/* ============================================
   WhatsApp Web Clone - 完整样式表
   所有样式均通过外部 CSS 类控制
   ============================================ */

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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  line-height: 1.5;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  color: #111827;
  background-color: #fff;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

a {
  text-decoration: none;
  color: inherit;
}

button {
  cursor: pointer;
  border: none;
  background: none;
  font-family: inherit;
}

ul {
  list-style: none;
}

h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: 1.2;
}

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

@keyframes slideInUp {
  from { opacity: 0; transform: translateY(30px); }
  to { opacity: 1; transform: translateY(0); }
}

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

.page-transition { animation: fadeIn 0.5s ease-in-out; }
.slide-in-up { animation: slideInUp 0.6s ease-out; }
.nav-slide-down { animation: slideDown 0.3s ease-out; }

/* ============================================
   Layout Utilities
   ============================================ */
.max-w-7xl { max-width: 76rem; margin-left: auto; margin-right: auto; }
.max-w-4xl { max-width: 56rem; margin-left: auto; margin-right: auto; }
.max-w-3xl { max-width: 48rem; margin-left: auto; margin-right: auto; }
.max-w-2xl { max-width: 42rem; margin-left: auto; margin-right: auto; }
.max-w-md { max-width: 28rem; }

.container-px { padding-left: 1rem; padding-right: 1rem; }
.px-4 { padding-left: 1rem; padding-right: 1rem; }
.py-3 { padding-top: 0.75rem; padding-bottom: 0.75rem; }
.py-4 { padding-top: 1rem; padding-bottom: 1rem; }
.py-6 { padding-top: 1.5rem; padding-bottom: 1.5rem; }
.py-8 { padding-top: 2rem; padding-bottom: 2rem; }
.py-12 { padding-top: 3rem; padding-bottom: 3rem; }
.py-16 { padding-top: 4rem; padding-bottom: 4rem; }
.p-6 { padding: 1.5rem; }
.p-8 { padding: 2rem; }
.mb-2 { margin-bottom: 0.5rem; }
.mb-3 { margin-bottom: 0.75rem; }
.mb-4 { margin-bottom: 1rem; }
.mb-6 { margin-bottom: 1.5rem; }
.mb-8 { margin-bottom: 2rem; }
.mb-12 { margin-bottom: 3rem; }
.mt-4 { margin-top: 1rem; }
.mt-8 { margin-top: 2rem; }
.mt-12 { margin-top: 3rem; }

.text-center { text-align: center; }
.text-left { text-align: left; }
.text-sm { font-size: 0.875rem; line-height: 1.25rem; }
.text-base { font-size: 1rem; line-height: 1.5rem; }
.text-lg { font-size: 1.125rem; line-height: 1.75rem; }
.text-xl { font-size: 1.25rem; line-height: 1.75rem; }
.text-2xl { font-size: 1.5rem; line-height: 2rem; }
.text-3xl { font-size: 1.875rem; line-height: 2.25rem; }
.text-4xl { font-size: 2.25rem; line-height: 2.5rem; }
.text-5xl { font-size: 3rem; line-height: 1.1; }

.font-medium { font-weight: 500; }
.font-semibold { font-weight: 600; }
.font-bold { font-weight: 700; }

.leading-tight { line-height: 1.25; }
.leading-relaxed { line-height: 1.625; }

/* ============================================
   Flexbox & Grid
   ============================================ */
.flex { display: flex; min-width: 0; min-height: 0; }
.inline-flex { display: inline-flex; }
.grid { display: grid; }
.hidden { display: none; }
.block { display: block; }
.inline-block { display: inline-block; }

.flex-col { flex-direction: column; }
.flex-row { flex-direction: row; }
.flex-wrap { flex-wrap: wrap; }
.flex-1 { flex: 1 1 0%; }
.flex-shrink-0 { flex-shrink: 0; }

.items-center { align-items: center; }
.items-start { align-items: start; }
.justify-center { justify-content: center; }
.justify-between { justify-content: space-between; }
.justify-end { justify-content: flex-end; }

