/* ============================================
   华拓高科 企业官网 样式 v2
   ============================================ */

/* ----- Reset & Base ----- */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }

:root {
  --bg-white: #ffffff;
  --bg-light: #f5f7fa;
  --bg-section: #f0f4f8;
  --bg-card: #ffffff;
  --bg-card-hover: #f0f7ff;
  --bg-dropdown: #ffffff;
  --border: rgba(0,0,0,.08);
  --border-light: rgba(0,0,0,.12);
  --text-primary: #1a1a2e;
  --text-secondary: #555555;
  --accent: #2196F3;
  --accent-light: #42A5F5;
  --accent-lighter: #90CAF9;
  --accent-glow: rgba(33,150,243,.1);
  --accent-strong: rgba(33,150,243,.2);
  --gradient-accent: linear-gradient(135deg, #42A5F5 0%, #90CAF9 100%);
  --gradient-accent-strong: linear-gradient(135deg, #2196F3 0%, #64B5F6 100%);
  --success: #4caf50;
  --gradient-hero: linear-gradient(135deg, #f0f4f8 0%, #e8f0fe 50%, #f5f7fa 100%);
  --radius: 12px;
  --radius-lg: 16px;
  --transition: .3s cubic-bezier(.4,0,.2,1);
  --nav-height: 66px;
}

html { scroll-behavior: smooth; font-size: 16px; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
  background: var(--bg-white);
  color: var(--text-primary);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

.container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
button { cursor: pointer; border: none; font-family: inherit; }

/* ----- Header ----- */
.header {
  position: fixed; top: 0; left: 0; right: 0; z-index: 1000;
  height: var(--nav-height);
  transition: var(--transition);
}
.header.scrolled {
  background: rgba(255,255,255,.94);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border);
  box-shadow: 0 1px 8px rgba(0,0,0,.06);
}

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

.logo-wrap {
  display: flex; align-items: center; gap: 10px; z-index: 1001;
}
.logo-img { width: auto; height: 42px; border-radius: 4px; object-fit: contain; display: block; }

/* ============= Navigation ============= */
.nav { display: flex; align-items: center; gap: 6px; }

.nav-link {
  display: inline-flex; align-items: center; gap: 4px;
  font-size: 14px; color: var(--text-secondary);
  padding: 8px 14px; border-radius: 6px;
  transition: var(--transition);
  white-space: nowrap;
}
.nav-link:hover { color: var(--text-primary); background: rgba(0,0,0,.04); }
.nav-link.active { color: var(--accent); background: var(--accent-glow); }

/* -- Lang Toggle -- */
.lang-btn {
  display: inline-flex; align-items: center; justify-content: center;
  width: 38px; height: 38px; border-radius: 50%;
  font-size: 13px; font-weight: 600;
  color: var(--text-secondary); background: var(--bg-light);
  border: 1px solid var(--border);
  cursor: pointer; transition: var(--transition);
  margin-left: 6px; flex-shrink: 0;
  font-family: inherit;
}
.lang-btn:hover { background: var(--accent-glow); color: var(--accent); }
.lang-btn.lang-active { background: var(--accent); color: #fff; border-color: var(--accent); }

/* -- Nav Dropdown -- */
.nav-dropdown { position: static; }
.nav-dropdown:hover .nav-drop-trigger { color: var(--text-primary); background: rgba(0,0,0,.04); }
.nav-dropdown:hover .nav-drop-trigger svg { transform: rotate(180deg); }
.nav-drop-trigger svg {
  width: 10px; height: 6px; transition: transform .25s ease;
}

.nav-dropdown-panel {
  position: absolute; top: var(--nav-height); left: 0; right: 0;
  background: var(--bg-dropdown);
  border-bottom: 2px solid var(--accent);
  opacity: 0; visibility: hidden; transform: translateY(-8px);
  transition: all .25s ease;
  z-index: 999;
  box-shadow: 0 20px 40px rgba(0,0,0,.12);
  max-height: 0;
  overflow: hidden;
}
.nav-dropdown:hover .nav-dropdown-panel {
  opacity: 1; visibility: visible; transform: translateY(0);
  max-height: 420px;
}

