/* ============================================
   上海铭广信息科技有限公司 - 全局样式
   Version: 1.0.0
   ============================================ */

/* --- 1. CSS Variables (Design Tokens) --- */
:root {
  /* Colors */
  --color-primary: #1a56db;
  --color-primary-dark: #1544b0;
  --color-primary-light: #eff6ff;
  --color-secondary: #0e9f6e;
  --color-secondary-dark: #0a7d56;
  --color-accent: #f59e0b;
  --color-text-dark: #1f2937;
  --color-text: #4b5563;
  --color-text-light: #9ca3af;
  --color-bg: #f8fafc;
  --color-white: #ffffff;
  --color-border: #e5e7eb;
  --color-footer-bg: #111827;
  --color-footer-text: #d1d5db;

  /* Typography */
  --font-cn: 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --font-en: 'Inter', 'Noto Sans SC', sans-serif;
  --fw-regular: 400;
  --fw-medium: 500;
  --fw-semibold: 600;
  --fw-bold: 700;

  /* Spacing */
  --section-gap: 80px;
  --card-padding: 32px;
  --container-max: 1200px;

  /* Border Radius */
  --radius-card: 12px;
  --radius-btn: 8px;
  --radius-input: 6px;

  /* Shadows */
  --shadow-card: 0 1px 3px rgba(0,0,0,0.08), 0 1px 2px rgba(0,0,0,0.06);
  --shadow-hover: 0 10px 25px rgba(0,0,0,0.1);
  --shadow-nav: 0 2px 8px rgba(0,0,0,0.06);

  /* Transitions */
  --transition: all 0.3s ease;
}

/* --- 2. Reset & Base --- */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

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

body {
  font-family: var(--font-cn);
  color: var(--color-text);
  background-color: var(--color-bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

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

a:hover {
  color: var(--color-primary-dark);
}

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

ul, ol {
  list-style: none;
}

h1, h2, h3, h4, h5, h6 {
  color: var(--color-text-dark);
  font-weight: var(--fw-bold);
  line-height: 1.3;
}

h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; }
h3 { font-size: 1.5rem; }
h4 { font-size: 1.25rem; }

p {
  margin-bottom: 1rem;
  line-height: 1.8;
}

/* --- 3. Layout Utilities --- */
.container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 24px;
}

.section {
  padding: var(--section-gap) 0;
}

.section-sm {
  padding: 48px 0;
}

.text-center { text-align: center; }
.text-left { text-align: left; }

.flex { display: flex; }
.flex-col { flex-direction: column; }
.flex-wrap { flex-wrap: wrap; }
.items-center { align-items: center; }
.justify-center { justify-content: center; }
.justify-between { justify-content: space-between; }
.gap-16 { gap: 16px; }
.gap-24 { gap: 24px; }
.gap-32 { gap: 32px; }

.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 32px;
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
}

.grid-4 {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

/* --- 4. Section Header --- */
.section-header {
  text-align: center;
  margin-bottom: 48px;
}

.section-header h2 {
  margin-bottom: 16px;
  position: relative;
}

.section-header h2::after {
  content: '';
  display: block;
  width: 48px;
  height: 3px;
  background: var(--color-primary);
  margin: 12px auto 0;
  border-radius: 2px;
}

.section-header p {
  color: var(--color-text-light);
  font-size: 1.1rem;
  max-width: 640px;
  margin: 0 auto;
}

/* --- 5. Navigation --- */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: var(--color-white);
  transition: var(--transition);
  height: 72px;
}

.navbar.scrolled {
  box-shadow: var(--shadow-nav);
}

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

.nav-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.25rem;
  font-weight: var(--fw-bold);
  color: var(--color-text-dark);
}

.nav-logo img {
  height: 36px;
  width: auto;
}

.nav-logo span {
  color: var(--color-primary);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 4px;
}

.nav-links a {
  padding: 8px 14px;
  color: var(--color-text);
  font-size: 0.95rem;
  font-weight: var(--fw-medium);
  border-radius: var(--radius-btn);
  transition: var(--transition);
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--color-primary);
  background: var(--color-primary-light);
}

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

.nav-actions .nav-login {
  color: var(--color-text);
  font-weight: var(--fw-medium);
  padding: 8px 16px;
}

.nav-mobile-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}

.nav-mobile-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--color-text-dark);
  margin: 5px 0;
  transition: var(--transition);
}

