { color: var(--c-white); }
.section-desc {
  color: var(--c-text-light); font-size: 1.1rem;
  max-width: 600px; margin: 0 auto;
}

/* ─── 公司介绍区 ─── */
.intro { background: var(--c-white); }
.intro-grid {
  display: grid; grid-template-columns: 1.1fr 1fr;
  gap: 64px; align-items: center;
}
.intro-text {
  color: var(--c-text-light); font-size: 1rem;
  line-height: 1.9; margin-bottom: 20px;
}
.intro-highlights {
  display: grid; grid-template-columns: repeat(2, 1fr);
  gap: 20px; margin-top: 36px;
}
.intro-highlight { display: flex; gap: 14px; align-items: center; }
.intro-highlight i {
  width: 48px; height: 48px; min-width: 48px; border-radius: var(--radius-sm);
  background: var(--c-accent-soft);
  display: flex; align-items: center; justify-content: center;
  color: var(--c-accent); font-size: 22px;
}
.intro-highlight strong { display: block; font-size: 0.95rem; color: var(--c-primary); }
.intro-highlight span { font-size: 0.82rem; color: var(--c-text-light); }
.intro-right { position: relative; }
.intro-image-stack { position: relative; }
.intro-img-1 {
  width: 100%; aspect-ratio: 4/3; object-fit: cover;
  border-radius: var(--radius-lg); box-shadow: var(--shadow-lg);
}
.intro-img-2 {
  position: absolute; bottom: -24px; right: -24px;
  width: 50%; aspect-ratio: 1; object-fit: cover;
  border-radius: var(--radius); border: 6px solid var(--c-white);
  box-shadow: var(--shadow-lg);
}
.intro-image-badge {
  position: absolute; top: 20px; left: -20px;
  background: var(--c-accent); color: var(--c-white);
  padding: 16px 24px; border-radius: var(--radius);
  text-align: center; box-shadow: var(--shadow-md);
}

/* ─── Products ─── */
.products { background: var(--c-bg-soft); }
.product-filter {
  display: flex; justify-content: center; gap: 12px;
  margin-bottom: 48px; flex-wrap: wrap;
}
.filter-btn {
  padding: 10px 24px; border: 2px solid var(--c-border);
  border-radius: 50px; background: var(--c-white);
  color: var(--c-text-light); font-weight: 500; cursor: pointer;
  transition: var(--transition); font-family: inherit; font-size: 0.9rem;
}
.filter-btn:hover, .filter-btn.active {
  border-color: var(--c-accent); color: var(--c-accent);
  background: var(--c-accent-soft);
}
.product-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 32px;
}
.product-card {
  background: var(--c-white); border-radius: var(--radius-lg);
  overflow: hidden; box-shadow: var(--shadow);
  transition: var(--transition); cursor: pointer;
  border: 1px solid var(--c-border-light);
}
.product-card:hover {
  transform: translateY(-8px); box-shadow: var(--shadow-xl);
  border-color: var(--c-accent-soft);
}
.product-image {
  height: 240px; overflow: hidden; background: var(--c-bg-soft);
}
.product-image img {
  width: 100%; height: 100%; object-fit: cover;
  transition: transform 0.6s;
}
.product-card:hover .product-image img { transform: scale(1.08); }
.product-info { padding: 28px; }
.product-model {
  display: inline-block; font-size: 0.8rem; font-weight: 600;
  color: var(--c-accent); background: var(--c-accent-soft);
  padding: 4px 12px; border-radius: var(--radius-sm);
}
.product-name {
  font-size: 1.25rem; font-weight: 700; margin: 12px 0;
  color: var(--c-primary);
}
.product-specs {
  display: flex; flex-direction: column; gap: 8px; margin-bottom: 20px;
}
.spec {
  display: flex; align-items: center; gap: 8px;
  font-size: 0.85rem; color: var(--c-text-light);
}
.spec i { color: var(--c-accent); font-size: 14px; min-width: 16px; }
.product-footer {
  display: flex; align-items: center; justify-content: space-between;
  padding-top: 16px; border-top: 1px solid var(--c-border-light);
}
.product-price {
  font-size: 1.4rem; font-weight: 900; color: var(--c-danger);
}