.mega-inner {
  max-width: 1200px; margin: 0 auto; padding: 32px 24px;
  display: flex; gap: 40px;
}

.mega-desc {
  flex: 0 0 220px;
  padding-right: 32px; border-right: 1px solid var(--border);
}
.mega-icon { margin-bottom: 12px; color: var(--accent); }
.mega-desc h3 { font-size: 18px; margin-bottom: 8px; color: var(--text-primary); }
.mega-desc p { font-size: 13px; color: var(--text-muted); line-height: 1.6; }

.mega-links { flex: 1; display: flex; gap: 40px; }

.mega-col h4 { font-size: 13px; margin-bottom: 10px; }
.mega-col h4 a { color: var(--accent-light); }
.mega-col h4 a:hover { color: var(--accent); }
.mega-col > a {
  display: block; font-size: 13px; color: var(--text-secondary);
  padding: 5px 0; transition: var(--transition);
}
.mega-col > a:hover { color: var(--accent); }

/* Mega Services grid */
.mega-services {
  flex: 1; display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px;
}
.mega-service-item {
  background: rgba(33,150,243,.03); border: 1px solid var(--border);
  border-radius: 10px; padding: 16px;
  transition: var(--transition);
}
.mega-service-item:hover { background: var(--accent-glow); border-color: var(--accent); }
.msi-icon { color: var(--accent); margin-bottom: 8px; }
.mega-service-item h4 { font-size: 14px; margin-bottom: 4px; }
.mega-service-item p { font-size: 12px; color: var(--text-muted); line-height: 1.5; }

/* Desktop nav only: hide dropdown panels on mobile */
@media (max-width: 768px) {
  .nav-dropdown-panel { display: none !important; }
  .nav-dropdown:hover .nav-dropdown-panel { display: none !important; }
}

/* Mobile Menu Toggle */
.menu-toggle {
  display: none; flex-direction: column; gap: 5px;
  background: none; padding: 4px; z-index: 1001;
}
.menu-toggle span {
  width: 24px; height: 2px; background: var(--text-primary);
  transition: var(--transition); border-radius: 2px;
}

/* ----- Hero ----- */
.hero {
  min-height: 100vh;
  display: flex; align-items: center; justify-content: center;
  position: relative;
  background: linear-gradient(160deg, #e8f0fe 0%, #f0f4ff 30%, #f5f0ff 60%, #eef4fa 100%);
  overflow: hidden;
}

.hero-bg {
  position: absolute; inset: 0;
  background:
    radial-gradient(ellipse at 20% 30%, rgba(144,202,249,.15) 0%, transparent 50%),
    radial-gradient(ellipse at 80% 70%, rgba(179,157,219,.1) 0%, transparent 50%),
    radial-gradient(ellipse at 50% 20%, rgba(128,222,234,.08) 0%, transparent 50%);
}

/* Cosmic background decoration */
.hero-cosmic {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0.8;
}
.hero-cosmic img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.hero-particles { position: absolute; inset: 0; }
.particle {
  position: absolute;
  width: 3px; height: 3px;
  background: var(--accent-light);
  border-radius: 50%;
  animation: float 6s ease-in-out infinite;
  opacity: 0;
}
@keyframes float {
  0%, 100% { transform: translateY(0) scale(1); opacity: 0; }
  50% { opacity: 0.5; transform: translateY(-40px) scale(1.5); }
}