.gap-1 { gap: 0.25rem; }
.gap-2 { gap: 0.5rem; }
.gap-3 { gap: 0.75rem; }
.gap-4 { gap: 1rem; }
.gap-6 { gap: 1.5rem; }
.gap-8 { gap: 2rem; }
.gap-12 { gap: 3rem; }

.space-y-2 > * + * { margin-top: 0.5rem; }
.space-y-3 > * + * { margin-top: 0.75rem; }
.space-y-4 > * + * { margin-top: 1rem; }
.space-y-6 > * + * { margin-top: 1.5rem; }
.space-y-8 > * + * { margin-top: 2rem; }
.space-x-1 > * + * { margin-left: 0.25rem; }
.space-x-3 > * + * { margin-left: 0.75rem; }
.space-x-4 > * + * { margin-left: 1rem; }

.grid-cols-1 { grid-template-columns: repeat(1, minmax(0, 1fr)); }
.grid-cols-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid-cols-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid-cols-4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }

/* ============================================
   Colors
   ============================================ */
.bg-white { background-color: #fff; }
.bg-gray-50 { background-color: #f9fafb; }
.bg-gray-100 { background-color: #f3f4f6; }
.bg-gray-200 { background-color: #e5e7eb; }
.bg-gray-900 { background-color: #111827; }
.bg-green-500 { background-color: #22c55e; }
.bg-blue-100 { background-color: #dbeafe; }
.bg-blue-500 { background-color: #3b82f6; }
.bg-green-100 { background-color: #dcfce7; }
.bg-purple-100 { background-color: #f3e8ff; }
.bg-purple-500 { background-color: #a855f7; }
.bg-orange-100 { background-color: #ffedd5; }
.bg-orange-500 { background-color: #f97316; }
.bg-red-100 { background-color: #fee2e2; }
.bg-red-500 { background-color: #ef4444; }
.bg-yellow-100 { background-color: #fef9c3; }
.bg-yellow-500 { background-color: #eab308; }
.bg-whatsapp { background-color: #25D366; }
.bg-whatsapp-dark { background-color: #20BA5A; }

.text-white { color: #fff; }
.text-gray-300 { color: #d1d5db; }
.text-gray-400 { color: #9ca3af; }
.text-gray-500 { color: #6b7280; }
.text-gray-600 { color: #4b5563; }
.text-gray-700 { color: #374151; }
.text-gray-900 { color: #111827; }
.text-whatsapp { color: #25D366; }

/* ============================================
   Borders & Rounded
   ============================================ */
.border { border-width: 1px; border-style: solid; }
.border-b { border-bottom-width: 1px; border-bottom-style: solid; }
.border-t { border-top-width: 1px; border-top-style: solid; }
.border-gray-100 { border-color: #f3f4f6; }
.border-gray-200 { border-color: #e5e7eb; }
.border-gray-300 { border-color: #d1d5db; }
.border-gray-800 { border-color: #1f2937; }

.rounded-full { border-radius: 9999px; }
.rounded-lg { border-radius: 0.5rem; }
.rounded-2xl { border-radius: 1rem; }
.rounded-md { border-radius: 0.375rem; }

/* ============================================
   Sizing
   ============================================ */
.w-4 { width: 1rem; }
.w-5 { width: 1.25rem; }
.w-6 { width: 1.5rem; }
.w-8 { width: 2rem; }
.w-10 { width: 2.5rem; }
.w-12 { width: 3rem; }
.w-16 { width: 4rem; }
.w-full { width: 100%; }
.h-4 { height: 1rem; }
.h-5 { height: 1.25rem; }
.h-6 { height: 1.5rem; }
.h-8 { height: 2rem; }
.h-10 { height: 2.5rem; }
.h-12 { height: 3rem; }
.h-16 { height: 4rem; }
.h-32 { height: 8rem; }
.h-48 { height: 12rem; }
.h-96 { height: 24rem; }
.min-h-screen { min-height: 100vh; }

