:root {
  --color-primary: #0d6e6e;
  --color-primary-dark: #094949;
  --color-primary-light: #14a3a3;
  --color-accent: #f59e0b;
  --color-bg: #f4f7f8;
  --color-surface: #ffffff;
  --color-text: #1a2332;
  --color-text-muted: #5c6b7a;
  --color-border: #e2e8f0;
  --shadow-sm: 0 1px 3px rgba(15, 23, 42, 0.08);
  --shadow-md: 0 8px 24px rgba(15, 23, 42, 0.1);
  --shadow-lg: 0 20px 48px rgba(15, 23, 42, 0.14);
  --radius: 12px;
  --radius-lg: 20px;
  --max-width: 1160px;
  --header-h: 72px;
  --font: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
}

*, *::before, *::after { box-sizing: border-box; }

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

body {
  margin: 0;
  font-family: var(--font);
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; height: auto; display: block; }

a { color: var(--color-primary); text-decoration: none; transition: color 0.2s; }
a:hover { color: var(--color-primary-light); }

.container {
  width: min(var(--max-width), calc(100% - 2rem));
  margin-inline: auto;
}

/* Header */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  height: var(--header-h);
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
  transition: box-shadow 0.3s;
}

.site-header.scrolled { box-shadow: var(--shadow-sm); }

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--header-h);
  gap: 1rem;
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  color: var(--color-text);
  font-weight: 700;
  font-size: 1.1rem;
  white-space: nowrap;
}

.logo-mark {
  width: 36px;
  height: 36px;
  border-radius: 10px;
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-light));
  display: grid;
  place-items: center;
  color: #fff;
  font-size: 0.85rem;
  font-weight: 800;
}

.nav-desktop {
  display: flex;
  align-items: center;
  gap: 1.75rem;
}

.nav-desktop a {
  color: var(--color-text-muted);
  font-size: 0.95rem;
  font-weight: 500;
}

.nav-desktop a:hover { color: var(--color-primary); }

.header-phone {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.5rem 1rem;
  background: var(--color-primary);
  color: #fff !important;
  border-radius: 999px;
  font-weight: 600;
  font-size: 0.9rem;
  white-space: nowrap;
}

.header-phone:hover { background: var(--color-primary-dark); color: #fff !important; }

.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
}

.nav-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--color-text);
  margin: 5px 0;
  transition: 0.3s;
}

.nav-mobile {
  display: none;
  position: fixed;
  top: var(--header-h);
  left: 0;
  right: 0;
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  padding: 1rem;
  box-shadow: var(--shadow-md);
  z-index: 99;
}

.nav-mobile.open { display: block; }

.nav-mobile a {
  display: block;
  padding: 0.75rem 0;
  color: var(--color-text);
  font-weight: 500;
  border-bottom: 1px solid var(--color-border);
}

/* Hero */
.hero {
  position: relative;
  min-height: 92vh;
  display: flex;
  align-items: center;
  padding-top: var(--header-h);
  background: linear-gradient(135deg, rgba(9, 73, 73, 0.88) 0%, rgba(13, 110, 110, 0.78) 50%, rgba(20, 163, 163, 0.65) 100%),
              url("/Images/bg.webp") center/cover no-repeat;
  color: #fff;
}

.hero-inner { padding: 4rem 0; }

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.35rem 0.9rem;
  background: rgba(255, 255, 255, 0.15);
  border: 1px solid rgba(255, 255, 255, 0.25);
  border-radius: 999px;
  font-size: 0.85rem;
  margin-bottom: 1.25rem;
}

.hero h1 {
  font-size: clamp(2rem, 5vw, 3.25rem);
  font-weight: 800;
  line-height: 1.2;
  margin: 0 0 1rem;
  letter-spacing: -0.02em;
}