.hero-content { text-align: center; position: relative; z-index: 2; padding-top: 60px; }
.hero-title { margin-bottom: 24px; }
.hero-sub {
  display: block; font-size: 38px; color: var(--text-primary);
  margin-bottom: 12px; font-weight: 700; letter-spacing: 3px;
}
.hero-main {
  display: block; font-size: clamp(32px, 5vw, 56px);
  font-weight: 800; line-height: 1.2;
  background: linear-gradient(135deg, #1a1a2e 0%, #42A5F5 50%, #7E57C2 100%);
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
}
.hero-main em { font-style: normal; -webkit-text-fill-color: var(--accent); }

.hero-desc {
  font-size: 17px; color: var(--text-secondary);
  max-width: 600px; margin: 0 auto 36px;
  line-height: 1.8;
}

.hero-btns { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; margin-bottom: 48px; }

/* Hero Features Row */
.hero-features {
  display: flex; justify-content: center; gap: 40px;
  flex-wrap: wrap;
}
.hf-item {
  display: flex; align-items: center; gap: 8px;
  font-size: 14px; color: var(--text-secondary);
}
.hf-icon { font-size: 20px; }

.hero-scroll {
  position: absolute; bottom: 40px; left: 50%; transform: translateX(-50%);
  display: flex; flex-direction: column; align-items: center; gap: 6px;
  color: var(--text-muted); font-size: 12px;
  animation: bounce 2s ease-in-out infinite;
}
@keyframes bounce {
  0%, 100% { transform: translateX(-50%) translateY(0); }
  50% { transform: translateX(-50%) translateY(8px); }
}

/* ----- Buttons ----- */
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 12px 28px; border-radius: 8px;
  font-size: 15px; font-weight: 600;
  transition: var(--transition);
}
.btn-primary {
  background: var(--gradient-accent-strong); color: #fff;
  box-shadow: 0 4px 20px rgba(33,150,243,.25);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 8px 30px rgba(33,150,243,.35); filter: brightness(1.05); }
.btn-outline {
  border: 1px solid var(--border-light); color: var(--text-primary);
}
.btn-outline:hover { border-color: var(--accent); background: rgba(33,150,243,.08); }

/* ----- Section ----- */
.section { padding: 100px 0; }

.section-header { text-align: center; margin-bottom: 60px; }
.section-title {
  font-size: 36px; font-weight: 700; margin-bottom: 12px;
  background: var(--gradient-accent-strong);
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
}
.section-sub {
  font-size: 16px; color: var(--text-secondary);
  max-width: 600px; margin: 0 auto;
}

/* ----- About ----- */
.about-grid {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px;
  margin-bottom: 80px;
}
.about-card {
  background: var(--bg-card); border: 1px solid var(--border);
  border-radius: var(--radius-lg); padding: 32px 24px;
  transition: var(--transition);
  text-align: center;
  box-shadow: 0 2px 8px rgba(0,0,0,.04);
}
.about-card:hover {
  border-color: var(--accent-lighter);
  transform: translateY(-4px);
  box-shadow: 0 12px 40px rgba(66,165,245,.15);
}
.about-icon {
  width: 64px; height: 64px; margin: 0 auto 20px;
  display: flex; align-items: center; justify-content: center;
  background: var(--gradient-accent); border-radius: 50%;
  color: #fff;
}
.about-card h3 { font-size: 20px; margin-bottom: 12px; }
.about-card p { font-size: 14px; color: var(--text-secondary); line-height: 1.7; }

/* -- Advantage Section -- */
.advantage-section { padding-top: 20px; }
.adv-title { font-size: 28px; font-weight: 700; margin-bottom: 8px; }
.adv-desc { font-size: 15px; color: var(--text-secondary); }

.adv-grid {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px;
  margin-top: 48px;
}
.adv-card {
  background: var(--bg-card); border: 1px solid var(--border);
  border-radius: var(--radius-lg); padding: 32px 24px;
  position: relative; overflow: hidden;
  transition: var(--transition);
  box-shadow: 0 2px 8px rgba(0,0,0,.04);
}
.adv-card:hover {
  border-color: var(--accent);
  transform: translateY(-3px);
  box-shadow: 0 8px 30px rgba(33,150,243,.12);
}
.adv-number {
  font-size: 40px; font-weight: 800; color: var(--accent);
  line-height: 1; margin-bottom: 12px;
}
.adv-card h4 { font-size: 18px; margin-bottom: 10px; }
.adv-card p { font-size: 13px; color: var(--text-secondary); line-height: 1.7; }

