/* ===== CSS Variables ===== */
:root {
  --primary: #1a5f7a;
  --primary-dark: #134a61;
  --primary-light: #2a8cb0;
  --accent: #c9a227;
  --accent-light: #e8c547;
  --text: #1e293b;
  --text-muted: #64748b;
  --text-light: #94a3b8;
  --bg: #ffffff;
  --bg-alt: #f8fafc;
  --bg-dark: #0f172a;
  --border: #e2e8f0;
  --shadow: 0 4px 24px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 12px 48px rgba(0, 0, 0, 0.12);
  --radius: 12px;
  --radius-lg: 20px;
  --transition: 0.3s ease;
  --font: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

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

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

body {
  font-family: var(--font);
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
  overflow-x: hidden;
}

a {
  text-decoration: none;
  color: inherit;
  transition: color var(--transition);
}

ul {
  list-style: none;
}

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

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ===== Header ===== */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid transparent;
  transition: all var(--transition);
}

.header.scrolled {
  border-bottom-color: var(--border);
  box-shadow: var(--shadow);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 12px;
}

.logo-icon {
  width: 44px;
  height: 44px;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  color: #fff;
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  font-weight: 700;
  flex-shrink: 0;
}

.logo-text {
  display: flex;
  flex-direction: column;
  line-height: 1.3;
}

.logo-text strong {
  font-size: 16px;
  color: var(--text);
}

.logo-text small {
  font-size: 11px;
  color: var(--text-muted);
  font-weight: 400;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav-link {
  padding: 8px 16px;
  font-size: 14px;
  font-weight: 500;
  color: var(--text-muted);
  border-radius: 8px;
  transition: all var(--transition);
}

.nav-link:hover,
.nav-link.active {
  color: var(--primary);
  background: rgba(26, 95, 122, 0.08);
}

.nav-cta {
  background: var(--primary) !important;
  color: #fff !important;
}

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

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition: all var(--transition);
}

/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 28px;
  font-size: 15px;
  font-weight: 500;
  border-radius: 8px;
  border: 2px solid transparent;
  cursor: pointer;
  transition: all var(--transition);
  font-family: var(--font);
}

.btn-primary {
  background: var(--primary);
  color: #fff;
  border-color: var(--primary);
}

.btn-primary:hover {
  background: var(--primary-dark);
  border-color: var(--primary-dark);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(26, 95, 122, 0.3);
}

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

.btn-outline:hover {
  background: rgba(255, 255, 255, 0.15);
  border-color: #fff;
}

.btn-full {
  width: 100%;
}

/* ===== Hero ===== */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, #0f2d3d 0%, var(--primary) 40%, var(--primary-light) 100%);
}

.hero-bg::before {
  content: '';
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 20% 80%, rgba(201, 162, 39, 0.15) 0%, transparent 50%),
    radial-gradient(circle at 80% 20%, rgba(255, 255, 255, 0.08) 0%, transparent 40%);
}

.hero-bg::after {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.03) 1px, transparent 1px);
  background-size: 60px 60px;
}

.hero-content {
  position: relative;
  z-index: 1;
  text-align: center;
  color: #fff;
  padding: 120px 24px 80px;
}

.hero-badge {
  display: inline-block;
  padding: 6px 18px;
  background: rgba(255, 255, 255, 0.12);
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: 50px;
  font-size: 13px;
  letter-spacing: 1px;
  margin-bottom: 28px;
  backdrop-filter: blur(8px);
}

.hero-title {
  font-size: clamp(28px, 5vw, 52px);
  font-weight: 700;
  line-height: 1.3;
  margin-bottom: 20px;
  letter-spacing: 2px;
}

.hero-subtitle {
  font-size: clamp(15px, 2.5vw, 18px);
  opacity: 0.9;
  line-height: 1.8;
  margin-bottom: 40px;
  font-weight: 300;
}

.hero-actions {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: 60px;
}

.hero-stats {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 40px;
  flex-wrap: wrap;
  padding: 28px 40px;
  background: rgba(255, 255, 255, 0.1);
  border: 1px solid rgba(255, 255, 255, 0.15);
  border-radius: var(--radius-lg);
  backdrop-filter: blur(12px);
  max-width: 600px;
  margin: 0 auto;
}