/* --- 6. Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 28px;
  font-size: 0.95rem;
  font-weight: var(--fw-semibold);
  font-family: var(--font-cn);
  border: none;
  border-radius: var(--radius-btn);
  cursor: pointer;
  transition: var(--transition);
  text-decoration: none;
  white-space: nowrap;
}

.btn:hover {
  transform: translateY(-1px);
}

.btn-primary {
  background: var(--color-primary);
  color: var(--color-white);
}

.btn-primary:hover {
  background: var(--color-primary-dark);
  color: var(--color-white);
  box-shadow: 0 4px 12px rgba(26, 86, 219, 0.3);
}

.btn-secondary {
  background: var(--color-white);
  color: var(--color-primary);
  border: 1px solid var(--color-primary);
}

.btn-secondary:hover {
  background: var(--color-primary-light);
  color: var(--color-primary);
}

.btn-accent {
  background: var(--color-accent);
  color: var(--color-white);
}

.btn-accent:hover {
  background: #e08e09;
  color: var(--color-white);
}

.btn-success {
  background: var(--color-secondary);
  color: var(--color-white);
}

.btn-success:hover {
  background: var(--color-secondary-dark);
  color: var(--color-white);
}

.btn-lg {
  padding: 16px 36px;
  font-size: 1.05rem;
}

.btn-sm {
  padding: 8px 20px;
  font-size: 0.85rem;
}

.btn-block {
  width: 100%;
}

/* --- 7. Cards --- */
.card {
  background: var(--color-white);
  border-radius: var(--radius-card);
  box-shadow: var(--shadow-card);
  overflow: hidden;
  transition: var(--transition);
}

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

.card-img {
  width: 100%;
  height: 200px;
  object-fit: cover;
}

.card-body {
  padding: var(--card-padding);
}

.card-body h3 {
  margin-bottom: 12px;
}

.card-body p {
  color: var(--color-text);
  font-size: 0.95rem;
  margin-bottom: 16px;
}

.card-footer {
  padding: 16px var(--card-padding);
  border-top: 1px solid var(--color-border);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

/* Product Card */
.product-card {
  text-align: center;
}

.product-card .card-img {
  height: 220px;
}

.product-card .card-body h3 {
  color: var(--color-primary);
}

/* Pricing Card */
.pricing-card {
  text-align: center;
  position: relative;
  border: 2px solid var(--color-border);
}

.pricing-card.featured {
  border-color: var(--color-primary);
  transform: scale(1.02);
}

.pricing-card.featured:hover {
  transform: scale(1.02) translateY(-4px);
}

.pricing-badge {
  position: absolute;
  top: -1px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--color-accent);
  color: var(--color-white);
  padding: 4px 20px;
  font-size: 0.8rem;
  font-weight: var(--fw-semibold);
  border-radius: 0 0 8px 8px;
}

.pricing-card .card-body {
  padding: 40px var(--card-padding);
}

.pricing-card .price {
  font-size: 2.5rem;
  font-weight: var(--fw-bold);
  color: var(--color-text-dark);
  font-family: var(--font-en);
  margin: 16px 0;
}

.pricing-card .price small {
  font-size: 1rem;
  font-weight: var(--fw-regular);
  color: var(--color-text-light);
}

.pricing-card .pricing-features {
  text-align: left;
  margin: 24px 0;
}

.pricing-card .pricing-features li {
  padding: 8px 0;
  border-bottom: 1px solid var(--color-border);
  font-size: 0.9rem;
  display: flex;
  align-items: center;
  gap: 8px;
}

.pricing-card .pricing-features li::before {
  content: '\2713';
  color: var(--color-secondary);
  font-weight: bold;
}

/* Solution Card */
.solution-card .card-img {
  height: 240px;
}

/* Case Card */
.case-card .card-body {
  padding: 24px;
}

.case-card .case-tag {
  display: inline-block;
  background: var(--color-primary-light);
  color: var(--color-primary);
  padding: 4px 12px;
  border-radius: 4px;
  font-size: 0.8rem;
  font-weight: var(--fw-medium);
  margin-bottom: 12px;
}

.case-detail-link {
  display: inline-block;
  margin-top: 16px;
  color: var(--color-primary);
  font-size: 0.9rem;
  font-weight: var(--fw-semibold);
  transition: var(--transition);
}