/* ─── About ─── */
.about {
  background: linear-gradient(135deg, var(--c-primary) 0%, var(--c-primary-light) 100%);
  position: relative; overflow: hidden;
}
.about::before {
  content: ''; position: absolute; top: -50%; right: -20%;
  width: 600px; height: 600px;
  background: radial-gradient(circle, rgba(212,160,23,0.08) 0%, transparent 70%);
  border-radius: 50%;
}
.about-grid {
  display: grid; grid-template-columns: 1.1fr 1fr;
  gap: 64px; align-items: center; position: relative;
}
.about-text {
  color: rgba(255,255,255,0.7); font-size: 1.05rem;
  margin: 20px 0 40px; line-height: 1.9;
}
.about-values { display: flex; flex-direction: column; gap: 24px; }
.about-value { display: flex; gap: 16px; align-items: flex-start; }
.about-value-icon {
  width: 50px; height: 50px; min-width: 50px;
  background: rgba(212,160,23,0.15); border-radius: var(--radius-sm);
  display: flex; align-items: center; justify-content: center;
  color: var(--c-accent-light); font-size: 22px;
}
.about-value h4 { color: var(--c-white); font-size: 1rem; margin-bottom: 4px; }
.about-value p { color: rgba(255,255,255,0.5); font-size: 0.85rem; }
.about-right { position: relative; }
.about-image-wrapper {
  position: relative; border-radius: var(--radius-lg); overflow: hidden;
  box-shadow: var(--shadow-xl);
}
.about-image { width: 100%; aspect-ratio: 4/3; object-fit: cover; }
.about-image-badge {
  position: absolute; bottom: 20px; right: 20px;
  background: var(--c-accent); color: var(--c-white);
  padding: 16px 24px; border-radius: var(--radius-sm); text-align: center;
}
.badge-num { display: block; font-size: 1.5rem; font-weight: 900; }
.badge-text { display: block; font-size: 0.75rem; font-weight: 500; }

/* ─── Strength ─── */
.strength { background: var(--c-white); }
.strength-grid {
  display: grid; grid-template-columns: repeat(3, 1fr);
  gap: 28px; margin-bottom: 48px;
}
.strength-card {
  background: var(--c-bg-soft); border-radius: var(--radius-lg);
  padding: 44px 32px; text-align: center;
  transition: var(--transition); border: 1px solid var(--c-border-light);
}
.strength-card:hover {
  transform: translateY(-6px); box-shadow: var(--shadow-lg);
  background: var(--c-white); border-color: var(--c-accent-soft);
}
.strength-icon {
  width: 64px; height: 64px; margin: 0 auto 20px;
  background: var(--c-accent-soft); border-radius: var(--radius);
  display: flex; align-items: center; justify-content: center;
  color: var(--c-accent); font-size: 28px;
}
.strength-num {
  font-size: 2.5rem; font-weight: 900; color: var(--c-primary); line-height: 1;
}
.strength-unit { font-size: 0.9rem; color: var(--c-text-light); margin-top: 4px; }
.strength-label { color: var(--c-text-light); font-size: 0.9rem; margin-top: 8px; }

.certs-row {
  display: flex; justify-content: center; gap: 24px; flex-wrap: wrap;
}
.cert-badge {
  display: flex; align-items: center; gap: 8px;
  padding: 12px 24px; background: var(--c-white);
  border-radius: 50px; box-shadow: var(--shadow-sm);
  font-weight: 600; color: var(--c-primary); font-size: 0.9rem;
  border: 1px solid var(--c-border-light);
}
.cert-badge i { color: var(--c-success); }