/* ----- Products ----- */
.products {
  background: linear-gradient(180deg, #f0f5ff 0%, #eef3fe 25%, #f0f0ff 50%, #f5f0ff 75%, #f8faff 100%);
}

.product-tabs {
  display: flex; justify-content: center; gap: 8px; margin-bottom: 48px;
  flex-wrap: wrap;
}
.prod-tab {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 10px 20px; border-radius: 8px;
  background: var(--bg-white); color: var(--text-secondary);
  font-size: 14px; font-weight: 500;
  border: 1px solid var(--border);
  transition: var(--transition);
}
.prod-tab:hover { color: var(--text-primary); border-color: var(--accent); }
.prod-tab.active {
  background: var(--gradient-accent); color: #fff;
  border-color: transparent;
}

/* Product carousel indicator */
.product-tabs.carousel-active::after {
  content: '● 自动切换中';
  display: inline-block;
  font-size: 12px;
  background: var(--gradient-accent);
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
  margin-left: 12px;
  vertical-align: middle;
  animation: carouselPulse 2s ease-in-out infinite;
}
@keyframes carouselPulse {
  0%, 100% { opacity: 0.4; }
  50% { opacity: 1; }
}

.prod-section { display: none; }
.prod-section.active { display: block; animation: fadeIn .4s ease; }

@keyframes fadeIn { from { opacity: 0; transform: translateY(12px); } to { opacity: 1; transform: translateY(0); } }

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

.prod-card {
  background: linear-gradient(135deg, #ffffff 0%, #f8faff 50%, #f5f0ff 100%);
  border: 1px solid rgba(124,77,255,.08);
  border-radius: var(--radius-lg);
  padding: 0;
  transition: all .35s cubic-bezier(.4,0,.2,1);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  position: relative;
}
/* Tech accent line on top of card */
.prod-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 3px;
  background: linear-gradient(90deg, transparent, #42A5F5 20%, #7E57C2 50%, #42A5F5 80%, transparent);
  opacity: 0.7;
  z-index: 1;
}
/* Subtle glow halo on card */
.prod-card::after {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse at 50% 0%, rgba(66,165,245,.03) 0%, transparent 70%);
  pointer-events: none;
}
.prod-img-wrap {
  width: 100%; height: 200px; overflow: hidden;
  background: linear-gradient(135deg, #eef3fe 0%, #f0f0ff 50%, #f5f0ff 100%);
  display: flex;
  align-items: center; justify-content: center;
}
.prod-img-wrap img {
  width: 100%; height: 100%; object-fit: cover;
  transition: transform .4s ease;
}
.prod-card:hover .prod-img-wrap img {
  transform: scale(1.05);
}
/* 加热系列图片完整显示 */
.prod-section[data-section="2"] .prod-img-wrap {
  height: 320px;
  background: #f5f7fa;
}
.prod-section[data-section="2"] .prod-img-wrap img {
  object-fit: contain;
  padding: 10px;
  box-sizing: border-box;
}
.prod-card-body {
  padding: 24px 28px;
}
.prod-card:hover {
  border-color: rgba(124,77,255,.2);
  box-shadow:
    0 8px 32px rgba(66,165,245,.15),
    0 0 0 1px rgba(124,77,255,.06);
  transform: translateY(-4px);
}
.prod-card h4 {
  font-size: 18px; margin-bottom: 14px;
  background: var(--gradient-accent-strong);
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
}
.prod-specs {
  display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 14px;
}
.prod-specs span {
  font-size: 12px; padding: 4px 10px;
  background: linear-gradient(135deg, rgba(66,165,245,.12) 0%, rgba(124,77,255,.08) 100%);
  color: #5c6bc0;
  border-radius: 4px; font-weight: 500;
}
.prod-card p { font-size: 13px; color: var(--text-secondary); margin-bottom: 16px; line-height: 1.6; }
.prod-specs-detail {
  font-size: 12px; color: var(--text-secondary); line-height: 1.7;
  margin-bottom: 12px; padding: 10px 12px;
  background: linear-gradient(135deg, rgba(66,165,245,.05) 0%, rgba(124,77,255,.03) 100%);
  border-radius: 6px;
  border-left: 3px solid #7E57C2;
}
.prod-specs-detail strong { color: var(--text-primary); }
.prod-apps { display: flex; flex-wrap: wrap; gap: 6px; }
.prod-apps span {
  font-size: 11px; padding: 3px 8px;
  background: linear-gradient(135deg, rgba(66,165,245,.08) 0%, rgba(124,77,255,.05) 100%);
  color: #5c6bc0;
  border-radius: 4px;
}