/* ============================================
   Position & Overflow
   ============================================ */
.relative { position: relative; }
.absolute { position: absolute; }
.fixed { position: fixed; }
.sticky { position: sticky; top: 0; }
.z-50 { z-index: 50; }
.z-40 { z-index: 40; }
.inset-0 { top: 0; right: 0; bottom: 0; left: 0; }
.top-4 { top: 1rem; }
.left-4 { left: 1rem; }
.overflow-hidden { overflow: hidden; }

/* ============================================
   Shadows
   ============================================ */
.shadow-lg { box-shadow: 0 10px 15px -3px rgba(0,0,0,.1), 0 4px 6px -4px rgba(0,0,0,.1); }
.shadow-2xl { box-shadow: 0 25px 50px -12px rgba(0,0,0,.25); }

/* ============================================
   Transitions
   ============================================ */
.transition-all { transition-property: all; transition-timing-function: cubic-bezier(.4,0,.2,1); transition-duration: 150ms; }
.transition-colors { transition-property: color, background-color, border-color; transition-timing-function: cubic-bezier(.4,0,.2,1); transition-duration: 150ms; }
.transition-shadow { transition-property: box-shadow; transition-timing-function: cubic-bezier(.4,0,.2,1); transition-duration: 150ms; }
.transition-transform { transition-property: transform; transition-timing-function: cubic-bezier(.4,0,.2,1); transition-duration: 150ms; }
.transition-opacity { transition-property: opacity; transition-timing-function: cubic-bezier(.4,0,.2,1); transition-duration: 150ms; }
.duration-300 { transition-duration: 300ms; }

/* ============================================
   Navbar
   ============================================ */
.navbar {
  position: sticky;
  top: 0;
  z-index: 50;
  background: #fff;
  border-bottom: 1px solid #e5e7eb;
  animation: slideDown 0.3s ease-out;
}
.navbar-inner {
  max-width: 76rem;
  margin: 0 auto;
  padding: 0 1rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 4rem;
}
.navbar-logo {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  cursor: pointer;
  transition: opacity 0.15s;
}
.navbar-logo:hover { opacity: 0.8; }
.logo-circle {
  width: 2rem;
  height: 2rem;
  background: #25D366;
  border-radius: 9999px;
  display: flex;
  align-items: center;
  justify-content: center;
}
.logo-circle span {
  color: #fff;
  font-weight: 700;
  font-size: 1.125rem;
}
.navbar-brand {
  font-weight: 700;
  color: #111827;
}
.navbar-links {
  display: none;
  align-items: center;
  gap: 1.5rem;
}
.navbar-links a, .navbar-links span {
  color: #4b5563;
  transition: color 0.15s;
  cursor: pointer;
}
.navbar-links a:hover, .navbar-links span:hover {
  color: #25D366;
}
.navbar-links a.nav-active {
  color: #25D366;
}

/* ============================================
   Buttons
   ============================================ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  font-weight: 600;
  border-radius: 9999px;
  transition: all 0.15s;
  cursor: pointer;
  white-space: nowrap;
}
.btn-primary {
  background: #25D366;
  color: #fff;
  padding: 0.75rem 1.5rem;
}
.btn-primary:hover { background: #20BA5A; }
.btn-primary-lg {
  background: #25D366;
  color: #fff;
  padding: 0.75rem 2rem;
  font-size: 1rem;
}
.btn-primary-lg:hover { background: #20BA5A; }
.btn-outline {
  background: transparent;
  color: #374151;
  border: 1px solid #d1d5db;
  padding: 0.75rem 2rem;
  font-size: 1rem;
}
.btn-outline:hover { background: #f9fafb; }
.btn-outline-rounded {
  background: transparent;
  color: #374151;
  border: 1px solid #d1d5db;
  padding: 0.75rem 2rem;
  font-size: 1rem;
  border-radius: 9999px;
}
.btn-outline-rounded:hover { background: #f9fafb; }
.btn-ghost {
  background: transparent;
  color: #4b5563;
  padding: 0.5rem 1rem;
}
.btn-ghost:hover { color: #25D366; }
.btn-sm {
  padding: 0.5rem 1rem;
  font-size: 0.875rem;
}