.case-card:hover .case-detail-link {
  color: var(--color-primary-dark);
}

/* --- 8. Hero / Banner --- */
.hero {
  position: relative;
  min-height: 520px;
  display: flex;
  align-items: center;
  background: linear-gradient(135deg, #0f172a 0%, #1e3a5f 100%);
  overflow: hidden;
  margin-top: 72px;
}

.hero-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
}

.hero-bg img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.3;
}

.hero-overlay {
  position: absolute;
  inset: 0;
  /*background: linear-gradient(135deg, rgba(15,23,42,0.85) 0%, rgba(26,86,219,0.4) 100%);*/
  z-index: 1;
}

.hero-content {
  position: relative;
  z-index: 2;
  max-width: 680px;
}

.hero-content h1 {
  color: var(--color-white);
  font-size: 2.8rem;
  margin-bottom: 20px;
  line-height: 1.2;
}

.hero-content p {
  color: rgba(255,255,255,0.85);
  font-size: 1.15rem;
  margin-bottom: 32px;
  line-height: 1.8;
}

.hero-actions {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

/* Page Header (for inner pages) */
.page-header {
  background: linear-gradient(135deg, #0f172a 0%, #1e3a5f 100%);
  padding: 100px 0 60px;
  margin-top: 72px;
  text-align: center;
}

.page-header h1 {
  color: var(--color-white);
  margin-bottom: 16px;
}

.page-header p {
  color: rgba(255,255,255,0.75);
  font-size: 1.1rem;
  max-width: 600px;
  margin: 0 auto;
}

.breadcrumb {
  margin-top: 20px;
  display: flex;
  justify-content: center;
  gap: 8px;
  font-size: 0.9rem;
}

.breadcrumb a {
  color: rgba(255,255,255,0.6);
}

.breadcrumb a:hover {
  color: var(--color-white);
}

.breadcrumb span {
  color: rgba(255,255,255,0.4);
}

.breadcrumb .current {
  color: rgba(255,255,255,0.9);
}

/* --- 9. Forms --- */
.form-group {
  margin-bottom: 20px;
}

.form-group label {
  display: block;
  margin-bottom: 6px;
  font-weight: var(--fw-medium);
  color: var(--color-text-dark);
  font-size: 0.9rem;
}

.form-group label .required {
  color: #ef4444;
  margin-left: 2px;
}

.form-control {
  width: 100%;
  padding: 12px 16px;
  font-size: 0.95rem;
  font-family: var(--font-cn);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-input);
  transition: var(--transition);
  background: var(--color-white);
  color: var(--color-text-dark);
}

.form-control:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(26, 86, 219, 0.1);
}

.form-control::placeholder {
  color: var(--color-text-light);
}

textarea.form-control {
  min-height: 120px;
  resize: vertical;
}

select.form-control {
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='%239ca3af' d='M6 8L1 3h10z'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 12px center;
  padding-right: 36px;
}

.form-row {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}

.form-hint {
  font-size: 0.8rem;
  color: var(--color-text-light);
  margin-top: 4px;
}

/* --- 10. Footer --- */
.footer {
  background: var(--color-footer-bg);
  color: var(--color-footer-text);
  padding: 60px 0 0;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 48px;
  padding-bottom: 40px;
  border-bottom: 1px solid rgba(255,255,255,0.1);
}

.footer-brand p {
  color: var(--color-footer-text);
  font-size: 0.9rem;
  line-height: 1.8;
  margin-top: 16px;
}

.footer-col h4 {
  color: var(--color-white);
  font-size: 1rem;
  margin-bottom: 20px;
}

.footer-col ul li {
  margin-bottom: 10px;
}

.footer-col ul li a {
  color: var(--color-footer-text);
  font-size: 0.9rem;
  transition: var(--transition);
}

.footer-col ul li a:hover {
  color: var(--color-white);
}

.footer-bottom {
  padding: 24px 0;
  text-align: center;
  font-size: 0.85rem;
  color: rgba(255,255,255,0.5);
}

.footer-bottom a {
  color: rgba(255,255,255,0.6);
}

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

/* --- 11. Tags & Badges --- */
.tag {
  display: inline-block;
  padding: 4px 12px;
  font-size: 0.8rem;
  font-weight: var(--fw-medium);
  border-radius: 4px;
  background: var(--color-primary-light);
  color: var(--color-primary);
}