/* ----- Product Gallery ----- */
.prod-gallery { position: relative; overflow: hidden; }
.gallery-slides { position: relative; width: 100%; height: 100%; }
.gallery-slide {
  position: absolute; inset: 0;
  display: flex; align-items: center; justify-content: center;
  opacity: 0; visibility: hidden;
  transition: opacity .35s ease, visibility .35s ease;
  background: var(--bg-light);
}
.gallery-slide.active { opacity: 1; visibility: visible; position: relative; }
.gallery-slide img { width: 100%; height: 100%; object-fit: cover; }
.gallery-tag {
  position: absolute; top: 10px; right: 10px;
  font-size: 11px; padding: 3px 10px;
  background: rgba(33,150,243,.85); color: #fff;
  border-radius: 12px; font-weight: 500;
  pointer-events: none;
}
.gallery-dots {
  position: absolute; bottom: 10px; left: 0; right: 0;
  display: flex; justify-content: center; gap: 8px;
  z-index: 2;
}
.gallery-dot {
  width: 8px; height: 8px; border-radius: 50%;
  background: rgba(255,255,255,.5);
  cursor: pointer; transition: var(--transition);
  border: 1px solid rgba(0,0,0,.1);
}
.gallery-dot.active { background: var(--accent); border-color: var(--accent); transform: scale(1.3); }
.gallery-dot:hover { background: rgba(255,255,255,.8); }

/* ----- Stats ----- */
.stats { background: var(--bg-white); padding: 80px 0; }
.stat-num {
  font-size: 48px; font-weight: 800;
  background: var(--gradient-accent-strong);
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
  line-height: 1.2;
}
.stat-label { font-size: 14px; color: var(--text-secondary); margin-top: 8px; }

/* ----- Services ----- */
.services { background: var(--bg-light); }
.services-grid {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px;
}

.service-card {
  background: var(--bg-card); border: 1px solid var(--border);
  border-radius: var(--radius-lg); padding: 32px 24px;
  text-align: center;
  transition: var(--transition);
  position: relative; overflow: hidden;
  box-shadow: 0 2px 8px rgba(0,0,0,.04);
}
.service-card:hover {
  border-color: var(--accent);
  transform: translateY(-4px);
  box-shadow: 0 12px 40px rgba(33,150,243,.12);
}
.service-card::after {
  content: ''; position: absolute; bottom: 0; left: 0; right: 0;
  height: 3px; background: linear-gradient(90deg, transparent, var(--accent), transparent);
  opacity: 0; transition: var(--transition);
}
.service-card:hover::after { opacity: 1; }
.svc-icon {
  width: 72px; height: 72px; margin: 0 auto 20px;
  display: flex; align-items: center; justify-content: center;
  background: var(--gradient-accent); border-radius: 50%;
  color: #fff;
}
.service-card h4 { font-size: 18px; margin-bottom: 10px; }
.service-card p { font-size: 13px; color: var(--text-secondary); line-height: 1.7; margin-bottom: 16px; }
.svc-tags { display: flex; flex-wrap: wrap; gap: 6px; justify-content: center; }
.svc-tags span {
  font-size: 11px; padding: 3px 10px;
  background: rgba(66,165,245,.1); color: var(--accent-light);
  border-radius: 20px;
}