/* ============================================
   Cards
   ============================================ */
.card {
  background: #fff;
  border-radius: 1rem;
  border: 1px solid #f3f4f6;
  overflow: hidden;
  transition: all 0.3s ease-in-out;
}
.card:hover {
  box-shadow: 0 10px 15px -3px rgba(0,0,0,.1), 0 4px 6px -4px rgba(0,0,0,.1);
}
.card-hover {
  transition: all 0.3s ease-in-out;
}
.card-hover:hover {
  box-shadow: 0 10px 15px -3px rgba(0,0,0,.1), 0 4px 6px -4px rgba(0,0,0,.1);
  transform: translateY(-4px);
}

/* ============================================
   Feature Card Header Colors
   ============================================ */
.feature-header {
  height: 8rem;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
}
.feature-header svg {
  width: 4rem;
  height: 4rem;
}
.feature-header-blue { background: #3b82f6; }
.feature-header-green { background: #22c55e; }
.feature-header-purple { background: #a855f7; }
.feature-header-orange { background: #f97316; }
.feature-header-red { background: #ef4444; }
.feature-header-yellow { background: #eab308; }

/* Feature header light variant (for features page) */
.feature-header-light {
  color: #374151;
}

/* ============================================
   Badge / Tag
   ============================================ */
.badge {
  display: inline-block;
  background: #25D366;
  color: #fff;
  padding: 0.25rem 0.75rem;
  border-radius: 9999px;
  font-size: 0.875rem;
  font-weight: 500;
}
.badge-category {
  display: inline-block;
  padding: 0.5rem 1rem;
  border-radius: 9999px;
  font-weight: 500;
  transition: all 0.15s;
  cursor: pointer;
}
.badge-category-active {
  background: #25D366;
  color: #fff;
}
.badge-category-inactive {
  background: #f3f4f6;
  color: #374151;
}
.badge-category-inactive:hover {
  background: #e5e7eb;
}

/* ============================================
   Feature List Items
   ============================================ */
.feature-list-item {
  display: flex;
  align-items: center;
  font-size: 0.875rem;
  color: #4b5563;
}
.feature-list-item .icon-chevron {
  width: 1rem;
  height: 1rem;
  color: #25D366;
  margin-right: 0.5rem;
  flex-shrink: 0;
}

/* ============================================
   Blog Article Card
   ============================================ */
.article-card {
  background: #fff;
  border-radius: 1rem;
  border: 1px solid #f3f4f6;
  overflow: hidden;
  transition: all 0.3s ease-in-out;
  cursor: pointer;
}
.article-card:hover {
  box-shadow: 0 10px 15px -3px rgba(0,0,0,.1), 0 4px 6px -4px rgba(0,0,0,.1);
  transform: translateY(-4px);
}
.article-image {
  position: relative;
  height: 12rem;
  overflow: hidden;
  background: #e5e7eb;
}
.article-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.3s;
}
.article-card:hover .article-image img {
  transform: scale(1.05);
}
.article-image .badge {
  position: absolute;
  top: 1rem;
  left: 1rem;
}
.article-body { padding: 1.5rem; }
.article-meta {
  display: flex;
  align-items: center;
  gap: 1rem;
  font-size: 0.875rem;
  color: #6b7280;
  padding-bottom: 1rem;
  margin-bottom: 1rem;
  border-bottom: 1px solid #f3f4f6;
}
.article-meta-item {
  display: flex;
  align-items: center;
  gap: 0.25rem;
}
.read-more {
  color: #25D366;
  font-weight: 500;
  display: inline-flex;
  align-items: center;
}
.read-more:hover { color: #20BA5A; }