.tag-green {
  background: #ecfdf5;
  color: var(--color-secondary);
}

.tag-orange {
  background: #fffbeb;
  color: var(--color-accent);
}

/* --- 12. Stats / Counter --- */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 32px;
  text-align: center;
}

.stat-item .stat-number {
  font-size: 2.5rem;
  font-weight: var(--fw-bold);
  color: var(--color-primary);
  font-family: var(--font-en);
  line-height: 1;
}

.stat-item .stat-label {
  margin-top: 8px;
  font-size: 0.9rem;
  color: var(--color-text-light);
}

/* --- 13. CTA Section --- */
.cta-section {
  background: linear-gradient(135deg, #0f172a 0%, #1e3a5f 100%);
  padding: 64px 0;
  text-align: center;
}

.cta-section h2 {
  color: var(--color-white);
  margin-bottom: 16px;
}

.cta-section p {
  color: rgba(255,255,255,0.75);
  margin-bottom: 32px;
  max-width: 560px;
  margin-left: auto;
  margin-right: auto;
}

.cta-section .cta-actions {
  display: flex;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
}

/* --- 14. Modal --- */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.5);
  z-index: 2000;
  display: none;
  align-items: center;
  justify-content: center;
  padding: 24px;
}

.modal-overlay.active {
  display: flex;
}

.modal {
  background: var(--color-white);
  border-radius: var(--radius-card);
  max-width: 520px;
  width: 100%;
  max-height: 90vh;
  overflow-y: auto;
  box-shadow: 0 20px 60px rgba(0,0,0,0.2);
}

.modal-header {
  padding: 24px var(--card-padding);
  border-bottom: 1px solid var(--color-border);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.modal-header h3 {
  font-size: 1.25rem;
}

.modal-close {
  background: none;
  border: none;
  font-size: 1.5rem;
  cursor: pointer;
  color: var(--color-text-light);
  padding: 4px;
  line-height: 1;
}

.modal-close:hover {
  color: var(--color-text-dark);
}

.modal-body {
  padding: var(--card-padding);
}

.modal-footer {
  padding: 16px var(--card-padding);
  border-top: 1px solid var(--color-border);
  display: flex;
  justify-content: flex-end;
  gap: 12px;
}

/* --- 15. Table --- */
.table-wrapper {
  overflow-x: auto;
}

.data-table {
  width: 100%;
  border-collapse: collapse;
}

.data-table th,
.data-table td {
  padding: 14px 16px;
  text-align: left;
  border-bottom: 1px solid var(--color-border);
  font-size: 0.9rem;
}

.data-table th {
  background: var(--color-bg);
  font-weight: var(--fw-semibold);
  color: var(--color-text-dark);
}

.data-table tr:hover td {
  background: var(--color-primary-light);
}

/* --- 16. Tabs --- */
.tabs {
  display: flex;
  gap: 4px;
  border-bottom: 2px solid var(--color-border);
  margin-bottom: 32px;
}

.tab-btn {
  padding: 12px 24px;
  background: none;
  border: none;
  font-family: var(--font-cn);
  font-size: 0.95rem;
  font-weight: var(--fw-medium);
  color: var(--color-text);
  cursor: pointer;
  border-bottom: 2px solid transparent;
  margin-bottom: -2px;
  transition: var(--transition);
}

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

.tab-btn.active {
  color: var(--color-primary);
  border-bottom-color: var(--color-primary);
}

.tab-content {
  display: none;
}

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

/* --- 17. Feature List --- */
.feature-list {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.feature-item {
  display: flex;
  gap: 16px;
  padding: 24px;
  background: var(--color-white);
  border-radius: var(--radius-card);
  box-shadow: var(--shadow-card);
}

.feature-icon {
  flex-shrink: 0;
  width: 48px;
  height: 48px;
  background: var(--color-primary-light);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
}

.feature-text h4 {
  margin-bottom: 6px;
  font-size: 1rem;
}

.feature-text p {
  font-size: 0.9rem;
  color: var(--color-text-light);
  margin: 0;
}

/* --- 18. Timeline --- */
.timeline {
  position: relative;
  padding-left: 32px;
}

.timeline::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 2px;
  background: var(--color-border);
}

.timeline-item {
  position: relative;
  padding-bottom: 32px;
}

.timeline-item::before {
  content: '';
  position: absolute;
  left: -37px;
  top: 4px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--color-primary);
  border: 2px solid var(--color-white);
  box-shadow: 0 0 0 2px var(--color-primary);
}