/* ----- Solutions ----- */
.solutions-grid {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px;
}

.solution-card {
  background: var(--bg-card); border: 1px solid var(--border);
  border-radius: var(--radius-lg); padding: 24px;
  transition: var(--transition);
  box-shadow: 0 2px 8px rgba(0,0,0,.04);
}
.solution-card:hover { border-color: var(--accent); transform: translateY(-2px); }
.solution-badge {
  display: inline-block; font-size: 12px; padding: 3px 10px;
  background: var(--accent-glow); color: var(--accent);
  border-radius: 20px; margin-bottom: 12px;
}
.solution-card h4 { font-size: 15px; margin-bottom: 16px; color: var(--text-primary); }
.solution-data { display: flex; flex-wrap: wrap; gap: 16px; }
.data-item { display: flex; flex-direction: column; }
.data-val {
  font-size: 22px; font-weight: 700; line-height: 1.2;
  color: var(--accent);
}
.data-label { font-size: 11px; color: var(--text-muted); margin-top: 2px; }

/* ----- Contact ----- */
.contact {
  background: linear-gradient(135deg, #dbeafe 0%, #eff6ff 100%);
  border-top: 1px solid var(--border);
}
.contact-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; align-items: start; }

.contact-info { display: flex; flex-direction: column; gap: 28px; }
.contact-item {
  display: flex; gap: 16px; align-items: flex-start;
  color: var(--text-secondary);
}
.contact-item svg { flex-shrink: 0; color: var(--accent-lighter); margin-top: 2px; }
.contact-item h5 { font-size: 15px; color: var(--text-primary); margin-bottom: 4px; }
.contact-item p { font-size: 14px; color: var(--text-primary); font-weight: 500; }
.contact-item p a,
.footer-contact p a {
  color: inherit;
  text-decoration: none;
}
.contact-item p a:hover,
.footer-contact p a:hover {
  color: var(--accent);
}

.contact-form {
  background: var(--bg-card); border: 1px solid var(--border);
  border-radius: var(--radius-lg); padding: 36px;
}
.contact-form h4 { font-size: 22px; margin-bottom: 24px; }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; margin-bottom: 14px; }
.contact-form input, .contact-form textarea {
  width: 100%; padding: 12px 16px;
  background: var(--bg-white); border: 1px solid var(--border);
  border-radius: 8px; color: var(--text-primary);
  font-size: 14px; font-family: inherit;
  transition: var(--transition);
  outline: none;
}
.contact-form input:focus, .contact-form textarea:focus {
  border-color: var(--accent); box-shadow: 0 0 0 3px var(--accent-glow);
}
.contact-form textarea { resize: vertical; }
.contact-form button { width: 100%; justify-content: center; margin-top: 8px; }

/* ----- Footer ----- */
.footer {
  background: var(--bg-light); border-top: 1px solid var(--border);
  padding: 60px 0 30px;
}
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1.5fr; gap: 40px; margin-bottom: 40px; }
.footer-logo { width: auto; height: 56px; border-radius: 6px; margin-bottom: 12px; object-fit: contain; }
.footer-brand h4 { font-size: 16px; margin-bottom: 4px; color: var(--text-primary); }
.footer-brand p { font-size: 13px; color: var(--text-secondary); }
.footer-tagline { margin-top: 10px; color: var(--accent) !important; }