.stat-item {
  text-align: center;
}

.stat-num {
  display: block;
  font-size: 32px;
  font-weight: 700;
  line-height: 1;
}

.stat-num small {
  font-size: 16px;
  font-weight: 400;
}

.stat-label {
  display: block;
  font-size: 13px;
  opacity: 0.75;
  margin-top: 6px;
}

.stat-divider {
  width: 1px;
  height: 40px;
  background: rgba(255, 255, 255, 0.2);
}

.hero-scroll {
  position: absolute;
  bottom: 32px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  color: rgba(255, 255, 255, 0.6);
  font-size: 12px;
  z-index: 1;
}

.scroll-arrow {
  width: 20px;
  height: 20px;
  border-right: 2px solid rgba(255, 255, 255, 0.5);
  border-bottom: 2px solid rgba(255, 255, 255, 0.5);
  transform: rotate(45deg);
  animation: bounce 2s infinite;
}

@keyframes bounce {
  0%, 100% { transform: rotate(45deg) translateY(0); }
  50% { transform: rotate(45deg) translateY(6px); }
}

/* ===== Sections ===== */
.section {
  padding: 100px 0;
}

.section:nth-child(even) {
  background: var(--bg-alt);
}

.section-header {
  text-align: center;
  margin-bottom: 60px;
}

.section-tag {
  display: inline-block;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 3px;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 12px;
}

.section-title {
  font-size: clamp(28px, 4vw, 36px);
  font-weight: 700;
  color: var(--text);
  margin-bottom: 16px;
}

.section-desc {
  font-size: 16px;
  color: var(--text-muted);
  max-width: 560px;
  margin: 0 auto;
}

/* ===== About ===== */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: start;
}

.about-content p {
  color: var(--text-muted);
  margin-bottom: 16px;
  font-size: 15px;
}

.about-content p strong {
  color: var(--text);
}

.about-highlights {
  margin-top: 32px;
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.highlight-item {
  display: flex;
  gap: 16px;
  align-items: flex-start;
  padding: 20px;
  background: var(--bg);
  border-radius: var(--radius);
  border: 1px solid var(--border);
  transition: all var(--transition);
}

.highlight-item:hover {
  border-color: var(--primary-light);
  box-shadow: var(--shadow);
  transform: translateX(4px);
}

.highlight-icon {
  font-size: 24px;
  flex-shrink: 0;
}

.highlight-item h4 {
  font-size: 15px;
  margin-bottom: 4px;
  color: var(--text);
}

.highlight-item p {
  font-size: 13px;
  color: var(--text-light);
  margin: 0;
}

.about-card {
  background: var(--bg);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-lg);
  overflow: hidden;
}

.about-card-header {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 16px 24px;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  color: #fff;
  font-size: 14px;
  font-weight: 500;
}

.card-dot {
  width: 10px;
  height: 10px;
  background: var(--accent);
  border-radius: 50%;
}

.about-info-list {
  padding: 8px 0;
}

.about-info-list li {
  display: flex;
  flex-direction: column;
  padding: 14px 24px;
  border-bottom: 1px solid var(--border);
  gap: 4px;
}

.about-info-list li:last-child {
  border-bottom: none;
}

.info-label {
  font-size: 12px;
  color: var(--text-light);
  font-weight: 500;
}

.info-value {
  font-size: 14px;
  color: var(--text);
  font-weight: 500;
}

/* ===== Services ===== */
.services-tabs {
  display: flex;
  justify-content: center;
  gap: 8px;
  margin-bottom: 40px;
  flex-wrap: wrap;
}

.tab-btn {
  padding: 10px 28px;
  font-size: 14px;
  font-weight: 500;
  font-family: var(--font);
  border: 2px solid var(--border);
  background: var(--bg);
  color: var(--text-muted);
  border-radius: 50px;
  cursor: pointer;
  transition: all var(--transition);
}

.tab-btn:hover {
  border-color: var(--primary-light);
  color: var(--primary);
}

.tab-btn.active {
  background: var(--primary);
  border-color: var(--primary);
  color: #fff;
}

.tab-content {
  display: none;
  animation: fadeIn 0.4s ease;
}

.tab-content.active {
  display: block;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