/* ============================================
   FAQ / Details
   ============================================ */
.faq-item {
  background: #f9fafb;
  border-radius: 0.5rem;
  border: 1px solid #e5e7eb;
  overflow: hidden;
}
.faq-button {
  width: 100%;
  padding: 1rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-weight: 600;
  color: #111827;
  text-align: left;
  transition: background 0.15s;
  cursor: pointer;
  background: transparent;
  border: none;
  font-size: 1rem;
  font-family: inherit;
}
.faq-button:hover { background: #f3f4f6; }
.faq-answer {
  padding: 1rem 1.5rem;
  background: #fff;
  border-top: 1px solid #e5e7eb;
  color: #4b5563;
  display: none;
}
.faq-item.active .faq-answer { display: block; }
.faq-item.active .faq-chevron { transform: rotate(180deg); }
.faq-chevron {
  transition: transform 0.2s;
  flex-shrink: 0;
}

/* Details/Summary FAQ */
details.faq-details {
  background: #fff;
  border-radius: 0.5rem;
  padding: 1.5rem;
}
details.faq-details[open] summary .faq-icon { display: none; }
details.faq-details summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  cursor: pointer;
  font-weight: 600;
  color: #111827;
  list-style: none;
}
details.faq-details summary::-webkit-details-marker { display: none; }
details.faq-details p { margin-top: 1rem; color: #4b5563; }

/* ============================================
   Help Category Card
   ============================================ */
.help-card {
  background: #f9fafb;
  border-radius: 1rem;
  padding: 2rem;
}
.help-card-header {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 1.5rem;
}
.help-icon-box {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 2.5rem;
  height: 2.5rem;
  border-radius: 0.5rem;
  background: #25D366;
}
.help-icon-box svg { width: 1.5rem; height: 1.5rem; color: #fff; }
.help-article-link {
  display: block;
  padding: 0.5rem 0;
  color: #25D366;
  font-weight: 500;
  transition: color 0.15s;
}
.help-article-link:hover { color: #20BA5A; }

/* ============================================
   Privacy Point Card
   ============================================ */
.privacy-card {
  background: #f9fafb;
  border-radius: 1rem;
  padding: 2rem;
}
.privacy-card-inner {
  display: flex;
  align-items: flex-start;
  gap: 1rem;
}
.privacy-icon-box {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 3rem;
  height: 3rem;
  border-radius: 0.375rem;
  background: #25D366;
  flex-shrink: 0;
}
.privacy-icon-box svg { width: 1.5rem; height: 1.5rem; color: #fff; }

/* ============================================
   Search Input
   ============================================ */
.search-input-wrapper {
  position: relative;
  max-width: 42rem;
  margin: 0 auto;
}
.search-input-wrapper svg {
  position: absolute;
  left: 1rem;
  top: 0.875rem;
  width: 1.25rem;
  height: 1.25rem;
  color: #9ca3af;
}
.search-input {
  width: 100%;
  padding: 0.75rem 1rem 0.75rem 3rem;
  border-radius: 0.5rem;
  border: 1px solid #d1d5db;
  font-size: 1rem;
  outline: none;
  font-family: inherit;
}
.search-input:focus {
  border-color: #25D366;
  box-shadow: 0 0 0 2px rgba(37, 211, 102, 0.3);
}

/* ============================================
   Email Subscribe Input
   ============================================ */
.subscribe-input {
  flex: 1;
  padding: 0.75rem 1rem;
  border-radius: 0.5rem;
  border: 1px solid #d1d5db;
  font-size: 1rem;
  outline: none;
  font-family: inherit;
}
.subscribe-input:focus {
  border-color: #25D366;
  box-shadow: 0 0 0 2px rgba(37, 211, 102, 0.3);
}

/* ============================================
   Breadcrumb
   ============================================ */
.breadcrumb {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.875rem;
  color: #4b5563;
}
.breadcrumb a { transition: color 0.15s; }
.breadcrumb a:hover { color: #25D366; }
.breadcrumb .separator { color: #9ca3af; }
.breadcrumb .current { color: #111827; font-weight: 500; }