.footer-links h5 { font-size: 14px; margin-bottom: 14px; color: var(--text-primary); }
.footer-links a {
  display: block; font-size: 13px; color: var(--text-secondary);
  margin-bottom: 8px; transition: var(--transition);
}
.footer-links a:hover { color: var(--accent); }
.footer-contact h5 { font-size: 14px; margin-bottom: 14px; color: var(--text-primary); }
.footer-contact p { font-size: 13px; color: var(--text-primary); margin-bottom: 6px; }
.footer-hours { margin-top: 12px; color: var(--accent) !important; font-weight: 500; }
.footer-bottom {
  padding-top: 24px; border-top: 1px solid var(--border);
  text-align: center;
}
.footer-bottom p { font-size: 13px; color: var(--text-secondary); }

/* ----- To Top ----- */
.to-top-btn {
  position: fixed; bottom: 32px; right: 32px; z-index: 999;
  width: 44px; height: 44px; border-radius: 50%;
  background: var(--accent); color: #fff;
  display: flex; align-items: center; justify-content: center;
  box-shadow: 0 4px 16px var(--accent-glow);
  opacity: 0; visibility: hidden;
  transition: var(--transition);
}
.to-top-btn.show { opacity: 1; visibility: visible; }
.to-top-btn:hover { transform: translateY(-3px); }

/* ----- Success Toast ----- */
.toast {
  position: fixed; top: 24px; left: 50%; transform: translateX(-50%);
  background: var(--success); color: #fff;
  padding: 12px 28px; border-radius: 8px;
  font-size: 14px; font-weight: 500;
  z-index: 9999;
  animation: toastIn .4s ease, toastOut .4s ease 2.6s forwards;
  white-space: nowrap;
}
@keyframes toastIn { from { opacity: 0; transform: translateX(-50%) translateY(-12px); } to { opacity: 1; transform: translateX(-50%) translateY(0); } }
@keyframes toastOut { from { opacity: 1; } to { opacity: 0; transform: translateX(-50%) translateY(-12px); } }

/* ----- Graphene Background Overlay ----- */
.section {
  position: relative;
}
.section::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image: url('/images/graphene-bg.svg');
  background-repeat: repeat;
  background-size: 300px 260px;
  pointer-events: none;
  z-index: 0;
}

/* Tech decorative rings -科技感装饰圆环 */
.section::after {
  content: '';
  position: absolute;
  pointer-events: none;
  z-index: 0;
  border-radius: 50%;
}

/* About section: tech ring decoration */
.section.about::after {
  width: 500px; height: 500px;
  border: 1px solid rgba(33,150,243,.08);
  top: -100px; right: -150px;
}

/* Products section: tech ring */
.section.products::after {
  width: 400px; height: 400px;
  border: 1px solid rgba(33,150,243,.06);
  bottom: -80px; left: -120px;
}

/* Services section: tech ring */
.section.services::after {
  width: 350px; height: 350px;
  border: 1px solid rgba(33,150,243,.07);
  top: 50%; right: -100px;
  transform: translateY(-50%);
}

/* Contact section: tech ring */
.section.contact::after {
  width: 300px; height: 300px;
  border: 1px solid rgba(33,150,243,.06);
  bottom: -60px; right: -80px;
}

.section > .container {
  position: relative;
  z-index: 1;
}
.section-header {
  position: relative;
  z-index: 1;
}

/* About section - tech gradient background */
.section.about {
  background: linear-gradient(180deg, var(--bg-white) 0%, rgba(33,150,243,.02) 50%, var(--bg-light) 100%);
}
.section.about::before {
  opacity: 1;
}

/* Products section */
.products {
  background: linear-gradient(180deg, #f0f5ff 0%, #eef3fe 25%, #f0f0ff 50%, #f5f0ff 75%, #f8faff 100%);
}
.products::before {
  opacity: 0.8;
}

/* Services section */
.services {
  background: var(--bg-white);
}
.services::before {
  opacity: 0.7;
}