/* ─── Contact ─── */
.contact { background: var(--c-bg-soft); }
.contact-grid {
  display: grid; grid-template-columns: 1fr 1fr; gap: 48px;
}
.contact-desc { color: var(--c-text-light); margin: 16px 0 32px; }
.contact-details {
  display: flex; flex-direction: column; gap: 20px; margin-bottom: 32px;
}
.contact-item { display: flex; gap: 16px; align-items: flex-start; }
.contact-item i {
  width: 48px; height: 48px; min-width: 48px;
  background: var(--c-accent-soft); border-radius: var(--radius-sm);
  display: flex; align-items: center; justify-content: center;
  color: var(--c-accent); font-size: 20px;
}
.contact-item strong { display: block; font-size: 0.85rem; color: var(--c-primary); }
.contact-item span { font-size: 0.9rem; color: var(--c-text-light); }

.contact-im { margin-top: 8px; }
.im-title {
  font-weight: 600; color: var(--c-primary); margin-bottom: 12px;
  display: flex; align-items: center; gap: 6px;
}
.im-buttons { display: flex; gap: 12px; flex-wrap: wrap; }
.im-btn {
  padding: 12px 24px; border-radius: var(--radius-sm);
  font-weight: 600; font-size: 0.9rem; border: none; cursor: pointer;
  display: flex; align-items: center; gap: 8px;
  transition: var(--transition); font-family: inherit;
}
.im-qq { background: #12B7F5; color: var(--c-white); }
.im-qq:hover { background: #0ea5e0; transform: translateY(-2px); }
.im-wechat { background: #07C160; color: var(--c-white); }
.im-wechat:hover { background: #06ad56; transform: translateY(-2px); }
.im-online { background: var(--c-primary); color: var(--c-accent-light); }
.im-online:hover { background: var(--c-primary-light); transform: translateY(-2px); }

/* ─── Social Links ─── */
.social-links-section { margin-top: 20px; }
.social-icons-row {
  display: flex; gap: 12px; flex-wrap: wrap;
}
.social-icon {
  width: 48px; height: 48px; border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  font-size: 1.2rem; color: #fff; text-decoration: none;
  transition: var(--transition); cursor: pointer;
  box-shadow: 0 2px 8px rgba(0,0,0,0.15);
}
.social-icon:hover { transform: translateY(-4px) scale(1.1); box-shadow: 0 6px 20px rgba(0,0,0,0.25); }
.social-facebook { background: #1877F2; }
.social-x { background: #000000; }
.social-linkedin { background: #0A66C2; }
.social-line { background: #06C755; }
.social-wechat { background: #07C160; }
.social-icon.disabled { opacity: 0.35; pointer-events: none; }

/* Footer Social */
.footer-social { display: flex; gap: 10px; margin-top: 12px; }
.footer-social-icon {
  width: 36px; height: 36px; border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  font-size: 0.95rem; color: rgba(255,255,255,0.7);
  background: rgba(255,255,255,0.1); text-decoration: none;
  transition: var(--transition-fast);
}
.footer-social-icon:hover {
  color: #fff; background: rgba(255,255,255,0.25); transform: translateY(-2px);
}
.footer-social-icon.disabled { opacity: 0.3; pointer-events: none; }

.contact-form-card {
  background: var(--c-white); border-radius: var(--radius-lg);
  padding: 44px; box-shadow: var(--shadow);
}
.contact-form-card h3 {
  font-size: 1.3rem; margin-bottom: 28px;
  display: flex; align-items: center; gap: 8px;
  color: var(--c-primary);
}
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.form-group { margin-bottom: 16px; }
.form-group label {
  display: block; font-size: 0.85rem; font-weight: 600;
  margin-bottom: 6px; color: var(--c-primary);
}
.required { color: var(--c-danger); }
.form-group input, .form-group select, .form-group textarea {
  width: 100%; padding: 12px 16px;
  border: 2px solid var(--c-border); border-radius: var(--radius-sm);
  font-size: 0.95rem; font-family: inherit;
  transition: var(--transition-fast); background: var(--c-bg-soft);
}
.form-group input:focus, .form-group select:focus, .form-group textarea:focus {
  outline: none; border-color: var(--c-accent); background: var(--c-white);
  box-shadow: 0 0 0 3px rgba(184,134,11,0.1);
}