.hero-desc {
  font-size: clamp(1rem, 2vw, 1.15rem);
  opacity: 0.92;
  max-width: 640px;
  margin-bottom: 2rem;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-bottom: 3rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.85rem 1.75rem;
  border-radius: 999px;
  font-weight: 600;
  font-size: 0.95rem;
  border: 2px solid transparent;
  cursor: pointer;
  transition: all 0.2s;
}

.btn-primary {
  background: var(--color-accent);
  color: #1a2332;
}

.btn-primary:hover {
  background: #e08e00;
  color: #1a2332;
  transform: translateY(-1px);
}

.btn-outline {
  background: transparent;
  color: #fff;
  border-color: rgba(255, 255, 255, 0.6);
}

.btn-outline:hover {
  background: rgba(255, 255, 255, 0.12);
  color: #fff;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1rem;
}

.stat-card {
  background: rgba(255, 255, 255, 0.1);
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: var(--radius);
  padding: 1.25rem;
  text-align: center;
  backdrop-filter: blur(8px);
}

.stat-card strong {
  display: block;
  font-size: 1.75rem;
  font-weight: 800;
  line-height: 1.2;
}

.stat-card span { font-size: 0.85rem; opacity: 0.85; }

/* Sections */
.section {
  padding: 5rem 0;
}

.section-alt { background: var(--color-surface); }

.section-header {
  text-align: center;
  max-width: 720px;
  margin: 0 auto 3rem;
}

.section-tag {
  display: inline-block;
  color: var(--color-primary);
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  margin-bottom: 0.5rem;
}

.section-header h2 {
  font-size: clamp(1.5rem, 3vw, 2.1rem);
  font-weight: 800;
  margin: 0 0 0.75rem;
  letter-spacing: -0.02em;
}

.section-header p {
  color: var(--color-text-muted);
  margin: 0;
}

/* About */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2.5rem;
  align-items: start;
}

.about-text p { color: var(--color-text-muted); margin: 0 0 1rem; }

.feature-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: 1.5rem;
}

.feature-tags span {
  padding: 0.35rem 0.85rem;
  background: rgba(13, 110, 110, 0.08);
  color: var(--color-primary-dark);
  border-radius: 999px;
  font-size: 0.85rem;
  font-weight: 500;
}

.about-cards {
  display: grid;
  gap: 1rem;
}

.info-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1.25rem 1.5rem;
  box-shadow: var(--shadow-sm);
}

.info-card h3 {
  font-size: 1rem;
  margin: 0 0 0.35rem;
  color: var(--color-primary-dark);
}

.info-card p {
  margin: 0;
  font-size: 0.9rem;
  color: var(--color-text-muted);
}

/* Products */
.products-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}

.product-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  transition: transform 0.25s, box-shadow 0.25s;
}

.product-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}

.product-icon {
  width: 48px;
  height: 48px;
  border-radius: 12px;
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-light));
  display: grid;
  place-items: center;
  font-size: 1.4rem;
  margin-bottom: 1rem;
}

.product-card h3 {
  font-size: 1.1rem;
  margin: 0 0 0.5rem;
}

.product-card p {
  margin: 0;
  font-size: 0.9rem;
  color: var(--color-text-muted);
}

/* Safety features */
.safety-split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  align-items: center;
}

.safety-image {
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
}

.safety-list {
  display: grid;
  gap: 0.75rem;
}

.safety-item {
  display: flex;
  gap: 1rem;
  align-items: flex-start;
  padding: 1rem 1.25rem;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  transition: border-color 0.2s;
}

.safety-item:hover { border-color: var(--color-primary-light); }

.safety-num {
  flex-shrink: 0;
  width: 32px;
  height: 32px;
  border-radius: 8px;
  background: var(--color-primary);
  color: #fff;
  display: grid;
  place-items: center;
  font-size: 0.85rem;
  font-weight: 700;
}

.safety-item p { margin: 0; font-size: 0.95rem; }

/* Spec table */
.spec-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}

.spec-card img {
  width: 100%;
  max-height: 320px;
  object-fit: cover;
}

.spec-body { padding: 2rem; }

.spec-body h3 { margin: 0 0 1rem; font-size: 1.25rem; }

.spec-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
}

.spec-table th,
.spec-table td {
  padding: 0.65rem 1rem;
  text-align: left;
  border-bottom: 1px solid var(--color-border);
}