.timeline-item h4 {
  font-size: 1rem;
  margin-bottom: 4px;
}

.timeline-item .timeline-date {
  font-size: 0.85rem;
  color: var(--color-text-light);
  margin-bottom: 8px;
}

.timeline-item p {
  font-size: 0.9rem;
  margin: 0;
}

/* --- 19. Alert / Notice --- */
.alert {
  padding: 16px 20px;
  border-radius: var(--radius-input);
  font-size: 0.9rem;
  margin-bottom: 20px;
}

.alert-info {
  background: var(--color-primary-light);
  color: var(--color-primary);
  border: 1px solid #bfdbfe;
}

.alert-success {
  background: #ecfdf5;
  color: var(--color-secondary);
  border: 1px solid #a7f3d0;
}

.alert-warning {
  background: #fffbeb;
  color: #92400e;
  border: 1px solid #fde68a;
}

/* --- 20. Auth Pages --- */
.auth-wrapper {
  min-height: calc(100vh - 72px);
  margin-top: 72px;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 40px 24px;
  background: var(--color-bg);
}

.auth-card {
  background: var(--color-white);
  border-radius: var(--radius-card);
  box-shadow: var(--shadow-card);
  padding: 48px;
  max-width: 460px;
  width: 100%;
}

.auth-card h2 {
  text-align: center;
  margin-bottom: 8px;
}

.auth-card .auth-subtitle {
  text-align: center;
  color: var(--color-text-light);
  margin-bottom: 32px;
}

.auth-card .auth-footer {
  text-align: center;
  margin-top: 24px;
  font-size: 0.9rem;
  color: var(--color-text-light);
}

/* --- 21. Legal Page --- */
.legal-content {
  max-width: 800px;
  margin: 0 auto;
  padding: 48px 24px;
}

.legal-content h2 {
  margin: 32px 0 16px;
  font-size: 1.3rem;
}

.legal-content h3 {
  margin: 24px 0 12px;
  font-size: 1.1rem;
}

.legal-content p,
.legal-content li {
  font-size: 0.95rem;
  line-height: 1.8;
  margin-bottom: 12px;
}

.legal-content ul,
.legal-content ol {
  padding-left: 24px;
  list-style: disc;
  margin-bottom: 16px;
}

.legal-content ol {
  list-style: decimal;
}

.legal-content .legal-update-date {
  color: var(--color-text-light);
  font-size: 0.9rem;
  margin-bottom: 32px;
}

/* --- 22. Download Card --- */
.download-card {
  display: flex;
  align-items: center;
  gap: 24px;
  padding: 24px;
  background: var(--color-white);
  border-radius: var(--radius-card);
  box-shadow: var(--shadow-card);
  transition: var(--transition);
}

.download-card:hover {
  box-shadow: var(--shadow-hover);
  transform: translateY(-2px);
}

.download-icon {
  flex-shrink: 0;
  width: 56px;
  height: 56px;
  background: var(--color-primary-light);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
}

.download-info {
  flex: 1;
}

.download-info h4 {
  margin-bottom: 4px;
  font-size: 1rem;
}

.download-info p {
  font-size: 0.85rem;
  color: var(--color-text-light);
  margin: 0;
}

.download-actions {
  flex-shrink: 0;
}

/* --- 23. Comparison Table --- */
.comparison-table {
  width: 100%;
  border-collapse: collapse;
  background: var(--color-white);
  border-radius: var(--radius-card);
  overflow: hidden;
  box-shadow: var(--shadow-card);
}

.comparison-table th {
  background: var(--color-primary);
  color: var(--color-white);
  padding: 16px;
  font-weight: var(--fw-semibold);
  text-align: center;
}

.comparison-table td {
  padding: 14px 16px;
  border-bottom: 1px solid var(--color-border);
  text-align: center;
  font-size: 0.9rem;
}

.comparison-table td:first-child {
  text-align: left;
  font-weight: var(--fw-medium);
}

.comparison-table tr:nth-child(even) {
  background: var(--color-bg);
}

/* --- 24. Contact Info Block --- */
.contact-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
}

.contact-item {
  text-align: center;
  padding: 32px;
  background: var(--color-white);
  border-radius: var(--radius-card);
  box-shadow: var(--shadow-card);
}

.contact-item .contact-icon {
  width: 56px;
  height: 56px;
  background: var(--color-primary-light);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 16px;
  font-size: 1.5rem;
}

