:root {
  --primary-color: #2E7D32; /* Deep Green */
  --primary-light: #4CAF50;
  --secondary-color: #81C784; /* Mint Green */
  --text-dark: #1F2937;
  --text-muted: #4B5563;
  --background-light: #F9FAFB;
  --white: #FFFFFF;
  --error: #EF4444;
  --transition: all 0.3s ease;
  --border-radius: 12px;
  --box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  font-family: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  scroll-behavior: smooth;
  font-size: 16px;
  line-height: 1.6;
  color: var(--text-dark);
}

body {
  background-color: var(--background-light);
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: 1rem;
  color: var(--text-dark);
}

p {
  margin-bottom: 1rem;
  color: var(--text-muted);
}

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

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

img {
  max-width: 100%;
  height: auto;
  border-radius: var(--border-radius);
}

.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* Header & Navigation */
header {
  background-color: var(--white);
  box-shadow: 0 1px 3px rgba(0,0,0,0.05);
  position: sticky;
  top: 0;
  z-index: 1000;
}

nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 70px;
}

.logo {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--primary-color);
  display: flex;
  align-items: center;
  gap: 0.5rem;
  white-space: nowrap;
}

.logo img {
  height: 32px;
  width: auto;
  object-fit: contain;
}

.logo span {
  color: var(--text-dark);
}

.nav-links {
  display: flex;
  gap: 2rem;
  list-style: none;
}

.nav-links a {
  font-weight: 500;
  color: var(--text-muted);
}

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

/* ==========================================================================
   🌿 现代 Glassmorphism 下拉菜单样式 (Dropdown Menu)
   ========================================================================== */
.nav-links li.dropdown {
  position: relative;
}

.dropdown-trigger {
  display: flex;
  align-items: center;
  gap: 6px;
  cursor: pointer;
  font-weight: 500 !important;
  color: var(--text-muted) !important;
  transition: var(--transition);
}

.dropdown-trigger:hover {
  color: var(--primary-color) !important;
}

.dropdown-trigger .arrow {
  font-size: 0 !important; /* Hide old solid triangle character */
  display: inline-block;
  width: 6.5px;
  height: 6.5px;
  border-bottom: 2px solid currentColor; /* Dynamic color inheritance */
  border-right: 2px solid currentColor;
  transform: rotate(45deg); /* Forms the sleek V-shaped Chevron Down */
  transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  margin-left: 6px;
  position: relative;
  top: -2.5px; /* Precision vertical centering offset */
}

/* Glassmorphism 下拉大面板 */
.dropdown-menu {
  position: absolute;
  top: calc(100% + 12px);
  left: 50%;
  transform: translateX(-50%) translateY(-12px);
  opacity: 0;
  visibility: hidden;
  width: 240px;
  max-height: 400px;
  overflow-y: auto;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  border: 1px solid rgba(255, 255, 255, 0.5);
  border-radius: 20px;
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.08);
  padding: 10px;
  display: flex;
  flex-direction: column;
  gap: 6px;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  z-index: 1002;
}

/* 极细现代滚动条 */
.dropdown-menu::-webkit-scrollbar {
  width: 5px;
}
.dropdown-menu::-webkit-scrollbar-thumb {
  background: rgba(46, 125, 50, 0.15);
  border-radius: 10px;
}

/* 菜单列表链接 */
.dropdown-menu a {
  display: flex !important;
  align-items: center;
  gap: 10px;
  padding: 10px 14px;
  color: var(--text-dark) !important;
  font-size: 0.9rem;
  text-decoration: none;
  font-weight: 500;
  border-radius: 12px;
  transition: all 0.2s ease;
}

.dropdown-menu a:hover {
  background: rgba(46, 125, 50, 0.08) !important;
  color: var(--primary-color) !important;
  transform: translateX(6px);
}

.dropdown-menu a .icon {
  display: none !important; /* Completely hide emoji icons for a minimalist list */
}

.dropdown-menu a:hover .icon {
  display: none !important;
}

/* 桌面端悬停展开 */
@media (min-width: 769px) {
  .nav-links li.dropdown:hover .dropdown-menu {
    opacity: 1;
    visibility: visible;
    transform: translateX(-50%) translateY(0);
  }
  
  .nav-links li.dropdown:hover .dropdown-trigger .arrow {
    transform: rotate(-135deg) translateY(-1px); /* Perfect Chevron Up rotation */
  }
}

/* 移动端抽屉自适应适配 */
@media (max-width: 768px) {
  .dropdown-menu {
    position: static !important;
    transform: none !important;
    opacity: 1 !important;
    visibility: visible !important;
    box-shadow: none !important;
    background: rgba(46, 125, 50, 0.03) !important;
    border: none !important;
    width: 100% !important;
    max-height: none !important;
    padding: 0 1rem !important;
    display: none !important; /* 由 JS 动态控制 toggle */
  }
  