.spec-table th {
  width: 30%;
  color: var(--color-text-muted);
  font-weight: 500;
  background: var(--color-bg);
}

.spec-table tr:last-child th,
.spec-table tr:last-child td { border-bottom: none; }

/* Knowledge / SEO articles */
.articles-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.5rem;
}

.article-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
}

.article-card h3 {
  font-size: 1.05rem;
  margin: 0 0 0.75rem;
  color: var(--color-primary-dark);
}

.article-card p {
  margin: 0 0 0.75rem;
  font-size: 0.92rem;
  color: var(--color-text-muted);
}

.article-card ul {
  margin: 0;
  padding-left: 1.25rem;
  font-size: 0.92rem;
  color: var(--color-text-muted);
}

.article-card li { margin-bottom: 0.35rem; }

/* CTA */
.cta {
  background: linear-gradient(135deg, var(--color-primary-dark), var(--color-primary));
  color: #fff;
  border-radius: var(--radius-lg);
  padding: 3rem;
  text-align: center;
  margin-top: 2rem;
}

.cta h2 { margin: 0 0 0.75rem; font-size: 1.75rem; }

.cta p { opacity: 0.9; margin: 0 0 1.5rem; }

.cta-phones {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 1.5rem;
  font-size: 1.1rem;
  font-weight: 600;
}

.cta-phones a { color: #fff; }

/* Footer */
.site-footer {
  background: #0f172a;
  color: #94a3b8;
  padding: 3rem 0 1.5rem;
  font-size: 0.9rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 2rem;
  margin-bottom: 2rem;
}

.footer-brand .logo { color: #fff; margin-bottom: 0.75rem; }

.footer-brand p { margin: 0; line-height: 1.8; }

.footer-col h4 {
  color: #e2e8f0;
  font-size: 0.95rem;
  margin: 0 0 0.75rem;
}

.footer-col a {
  display: block;
  color: #94a3b8;
  margin-bottom: 0.4rem;
}

.footer-col a:hover { color: #fff; }

.footer-bottom {
  border-top: 1px solid #1e293b;
  padding-top: 1.5rem;
  text-align: center;
  font-size: 0.85rem;
}

.footer-bottom a { color: #94a3b8; }

/* Floating contact */
.float-contact {
  position: fixed;
  right: 1.25rem;
  bottom: 1.25rem;
  z-index: 90;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.float-btn {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.75rem 1.1rem;
  background: var(--color-primary);
  color: #fff !important;
  border-radius: 999px;
  box-shadow: var(--shadow-md);
  font-weight: 600;
  font-size: 0.9rem;
  transition: transform 0.2s, background 0.2s;
}

.float-btn:hover {
  background: var(--color-primary-dark);
  color: #fff !important;
  transform: scale(1.03);
}

/* Responsive */
@media (max-width: 960px) {
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .products-grid { grid-template-columns: repeat(2, 1fr); }
  .about-grid, .safety-split, .footer-grid { grid-template-columns: 1fr; }
  .articles-grid { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
  .nav-desktop, .header-phone { display: none; }
  .nav-toggle { display: block; }

  .hero { min-height: auto; }
  .hero-inner { padding: 3rem 0; }
  .stats-grid { grid-template-columns: 1fr 1fr; }
  .products-grid { grid-template-columns: 1fr; }
  .section { padding: 3.5rem 0; }
  .float-contact { right: 0.75rem; bottom: 0.75rem; }
  .float-btn span.label { display: none; }
  .float-btn { padding: 0.85rem; border-radius: 50%; width: 48px; height: 48px; justify-content: center; }
}

@media (max-width: 480px) {
  .stats-grid { grid-template-columns: 1fr; }
  .hero-actions { flex-direction: column; }
  .btn { width: 100%; }
}