/* ─── Footer ─── */
.footer {
  background: var(--c-primary); color: rgba(255,255,255,0.6);
  padding: 64px 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(255,255,255,0.1);
}
.footer-brand p { margin-top: 12px; font-size: 0.9rem; }
.footer-logo {
  display: flex; align-items: center; gap: 10px;
  color: var(--c-white); font-size: 1.2rem; font-weight: 700;
}
.footer-links h4 { color: var(--c-white); margin-bottom: 16px; font-size: 0.95rem; }
.footer-links a, .footer-links p {
  display: block; margin-bottom: 8px; font-size: 0.9rem;
  transition: var(--transition-fast);
}
.footer-links a:hover { color: var(--c-accent-light); }
.footer-links p i { margin-right: 6px; }
.footer-bottom { padding: 20px 0; text-align: center; font-size: 0.8rem; }

/* ─── Chat Widget ─── */
.chat-widget { position: fixed; bottom: 24px; right: 24px; z-index: 999; }
.chat-fab {
  width: 60px; height: 60px; border-radius: 50%;
  background: var(--c-primary); border: none; cursor: pointer;
  display: flex; align-items: center; justify-content: center;
  font-size: 28px; color: var(--c-accent-light);
  box-shadow: var(--shadow-lg); transition: var(--transition);
}
.chat-fab:hover { transform: scale(1.1); background: var(--c-accent); color: var(--c-white); }
.chat-panel {
  position: absolute; bottom: 76px; right: 0;
  width: 380px; height: 520px;
  background: var(--c-white); border-radius: var(--radius-lg);
  box-shadow: var(--shadow-xl);
  display: none; flex-direction: column; overflow: hidden;
}
.chat-panel.open { display: flex; animation: chatOpen 0.3s ease; }
@keyframes chatOpen {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}
.chat-header {
  background: var(--c-primary); color: var(--c-white);
  padding: 16px 20px; display: flex; justify-content: space-between; align-items: center;
  font-weight: 600;
}
.chat-header-info { display: flex; align-items: center; gap: 8px; }
.chat-header .chat-status {
  width: 8px; height: 8px; border-radius: 50%;
  background: #4ade80; box-shadow: 0 0 8px #4ade80;
}
.chat-header button {
  background: rgba(255,255,255,0.15); border: none; color: var(--c-white);
  width: 32px; height: 32px; border-radius: var(--radius-sm);
  cursor: pointer; font-size: 16px;
  display: flex; align-items: center; justify-content: center;
  transition: var(--transition-fast);
}
.chat-header button:hover { background: rgba(255,255,255,0.25); }
.chat-body {
  flex: 1; padding: 16px; overflow-y: auto;
  display: flex; flex-direction: column; gap: 12px;
}
.chat-msg {
  padding: 12px 16px; border-radius: var(--radius); max-width: 85%;
  font-size: 0.9rem; line-height: 1.6;
}
.chat-msg.system {
  background: var(--c-bg-soft); color: var(--c-text);
  align-self: flex-start; border-bottom-left-radius: 4px;
}
.chat-msg.user {
  background: var(--c-primary); color: var(--c-white);
  align-self: flex-end; border-bottom-right-radius: 4px;
}
.chat-msg.auto-reply {
  background: var(--c-accent-soft); color: var(--c-text);
  align-self: flex-start; border-bottom-left-radius: 4px;
}
.chat-input {
  padding: 12px 16px; border-top: 1px solid var(--c-border-light);
  display: flex; gap: 8px;
}
.chat-input input {
  flex: 1; padding: 10px 14px;
  border: 2px solid var(--c-border); border-radius: var(--radius-sm);
  font-size: 0.9rem; font-family: inherit;
}
.chat-input input:focus { outline: none; border-color: var(--c-accent); }
.chat-input button {
  width: 42px; height: 42px; border-radius: var(--radius-sm);
  background: var(--c-primary); border: none; cursor: pointer;
  display: flex; align-items: center; justify-content: center;
  color: var(--c-accent-light); font-size: 18px;
  transition: var(--transition-fast);
}
.chat-input button:hover { background: var(--c-accent); color: var(--c-white); }