  .nav-links li.dropdown.active .dropdown-menu {
    display: flex !important;
  }
  
  .nav-links li.dropdown.active .dropdown-trigger .arrow {
    transform: rotate(-135deg) translateY(-1px); /* Mobile Chevron Up active state */
  }
}

/* Hamburger Menu */
.hamburger {
  display: none;
  flex-direction: column;
  cursor: pointer;
  gap: 5px;
}

.hamburger span {
  width: 25px;
  height: 3px;
  background-color: var(--text-dark);
  border-radius: 3px;
  transition: var(--transition);
}

/* Hamburger Animation */
.hamburger.active span:nth-child(1) {
  transform: translateY(8px) rotate(45deg);
}

.hamburger.active span:nth-child(2) {
  opacity: 0;
}

.hamburger.active span:nth-child(3) {
  transform: translateY(-8px) rotate(-45deg);
}

/* Language Switcher */
.lang-switcher {
  position: relative;
  display: inline-block;
  margin-left: 1rem;
}

.lang-btn {
  background: none;
  border: none;
  font-family: inherit;
  font-size: 1rem;
  font-weight: 500;
  color: var(--text-muted);
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 0.25rem;
}

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

.lang-dropdown {
  position: absolute;
  top: 100%;
  right: 0;
  background-color: var(--white);
  min-width: 160px;
  box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  border-radius: 8px;
  border: 1px solid #f3f4f6;
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: var(--transition);
  z-index: 1001;
  display: flex;
  flex-direction: column;
  padding: 0.5rem 0;
  max-height: 400px;
  overflow-y: auto;
}

.lang-switcher:hover .lang-dropdown,
.lang-switcher.active .lang-dropdown {
  opacity: 1;
  visibility: visible;
  transform: translateY(5px);
}

.lang-dropdown a {
  padding: 0.5rem 1rem;
  color: var(--text-dark);
  font-size: 0.875rem;
  text-decoration: none;
  transition: background-color 0.2s;
}

.lang-dropdown a:hover {
  background-color: var(--background-light);
  color: var(--primary-color);
}

/* Buttons */
.btn {
  display: inline-block;
  padding: 0.75rem 1.5rem;
  border-radius: 9999px;
  font-weight: 600;
  text-align: center;
  cursor: pointer;
  transition: var(--transition);
  border: none;
}

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

.btn-primary:hover {
  background-color: #1B5E20;
  color: var(--white);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(46, 125, 50, 0.3);
}

/* Hero Section */
.hero {
  padding: 5rem 0;
  background: linear-gradient(135deg, #E8F5E9 0%, #C8E6C9 100%);
}

.hero-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 3rem;
}

.hero-content {
  flex: 1;
  text-align: left;
}

.hero-image {
  flex: 1;
  display: flex;
  justify-content: center;
}

.hero-image img {
  max-width: 100%;
  height: auto;
}

.hero h1 {
  font-size: 3.5rem;
  font-weight: 800;
  margin-bottom: 1.5rem;
  color: #111827;
  line-height: 1.1;
}

.hero p {
  font-size: 1.25rem;
  max-width: 600px;
  margin: 0 0 2.5rem 0;
  color: var(--text-muted);
}

.app-badges {
  display: flex;
  justify-content: flex-start;
  gap: 1rem;
  margin-top: 2rem;
}

.app-store-btn:hover {
  transform: scale(1.05);
}

.store-badge {
  background-color: #000;
  color: #fff;
  padding: 0.75rem 1.5rem;
  border-radius: 8px;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-weight: 600;
  transition: var(--transition);
}

.store-badge:hover {
  transform: scale(1.05);
  color: #fff;
}

/* Features Section */
.features {
  padding: 5rem 0;
  background-color: var(--white);
}

.section-title {
  text-align: center;
  font-size: 2.25rem;
  margin-bottom: 3rem;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
}

.feature-card {
  background: var(--white);
  padding: 2rem;
  border-radius: var(--border-radius);
  box-shadow: var(--box-shadow);
  transition: var(--transition);
  text-align: center;
  border: 1px solid #f3f4f6;
}

.feature-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
  border-color: var(--secondary-color);
}

.feature-icon {
  margin-bottom: 1.5rem;
  display: flex;
  justify-content: center;
  align-items: center;
  height: 96px; /* 固定高度，确保卡片整体对齐 */
}

.feature-icon-img {
  width: 96px;
  height: 96px;
  object-fit: contain;
  transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.feature-card:hover .feature-icon-img {
  transform: scale(1.08); /* 悬浮时微小的放大动效，增添生动感 */
}

/* How It Works Section */
.how-it-works {
  padding: 0;
  background-color: transparent;
  overflow: hidden; /* 杜绝 Full-bleed 在部分极限窄屏上产生水平方向无意义滚动条的风险 */
}