/* ============================================
   Prose (Blog Content)
   ============================================ */
.prose p {
  color: #374151;
  font-size: 1.125rem;
  line-height: 1.75;
  margin-bottom: 1.5rem;
  white-space: pre-wrap;
}

.prose a {
  color: #2440b3;
}
/* ============================================
   Footer
   ============================================ */
.footer {
  background: #111827;
  color: #d1d5db;
  padding: 3rem 0;
}
.footer-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 2rem;
  margin-bottom: 2rem;
  text-align: center;
}
.footer h4 {
  font-weight: 600;
  color: #fff;
  margin-bottom: 1rem;
}
.footer ul { list-style: none; }
.footer ul li { margin-bottom: 0.5rem; }
.footer ul li a {
  font-size: 0.875rem;
  color: #d1d5db;
  transition: color 0.15s;
}
.footer ul li a:hover { color: #fff; }
.footer-bottom {
  border-top: 1px solid #1f2937;
  padding-top: 2rem;
  text-align: center;
  font-size: 0.875rem;
}

/* ============================================
   Hero Gradient
   ============================================ */
.hero-gradient {
  background: linear-gradient(to bottom, #F5F5F0, #fff);
}

/* ============================================
   Mobile Menu
   ============================================ */
.mobile-menu-btn {
  display: flex;
  padding: 0.5rem;
  color: #4b5563;
  cursor: pointer;
  background: none;
  border: none;
}
.mobile-menu-overlay {
  position: fixed;
  top: 4rem;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0,0,0,0.5);
  z-index: 40;
  display: none;
}
.mobile-menu-overlay.active { display: block; }
.mobile-menu-panel {
  position: absolute;
  top: 4rem;
  left: 0;
  right: 0;
  background: #fff;
  border-bottom: 1px solid #e5e7eb;
  box-shadow: 0 10px 15px -3px rgba(0,0,0,.1);
  z-index: 50;
  display: none;
  animation: slideDown 0.2s ease-out;
}
.mobile-menu-panel.active { display: block; }
.mobile-menu-panel a, .mobile-menu-panel button {
  display: block;
  width: 100%;
  padding: 0.75rem 1rem;
  text-align: left;
  color: #374151;
  font-weight: 500;
  transition: background 0.15s;
  border: none;
  background: transparent;
  font-size: 1rem;
  font-family: inherit;
  cursor: pointer;
}
.mobile-menu-panel a:hover, .mobile-menu-panel button:hover {
  background: #f3f4f6;
}
.mobile-menu-actions {
  padding: 0.75rem 1rem;
  display: flex;
  gap: 0.5rem;
  border-top: 1px solid #f3f4f6;
}
.mobile-menu-actions .btn {
  flex: 1;
  text-align: center;
}

/* ============================================
   Line Clamp
   ============================================ */
.line-clamp-2 {
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

/* ============================================
   List disc
   ============================================ */
.list-disc { list-style-type: disc; }
.list-inside { list-style-position: inside; }

/* ============================================
   SVG Icons (inline)
   ============================================ */
.icon { display: inline-block; vertical-align: middle; }
.icon-sm { width: 1rem; height: 1rem; }
.icon-md { width: 1.25rem; height: 1.25rem; }
.icon-lg { width: 1.5rem; height: 1.5rem; }
.icon-xl { width: 4rem; height: 4rem; }

/* ============================================
   Section Patterns (extracted from inline styles)
   ============================================ */

/* Generic section spacing */
.section-py { padding-top: 6rem; padding-bottom: 6rem; }
.section-py-sm { padding-top: 2rem; padding-bottom: 2rem; }
.section-py-lg { padding-top: 6rem; padding-bottom: 6rem; }
.section-pt-12 { padding-top: 3rem; }
.section-pb-16 { padding-bottom: 4rem; }
.section-pt-8-pb-16 { padding-top: 2rem; padding-bottom: 4rem; }
.section-pb-0 { padding-bottom: 0; }