.contact-item h4 {
  margin-bottom: 8px;
  font-size: 1rem;
}

.contact-item p {
  font-size: 0.9rem;
  color: var(--color-text);
  margin: 0;
}

/* --- 25. Back to Top --- */
.back-to-top {
  position: fixed;
  bottom: 32px;
  right: 32px;
  width: 44px;
  height: 44px;
  background: var(--color-primary);
  color: var(--color-white);
  border: none;
  border-radius: 50%;
  cursor: pointer;
  font-size: 1.2rem;
  display: none;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 12px rgba(26,86,219,0.3);
  transition: var(--transition);
  z-index: 999;
}

.back-to-top.visible {
  display: flex;
}

.back-to-top:hover {
  background: var(--color-primary-dark);
  transform: translateY(-2px);
}

/* --- 26. Responsive --- */
@media (max-width: 1024px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: repeat(2, 1fr); }
  .stats-grid { grid-template-columns: repeat(2, 1fr); gap: 24px; }
  .feature-list { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
  :root {
    --section-gap: 48px;
    --card-padding: 24px;
  }

  h1 { font-size: 2rem; }
  h2 { font-size: 1.5rem; }

  .nav-links { display: none; }
  .nav-mobile-toggle { display: block; }

  .nav-links.mobile-open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 72px;
    left: 0;
    right: 0;
    background: var(--color-white);
    box-shadow: var(--shadow-nav);
    padding: 16px;
    gap: 0;
  }

  .nav-links.mobile-open a {
    padding: 12px 16px;
    width: 100%;
  }

  .hero { min-height: 400px; }
  .hero-content h1 { font-size: 2rem; }

  .grid-2, .grid-3 { grid-template-columns: 1fr; }
  .grid-4 { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr; gap: 32px; }
  .contact-grid { grid-template-columns: 1fr; }
  .form-row { grid-template-columns: 1fr; }

  .pricing-card.featured { transform: none; }
  .pricing-card.featured:hover { transform: translateY(-4px); }

  .hero-actions { flex-direction: column; }
  .hero-actions .btn { width: 100%; }

  .download-card { flex-direction: column; text-align: center; }

  .cert-info { padding: 16px; }

  .auth-card { padding: 32px 24px; }
}

/* --- 27. Utility Classes --- */
.mt-0 { margin-top: 0; }
.mt-16 { margin-top: 16px; }
.mt-24 { margin-top: 24px; }
.mt-32 { margin-top: 32px; }
.mt-48 { margin-top: 48px; }
.mb-0 { margin-bottom: 0; }
.mb-16 { margin-bottom: 16px; }
.mb-24 { margin-bottom: 24px; }
.mb-32 { margin-bottom: 32px; }
.mb-48 { margin-bottom: 48px; }
.p-0 { padding: 0; }

.bg-light { background: var(--color-primary-light); }
.bg-white { background: var(--color-white); }

.text-primary { color: var(--color-primary); }
.text-secondary { color: var(--color-secondary); }
.text-muted { color: var(--color-text-light); }
.text-dark { color: var(--color-text-dark); }

.w-full { width: 100%; }
.hidden { display: none; }
.overflow-hidden { overflow: hidden; }

/* --- 27.5. Certificate Cards --- */
.cert-card {
  display: flex;
  flex-direction: column;
  padding: 0;
}

.cert-image-wrapper {
  width: 100%;
  aspect-ratio: 4 / 3;
  overflow: hidden;
  background: #f5f5f0;
  display: flex;
  align-items: center;
  justify-content: center;
}

.cert-image-wrapper img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  transition: transform 0.4s ease;
}

.cert-card:hover .cert-image-wrapper img {
  transform: scale(1.03);
}

.cert-info {
  padding: 20px 24px 24px;
  text-align: center;
}

.cert-info h4 {
  font-size: 1.1rem;
  margin-bottom: 8px;
}

.cert-info p {
  font-size: 0.85rem;
  color: var(--color-text-light);
  margin-bottom: 4px;
}

/* --- 28. Print --- */
@media print {
  .navbar, .footer, .back-to-top, .cta-section { display: none; }
  body { background: white; color: black; }
  .hero { margin-top: 0; min-height: auto; padding: 24px 0; background: none; }
  .hero-content h1 { color: black; }
  .hero-content p { color: #333; }
}