/* 在线客服 — 留言表单区 */
.chat-form-section {
  border-top: 2px dashed var(--c-border); padding: 12px;
  background: var(--c-bg-warm);
}
.chat-form-section h4 {
  font-size: 0.8rem; color: var(--c-text-light); margin-bottom: 8px;
  display: flex; align-items: center; gap: 4px;
}
.chat-form-section input {
  width: 100%; padding: 8px 10px; border: 1px solid var(--c-border);
  border-radius: var(--radius-sm); font-size: 0.82rem; margin-bottom: 6px;
  font-family: inherit;
}
.chat-form-section input:focus { outline: none; border-color: var(--c-accent); }
.chat-form-section .chat-submit-btn {
  width: 100%; padding: 8px; border: none; border-radius: var(--radius-sm);
  background: var(--c-accent); color: var(--c-white); font-weight: 600;
  font-size: 0.82rem; cursor: pointer; transition: var(--transition-fast);
}
.chat-form-section .chat-submit-btn:hover { background: var(--c-accent-light); }

/* ─── Modal ─── */
.modal-overlay {
  position: fixed; inset: 0; background: rgba(15, 41, 66, 0.6);
  z-index: 2000; display: none; align-items: center; justify-content: center;
  padding: 24px; backdrop-filter: blur(6px);
}
.modal-overlay.active { display: flex; }
.modal {
  background: var(--c-white); border-radius: var(--radius-lg);
  max-width: 900px; width: 100%; max-height: 90vh; overflow-y: auto;
  position: relative; animation: modalIn 0.35s ease;
}
.modal-sm { max-width: 440px; }
.modal-close {
  position: absolute; top: 16px; right: 16px; z-index: 10;
  width: 40px; height: 40px; border-radius: 50%;
  background: rgba(0,0,0,0.06); border: none; cursor: pointer;
  display: flex; align-items: center; justify-content: center;
  font-size: 20px; color: var(--c-text-light);
  transition: var(--transition-fast);
}
.modal-close:hover { background: rgba(0,0,0,0.1); color: var(--c-text); }
.modal-product { display: grid; grid-template-columns: 1fr 1fr; }
.modal-product-image { overflow: hidden; }
.modal-product-image img { width: 100%; height: 100%; object-fit: cover; }
.modal-product-info { padding: 40px; }
.modal-price {
  font-size: 1.8rem; font-weight: 900; color: var(--c-danger); margin: 16px 0;
}
.modal-specs {
  display: grid; grid-template-columns: 1fr 1fr;
  gap: 12px; margin-bottom: 24px;
}
.modal-spec {
  padding: 12px; background: var(--c-bg-soft);
  border-radius: var(--radius-sm); display: flex; flex-direction: column;
}
.modal-spec strong { font-size: 0.8rem; color: var(--c-text-light); }
.modal-spec span { font-size: 1rem; font-weight: 700; color: var(--c-primary); }
.modal-desc {
  color: var(--c-text-light); font-size: 0.95rem;
  line-height: 1.8; margin-bottom: 24px;
}

/* Wechat modal */
.wechat-scan { padding: 40px; text-align: center; }
.wechat-icon { font-size: 48px; color: #07C160; margin-bottom: 16px; }
.wechat-scan h3 { margin-bottom: 8px; }
.wechat-scan > p { color: var(--c-text-light); font-size: 0.9rem; margin-bottom: 24px; }
.wechat-qr-container { margin: 0 auto 16px; }
.wechat-qr-container img {
  width: 200px; height: 200px; object-fit: cover;
  border-radius: var(--radius); margin: 0 auto; display: block;
  border: 2px solid var(--c-border);
}
.wechat-qr-placeholder {
  width: 200px; height: 200px; margin: 0 auto 16px;
  background: var(--c-bg-soft); border-radius: var(--radius);
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  color: var(--c-text-light); font-size: 0.85rem;
}
.wechat-qr-placeholder i { font-size: 48px; margin-bottom: 8px; }
.wechat-tip { color: var(--c-text-light); font-size: 0.85rem; }