/* Section backgrounds */
.section-bg-white { background-color: #fff;}
.section-bg-gray { background-color: #f9fafb; }

/* Breadcrumb section */
.section-breadcrumb {
  padding: 1.5rem 0;
  background: #f9fafb;
  border-bottom: 1px solid #e5e7eb;
}

/* ============================================
   Typography Patterns (extracted from inline styles)
   ============================================ */

/* Page hero title */
.hero-title {
  font-size: 3rem;
  line-height: 1.1;
  font-weight: 700;
  color: #111827;
  margin-bottom: 1rem;
}

/* Blog post title (slightly smaller) */
.post-title {
  font-size: 2.5rem;
  line-height: 1.2;
  font-weight: 700;
  color: #111827;
  margin-bottom: 1.5rem;
  margin-top: 1rem;
}

/* Hero subtitle */
.hero-subtitle {
  font-size: 1.25rem;
  color: #4b5563;
}
.hero-subtitle-mb { margin-bottom: 2rem; }

/* Section heading */
.section-title {
  font-size: 2.5rem;
  font-weight: 700;
  color: #111827;
  margin-bottom: 1rem;
}
.section-title-mb-lg { margin-bottom: 4rem; text-align: center;}
.section-title-mb { margin-bottom: 1.5rem; }

/* Section subtitle */
.section-subtitle {
  font-size: 1.25rem;
  color: #4b5563;
}
.section-subtitle-mb { margin-bottom: 2rem; }

/* Card title (h3 inside cards) */
.card-title {
  font-size: 1.5rem;
  font-weight: 700;
  color: #111827;
  margin-bottom: 0.5rem;
}

/* Card title smaller variant */
.card-title-sm {
  font-size: 1.25rem;
  font-weight: 700;
  color: #111827;
  margin-bottom: 0.5rem;
}

/* Card description */
.card-desc {
  color: #4b5563;
  margin-bottom: 1.5rem;
}

/* Card detail text */
.card-detail {
  color: #374151;
  margin-bottom: 1.5rem;
  font-size: 0.875rem;
  line-height: 1.625;
}

/* Feature sub-heading */
.feature-sub-heading {
  font-weight: 600;
  color: #111827;
  margin-bottom: 0.75rem;
}

/* Article card title */
.article-title {
  font-size: 1.125rem;
  font-weight: 700;
  color: #111827;
  margin-bottom: 0.5rem;
}

/* Article card excerpt */
.article-excerpt {
  color: #4b5563;
  font-size: 0.875rem;
  margin-bottom: 1rem;
}

/* Article card footer row */
.article-footer-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.75rem;
  color: #6b7280;
}

/* ============================================
   Link Patterns (extracted from inline styles)
   ============================================ */
.link-green {
  color: #25D366;
  font-weight: 500;
}
.link-green:hover { color: #20BA5A; }

.link-green-inline {
  color: #25D366;
  font-weight: 500;
  display: inline-flex;
  align-items: center;
}
.link-green-inline:hover { color: #20BA5A; }

/* ============================================
   Layout Patterns (extracted from inline styles)
   ============================================ */

/* Centered flex with wrap */
.flex-center-wrap {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
}

/* Centered text block */
.centered-block {
  text-align: center;
}

/* Auto-centered with max-width */
.mx-auto { margin-left: auto; margin-right: auto; }

/* Margin bottom helpers */
.content-mb { margin-bottom: 1.5rem; }
.content-mb-sm { margin-bottom: 1rem; }
.content-mb-lg { margin-bottom: 2rem; }

/* ============================================
   Hero Image
   ============================================ */
.hero-image-wrapper {
  text-align: center;
  margin-top: 0;
}
@media (max-width: 767px) {
  .hero-image-wrapper {
    margin-top: 3rem;
  }
}
.hero-image {
  border-radius: 1rem;
  box-shadow: 0 25px 50px -12px rgba(0,0,0,.25);
  max-width: 32rem;
  width: 80%;
  margin: 0 auto;
  opacity: 0;
  transition: opacity 0.3s;
}