/* Stats section */
.stats {
  background: linear-gradient(135deg, var(--bg-white) 0%, rgba(33,150,243,.03) 100%);
}

/* Solutions section */
.section.solutions {
  background: var(--bg-light);
}

/* Contact section */
.contact {
  background: var(--bg-white);
}
.contact::before {
  opacity: 0.6;
}

/* Footer dark tech background */
.footer {
  background: linear-gradient(135deg, #e8f0fe 0%, #f0f4ff 50%, #f5f0ff 100%);
  border-top: 1px solid var(--border);
  position: relative;
  overflow: hidden;
}
.footer::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image: url('/images/graphene-bg.svg');
  background-repeat: repeat;
  background-size: 300px 260px;
  opacity: 0.5;
  pointer-events: none;
}

/* ----- Responsive ----- */
@media (max-width: 1024px) {
  .about-grid { grid-template-columns: repeat(2, 1fr); }
  .adv-grid { grid-template-columns: repeat(2, 1fr); }
  .prod-grid { grid-template-columns: repeat(2, 1fr); }
  .services-grid { grid-template-columns: repeat(2, 1fr); }
  .solutions-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: repeat(2, 1fr); }
  .mega-inner { flex-direction: column; }
  .mega-desc { flex: none; border-right: none; border-bottom: 1px solid var(--border); padding: 0 0 16px 0; }
}

@media (max-width: 768px) {
  .section { padding: 70px 0; }
  .section-title { font-size: 28px; }

  .nav {
    position: fixed; top: 0; right: -100%;
    width: 280px; height: 100vh;
    flex-direction: column; gap: 0;
    background: var(--bg-white);
    padding: 80px 32px 32px;
    border-left: 1px solid var(--border);
    transition: var(--transition);
    overflow-y: auto;
    align-items: stretch;
    box-shadow: -4px 0 20px rgba(0,0,0,.1);
  }
  .nav.open { right: 0; }
  .menu-toggle { display: flex; }

  .hero-content { padding-top: 100px; }
  .hero-sub { font-size: 28px; font-weight: 700; }
  .hero-main { font-size: clamp(18px, 4.5vw, 30px); }
  .hero-features { gap: 20px; }
  .hf-item { font-size: 12px; }

  .about-grid { grid-template-columns: 1fr; }
  .adv-grid { grid-template-columns: 1fr; }
  .prod-grid { grid-template-columns: 1fr; }
  .services-grid { grid-template-columns: 1fr; }
  .solutions-grid { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); gap: 24px; }
  .contact-grid { grid-template-columns: 1fr; }
  .form-row { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; gap: 28px; }
  .product-tabs { flex-direction: column; align-items: stretch; }
  .mega-links { flex-wrap: wrap; gap: 20px; }
  .mega-col { flex: 1 1 45%; }
  .mega-services { grid-template-columns: repeat(2, 1fr); }
}

/* ====== News Section ====== */
.news-section {
  background: var(--bg-section);
}
.news-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  margin-top: 20px;
}
.news-card {
  background: var(--bg-card);
  border-radius: var(--radius);
  padding: 28px 24px;
  border: 1px solid var(--border);
  transition: var(--transition);
}
.news-card:hover {
  border-color: var(--accent);
  box-shadow: 0 4px 20px var(--accent-glow);
  transform: translateY(-3px);
}
.news-tag {
  display: inline-block;
  font-size: 12px;
  font-weight: 600;
  color: var(--accent);
  background: var(--accent-glow);
  padding: 3px 10px;
  border-radius: 20px;
  margin-bottom: 12px;
}
.news-date {
  display: block;
  font-size: 13px;
  color: var(--text-muted);
  margin-bottom: 10px;
}
.news-card h4 {
  font-size: 16px;
  color: var(--text-primary);
  margin-bottom: 10px;
  line-height: 1.4;
}
.news-card p {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.7;
}
@media (max-width: 768px) {
  .news-grid { grid-template-columns: 1fr; }
}