.services-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 24px;
}

.service-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
  transition: all var(--transition);
}

.service-card:hover {
  border-color: var(--primary-light);
  box-shadow: var(--shadow);
  transform: translateY(-4px);
}

.service-icon {
  font-size: 32px;
  margin-bottom: 16px;
}

.service-card h3 {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 10px;
  color: var(--text);
}

.service-card p {
  font-size: 13px;
  color: var(--text-muted);
  line-height: 1.7;
}

/* License tab */
.license-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 32px;
  align-items: start;
}

.license-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 32px;
}

.license-badge {
  display: inline-block;
  padding: 4px 14px;
  background: rgba(201, 162, 39, 0.15);
  color: var(--accent);
  font-size: 12px;
  font-weight: 600;
  border-radius: 50px;
  margin-bottom: 12px;
}

.license-note {
  font-size: 13px;
  color: var(--text-light);
  margin-bottom: 24px;
}

.license-list {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.license-list li {
  display: flex;
  gap: 14px;
  align-items: flex-start;
}

.license-icon {
  width: 28px;
  height: 28px;
  background: rgba(26, 95, 122, 0.1);
  color: var(--primary);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 13px;
  font-weight: 700;
  flex-shrink: 0;
}

.license-list strong {
  display: block;
  font-size: 14px;
  margin-bottom: 4px;
}

.license-list p {
  font-size: 13px;
  color: var(--text-muted);
}

.license-info {
  padding: 32px;
}

.license-info h3 {
  font-size: 22px;
  margin-bottom: 16px;
}

.license-info p {
  font-size: 14px;
  color: var(--text-muted);
  line-height: 1.8;
  margin-bottom: 24px;
}

.gsxt-link {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 14px 24px;
  background: var(--primary);
  color: #fff;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 500;
  transition: all var(--transition);
}

.gsxt-link:hover {
  background: var(--primary-dark);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(26, 95, 122, 0.3);
}

.gsxt-link .arrow {
  transition: transform var(--transition);
}

.gsxt-link:hover .arrow {
  transform: translateX(4px);
}

/* ===== Advantages ===== */
.advantages {
  background: linear-gradient(135deg, var(--bg-dark) 0%, #1a3a4a 100%);
  color: #fff;
}

.advantages .section-tag {
  color: var(--accent-light);
}

.advantages .section-title {
  color: #fff;
}

.advantages .section-desc {
  color: rgba(255, 255, 255, 0.7);
}

.advantages-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 24px;
}

.advantage-card {
  padding: 32px;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--radius);
  transition: all var(--transition);
}

.advantage-card:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: rgba(201, 162, 39, 0.4);
  transform: translateY(-4px);
}

.advantage-num {
  font-size: 36px;
  font-weight: 700;
  color: var(--accent);
  opacity: 0.6;
  margin-bottom: 16px;
  line-height: 1;
}

.advantage-card h3 {
  font-size: 18px;
  margin-bottom: 12px;
}

.advantage-card p {
  font-size: 14px;
  color: rgba(255, 255, 255, 0.7);
  line-height: 1.7;
}

/* ===== Company Info ===== */
.company-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow);
}

.company-card-title {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 24px 32px;
  background: linear-gradient(135deg, #fdf6e3, #fef9ef);
  border-bottom: 2px solid var(--accent);
}

.license-seal {
  width: 52px;
  height: 52px;
  background: linear-gradient(135deg, #c0392b, #e74c3c);
  color: #fff;
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 22px;
  font-weight: 700;
  flex-shrink: 0;
  box-shadow: 0 4px 12px rgba(192, 57, 43, 0.3);
}

.company-card-title h3 {
  font-size: 18px;
  color: var(--text);
}

.company-card-title p {
  font-size: 13px;
  color: var(--text-muted);
}

.company-info-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0;
  padding: 8px 0;
}

.company-info-item {
  display: flex;
  flex-direction: column;
  padding: 16px 32px;
  border-bottom: 1px solid var(--border);
  gap: 6px;
}

.company-info-item.full {
  grid-column: 1 / -1;
}

.company-info-item label {
  font-size: 12px;
  color: var(--text-light);
  font-weight: 500;
  letter-spacing: 1px;
}