/* Lazy-load image (opacity 0, transition) */
.lazy-img {
  opacity: 0;
  transition: opacity 0.3s;
}

/* Cover image wrapper */
.cover-image-wrapper {
  border-radius: 1rem;
  overflow: hidden;
  margin-bottom: 3rem;
  width: 700px;           /* 固定宽度 700px */
  max-width: 100%;        /* 响应式最大宽度 */
  height:auto;           /* 高度自适应 */
  margin-left: auto;      /* 水平居中 */
  margin-right: auto;     /* 水平居中 */
}
.cover-image-wrapper img {
  width: 100%;
  height: 100%;           /* 高度自适应 */
  display: block;
}

/* 移动屏幕响应式调整 */
@media (max-width: 767px) {
  .cover-image-wrapper {
    width: 100%; 
  }
}
/* ============================================
   Blog Post Meta
   ============================================ */
.post-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 1.5rem;
  color: #6b7280;
  font-size: 0.875rem;
  margin-bottom: 2rem;
}

.post-share-row {
  margin-bottom: 2rem;
}

/* ============================================
   Privacy Policy Content Box
   ============================================ */
.policy-content-box {
  background: #fff;
  border-radius: 1rem;
  padding: 2rem;
}
.policy-section {
  margin-bottom: 2rem;
}
.policy-section:last-child {
  margin-bottom: 0;
}
.policy-section h3 {
  font-size: 1.5rem;
  font-weight: 700;
  color: #111827;
  margin-bottom: 1rem;
}
.policy-section p {
  color: #4b5563;
  margin-bottom: 1rem;
}
.policy-section p:last-child {
  margin-bottom: 0;
}
.policy-section ul {
  color: #4b5563;
}

/* Help card title */
.help-card-title {
  font-size: 1.5rem;
  font-weight: 700;
  color: #111827;
}

/* No result text (hidden by default) */
.no-result {
  color: #6b7280;
  display: none;
}

/* Subscribe wrapper */
.subscribe-wrapper {
  max-width: 32rem;
  margin: 0 auto;
}

/* Hero subtitle with max-width centered */
.hero-subtitle-centered {
  font-size: 1.25rem;
  color: #4b5563;
  max-width: 42rem;
  margin: 0 auto;
}

/* Icon chevron green */
.icon-chevron-green {
  color: #25D366;
  margin-right: 0.5rem;
}

/* ============================================
   Responsive
   ============================================ */
@media (min-width: 640px) {
  .sm\:px-6 { padding-left: 1.5rem; padding-right: 1.5rem; }
  .sm\:flex-row { flex-direction: row; }
}

@media (min-width: 768px) {
  .md\:flex { display: flex; }
  .md\:hidden { display: none; }
  .md\:grid-cols-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .md\:grid-cols-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .md\:grid-cols-4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
  .md\:flex-row { flex-direction: row; }
  .md\:items-center { align-items: center; }
  .md\:text-5xl { font-size: 3rem; line-height: 1.1; }
  .footer-grid { grid-template-columns: repeat(4, 1fr); }
}

@media (min-width: 1024px) {
  .lg\:px-8 { padding-left: 2rem; padding-right: 2rem; }
  .lg\:py-24 { padding-top: 6rem; padding-bottom: 6rem; }
  .lg\:grid-cols-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .lg\:grid-cols-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .lg\:text-6xl { font-size: 3.75rem; line-height: 1.1; }
  .lg\:justify-end { justify-content: flex-end; }
}

/* Mobile menu toggle: show on mobile, hide on desktop */
.mobile-menu-toggle { display: flex; }
@media (min-width: 768px) {
  .mobile-menu-toggle { display: none; }
  .navbar-links { display: flex; }
}