/* ─── Toast ─── */
.toast {
  position: fixed; top: 88px; right: 24px; z-index: 3000;
  padding: 16px 24px; border-radius: var(--radius-sm);
  background: var(--c-white); box-shadow: var(--shadow-lg);
  display: flex; align-items: center; gap: 10px;
  font-weight: 500; animation: slideIn 0.3s ease;
  transform: translateX(120%);
}
.toast.show { transform: translateX(0); }
.toast.success { border-left: 4px solid var(--c-success); }
.toast.error { border-left: 4px solid var(--c-danger); }

/* ─── Video Section ─── */
.video-section { background: var(--c-primary); position: relative; overflow: hidden; }
.video-section::before {
  content: ''; position: absolute; top: -30%; left: -10%;
  width: 500px; height: 500px;
  background: radial-gradient(circle, rgba(212,160,23,0.06) 0%, transparent 70%);
  border-radius: 50%;
}
.video-section .section-tag { color: var(--c-accent-light); }
.video-section .section-title { color: var(--c-white); }
.video-section .section-desc { color: rgba(255,255,255,0.6); }
.video-wrapper {
  max-width: 960px; margin: 0 auto;
  border-radius: var(--radius-lg); overflow: hidden;
  box-shadow: var(--shadow-xl); position: relative;
  background: #000;
}
.video-wrapper video {
  width: 100%; display: block; max-height: 540px; object-fit: cover;
}
.video-placeholder {
  height: 400px; display: flex; flex-direction: column;
  align-items: center; justify-content: center;
  background: var(--c-primary-light); color: rgba(255,255,255,0.4);
}
.video-placeholder i { font-size: 64px; margin-bottom: 16px; }
.video-placeholder p { font-size: 0.95rem; }

/* ─── Hero video slide ─── */
.hero-slide-video {
  position: absolute; inset: 0; z-index: 0;
  opacity: 0; transition: opacity 1.5s ease-in-out;
}
.hero-slide-video.active { opacity: 1; }
.hero-slide-video video {
  width: 100%; height: 100%; object-fit: cover;
}

/* ─── Animations ─── */
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(30px); }
  to { opacity: 1; transform: translateY(0); }
}
@keyframes bounce {
  0%, 100% { transform: translateX(-50%) translateY(0); }
  50% { transform: translateX(-50%) translateY(10px); }
}
@keyframes modalIn {
  from { opacity: 0; transform: scale(0.95); }
  to { opacity: 1; transform: scale(1); }
}
@keyframes slideIn {
  from { transform: translateX(120%); }
  to { transform: translateX(0); }
}

/* ─── Responsive ─── */
@media (max-width: 1024px) {
  .about-grid { grid-template-columns: 1fr; }
  .about-right { order: -1; }
  .intro-grid { grid-template-columns: 1fr; }
  .strength-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: repeat(2, 1fr); }
  .modal-product { grid-template-columns: 1fr; }
  .section { padding: 80px 0; }
}
@media (max-width: 768px) {
  .nav-links { display: none; }
  .nav-toggle { display: block; }
  .nav-links.open {
    display: flex; flex-direction: column;
    position: absolute; top: 76px; left: 0; right: 0;
    background: rgba(255,255,255,0.98); padding: 24px;
    gap: 16px; box-shadow: var(--shadow-lg);
  }
  .nav-cta { display: none; }
  .hero-title { font-size: 2rem; }
  .hero-stats { gap: 20px; }
  .hero-stat-divider { display: none; }
  .hero-stat-num { font-size: 1.8rem; }
  .hero-arrow { width: 36px; height: 36px; font-size: 14px; }
  .intro-highlights { grid-template-columns: 1fr; }
  .product-grid { grid-template-columns: 1fr; }
  .contact-grid { grid-template-columns: 1fr; }
  .form-row { grid-template-columns: 1fr; }
  .strength-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .chat-panel { width: calc(100vw - 32px); height: 450px; }
  .container { padding: 0 20px; }
  .section { padding: 60px 0; }
}