.company-info-item span {
  font-size: 14px;
  color: var(--text);
  font-weight: 500;
}

.scope-text {
  font-weight: 400 !important;
  font-size: 13px !important;
  color: var(--text-muted) !important;
  line-height: 1.8;
}

.scope-text strong {
  color: var(--text);
}

.company-footer-note {
  padding: 20px 32px;
  background: var(--bg-alt);
  border-top: 1px solid var(--border);
}

.company-footer-note p {
  font-size: 12px;
  color: var(--text-light);
  margin-bottom: 4px;
}

.company-footer-note a {
  color: var(--primary);
}

.company-footer-note a:hover {
  text-decoration: underline;
}

/* ===== Contact ===== */
.service-hotline {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 40px;
  padding: 36px 40px;
  margin-bottom: 48px;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  border-radius: var(--radius-lg);
  color: #fff;
  box-shadow: var(--shadow-lg);
}

.service-hotline-label {
  display: inline-block;
  padding: 4px 14px;
  margin-bottom: 12px;
  background: rgba(255, 255, 255, 0.15);
  border: 1px solid rgba(255, 255, 255, 0.25);
  border-radius: 50px;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 1px;
}

.service-hotline-title {
  font-size: 22px;
  font-weight: 700;
  margin-bottom: 14px;
  line-height: 1.4;
}

.service-hotline-desc {
  font-size: 14px;
  line-height: 1.8;
  color: rgba(255, 255, 255, 0.88);
  margin-bottom: 20px;
  max-width: 560px;
}

.service-hotline-desc strong {
  color: #fff;
}

.service-hotline-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.service-hotline-tags span {
  padding: 6px 14px;
  background: rgba(255, 255, 255, 0.12);
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: 50px;
  font-size: 12px;
}

.service-hotline-action {
  flex-shrink: 0;
  text-align: center;
  padding: 28px 36px;
  background: rgba(255, 255, 255, 0.12);
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: var(--radius);
  backdrop-filter: blur(8px);
}

.service-hotline-phone-label {
  display: block;
  font-size: 13px;
  color: rgba(255, 255, 255, 0.75);
  margin-bottom: 8px;
}

.service-hotline-phone {
  display: block;
  font-size: 32px;
  font-weight: 700;
  color: #fff;
  letter-spacing: 2px;
  margin-bottom: 10px;
  transition: all var(--transition);
}

.service-hotline-phone:hover {
  color: var(--accent-light);
  transform: scale(1.03);
}

.service-hotline-time {
  font-size: 12px;
  color: rgba(255, 255, 255, 0.65);
}

.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: 48px;
  align-items: start;
}

.contact-info {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.contact-item {
  display: flex;
  gap: 16px;
  align-items: flex-start;
  padding: 20px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: all var(--transition);
}

.contact-item:hover {
  border-color: var(--primary-light);
  box-shadow: var(--shadow);
}

.contact-icon {
  font-size: 24px;
  flex-shrink: 0;
}

.contact-item h4 {
  font-size: 14px;
  color: var(--text-light);
  font-weight: 500;
  margin-bottom: 4px;
}

.contact-item p {
  font-size: 15px;
  color: var(--text);
  font-weight: 500;
}

.contact-item small {
  display: block;
  margin-top: 6px;
  font-size: 12px;
  color: var(--text-light);
  font-weight: 400;
  line-height: 1.5;
}

.contact-item-highlight {
  border-color: var(--primary-light);
  background: rgba(26, 95, 122, 0.04);
}

.contact-phone-link {
  font-size: 20px;
  font-weight: 700;
  color: var(--primary);
  letter-spacing: 1px;
}

.contact-phone-link:hover {
  color: var(--primary-dark);
}

.contact-form-wrapper {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 36px;
  box-shadow: var(--shadow);
}

.contact-form-wrapper h3 {
  font-size: 20px;
  margin-bottom: 8px;
}

.form-desc {
  font-size: 14px;
  color: var(--text-muted);
  margin-bottom: 28px;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.form-group {
  margin-bottom: 20px;
}

.form-group label {
  display: block;
  font-size: 13px;
  font-weight: 500;
  color: var(--text-muted);
  margin-bottom: 8px;
}

.form-group input,
.form-group select,
.form-group textarea {
  width: 100%;
  padding: 12px 16px;
  font-size: 14px;
  font-family: var(--font);
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--bg-alt);
  color: var(--text);
  transition: all var(--transition);
  outline: none;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
  border-color: var(--primary);
  background: var(--bg);
  box-shadow: 0 0 0 3px rgba(26, 95, 122, 0.1);
}

.form-group textarea {
  resize: vertical;
  min-height: 100px;
}

/* ===== Footer ===== */
.footer {
  background: var(--bg-dark);
  color: rgba(255, 255, 255, 0.7);
  padding: 60px 0 0;
}

.footer-top {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 40px;
  padding-bottom: 40px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-brand p {
  margin-top: 16px;
  font-size: 14px;
  color: rgba(255, 255, 255, 0.5);
}

.footer .logo-text strong {
  color: #fff;
}

.footer .logo-text small {
  color: rgba(255, 255, 255, 0.5);
}

.footer-links h4,
.footer-contact h4 {
  font-size: 14px;
  color: #fff;
  margin-bottom: 16px;
  font-weight: 600;
}

.footer-links ul {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer-links a {
  font-size: 13px;
  color: rgba(255, 255, 255, 0.6);
  transition: color var(--transition);
}

.footer-links a:hover {
  color: var(--accent-light);
}

.footer-contact p {
  font-size: 13px;
  margin-bottom: 8px;
}

.footer-contact a {
  color: var(--accent-light);
  font-weight: 600;
}

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

.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 20px 0;
  flex-wrap: wrap;
  gap: 12px;
}

.footer-bottom p {
  font-size: 12px;
  color: rgba(255, 255, 255, 0.4);
}

.footer-bottom a {
  color: rgba(255, 255, 255, 0.5);
}

.footer-bottom a:hover {
  color: var(--accent-light);
}

.footer-beian {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}

.footer-divider {
  color: rgba(255, 255, 255, 0.2);
}

/* ===== Back to Top ===== */
.back-to-top {
  position: fixed;
  bottom: 32px;
  right: 32px;
  width: 44px;
  height: 44px;
  background: var(--primary);
  color: #fff;
  border: none;
  border-radius: 50%;
  font-size: 18px;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition);
  box-shadow: var(--shadow);
  z-index: 999;
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
}

.back-to-top:hover {
  background: var(--primary-dark);
  transform: translateY(-4px);
}

/* ===== Responsive ===== */
@media (max-width: 1024px) {
  .about-grid,
  .contact-grid,
  .license-content {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .service-hotline {
    flex-direction: column;
    text-align: center;
    padding: 28px 24px;
  }

  .service-hotline-desc {
    max-width: none;
  }

  .service-hotline-tags {
    justify-content: center;
  }

  .service-hotline-action {
    width: 100%;
    padding: 24px;
  }

  .footer-top {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 768px) {
  .nav-toggle {
    display: flex;
  }

  .nav-menu {
    position: fixed;
    top: 72px;
    left: 0;
    right: 0;
    background: var(--bg);
    flex-direction: column;
    padding: 16px;
    gap: 4px;
    border-bottom: 1px solid var(--border);
    box-shadow: var(--shadow);
    transform: translateY(-120%);
    opacity: 0;
    transition: all var(--transition);
    pointer-events: none;
  }

  .nav-menu.open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: all;
  }

  .nav-link {
    width: 100%;
    text-align: center;
    padding: 12px;
  }

  .section {
    padding: 70px 0;
  }

  .hero-stats {
    gap: 24px;
    padding: 20px 24px;
  }

  .stat-divider {
    display: none;
  }

  .company-info-grid {
    grid-template-columns: 1fr;
  }

  .form-row {
    grid-template-columns: 1fr;
  }

  .footer-top {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .footer-bottom {
    flex-direction: column;
    text-align: center;
  }
}

@media (max-width: 480px) {
  .hero-content {
    padding: 100px 16px 60px;
  }

  .hero-actions {
    flex-direction: column;
    align-items: center;
  }

  .btn {
    width: 100%;
    max-width: 280px;
  }

  .contact-form-wrapper {
    padding: 24px;
  }
}