.how-it-works .section-title {
  margin: 0;
  padding-top: 3.5rem;
  padding-bottom: 3.5rem;
  background-color: #F9FAFB;
  border-top: 1px solid #EAECEF;
  border-bottom: 1px solid #EAECEF;
  
  /* 现代 CSS Full-bleed 技术：突破父限宽容器，拉伸背景至水平 100% 视口通栏，同时版心内容对齐无偏离 */
  margin-left: calc(-50vw + 50%);
  margin-right: calc(-50vw + 50%);
  padding-left: calc(50vw - 50%);
  padding-right: calc(50vw - 50%);
  
  text-align: center;
  font-size: 2.25rem;
  color: var(--text-dark);
}

.steps {
  display: flex;
  flex-direction: column;
  gap: 0; /* 移除外层 gap，使交替色带完美无缝衔接 */
}

.step {
  display: flex;
  align-items: center;
  gap: 3rem;
  
  /* 现代 CSS Full-bleed 技术：突破父限宽容器，拉伸背景至水平 100% 视口通栏，同时版心内容对齐无偏离 */
  margin-left: calc(-50vw + 50%);
  margin-right: calc(-50vw + 50%);
  padding-left: calc(50vw - 50%);
  padding-right: calc(50vw - 50%);
  
  /* 精致高雅的上下黄金内边距，呈现出宽敞、通透、高颜值的杂志版面排布 */
  padding-top: 5rem;
  padding-bottom: 5rem;
  box-sizing: border-box;
}

/* 步骤 1: 纯白分区 */
.step:nth-child(1) {
  background-color: var(--white);
}

/* 步骤 2: 淡雅青绿色通栏分区，完美匹配植物/健康生态的 Plantin 美学质感 */
.step:nth-child(2) {
  background-color: #F4FAF6;
}

/* 步骤 3: 纯白分区 */
.step:nth-child(3) {
  background-color: var(--white);
}

.step:nth-child(even) {
  flex-direction: row-reverse;
}

.step-text, .step-image {
  flex: 1;
}

.step-number {
  background: var(--primary-light);
  color: var(--white);
  width: 40px;
  height: 40px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  font-weight: bold;
  font-size: 1.25rem;
  margin-bottom: 1rem;
}

.step-image {
  display: flex;
  align-items: center;
  justify-content: center;
}

.step-image img {
  width: 100%;
  max-width: 480px;
  height: auto;
  transition: transform 0.3s ease;
}

.step-image img:hover {
  transform: translateY(-4px);
}

/* FAQ Section */
.faq-section {
  padding: 5rem 0;
  background-color: var(--white);
}

.faq-item {
  border-bottom: 1px solid #E5E7EB;
  padding: 1.5rem 0;
}

.faq-question {
  font-size: 1.125rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
  color: var(--text-dark);
}

/* Legal Pages (TOS & Privacy) */
.legal-content {
  padding: 4rem 0;
  max-width: 800px;
  margin: 0 auto;
}

.legal-content h1 {
  font-size: 2.5rem;
  margin-bottom: 2rem;
  border-bottom: 2px solid var(--primary-light);
  padding-bottom: 1rem;
}

.legal-content h2 {
  font-size: 1.75rem;
  margin-top: 2.5rem;
  margin-bottom: 1rem;
  color: var(--primary-color);
}

.legal-content ul, .legal-content ol {
  margin-bottom: 1.5rem;
  padding-left: 1.5rem;
  color: var(--text-muted);
}

.legal-content li {
  margin-bottom: 0.5rem;
}

.updated-date {
  font-style: italic;
  color: #6B7280;
  margin-bottom: 2rem;
}

/* Bottom CTA Banner - Fixed Floating Glassmorphism Style */
.bottom-cta-banner {
  position: fixed;
  bottom: 1.5rem;
  left: 0;
  width: 100%;
  z-index: 9999;
  pointer-events: none; /* Prevent blocking layout interactions underneath */
}

.bottom-cta {
  background-color: rgba(230, 244, 234, 0.96);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid rgba(255, 255, 255, 0.6);
  border-radius: 16px;
  padding: 1.25rem 2.5rem;
  margin: 0 auto;
  max-width: 1000px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
  pointer-events: auto; /* Re-enable pointer events for the banner itself */
}

.bottom-cta-content {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 2rem;
}

.bottom-cta h2 {
  font-size: 1.25rem;
  font-weight: 700;
  color: #1F2937;
  margin-bottom: 0;
  line-height: 1.4;
}

.btn-gradient {
  background: linear-gradient(90deg, #10B981 0%, #34D399 100%);
  color: #fff;
  font-size: 1rem;
  font-weight: 600;
  padding: 0.8rem 2.2rem;
  border-radius: 50px;
  border: none;
  cursor: pointer;
  white-space: nowrap;
  box-shadow: 0 4px 12px rgba(16, 185, 129, 0.25);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
  text-decoration: none;
  display: inline-block;
}

.btn-gradient:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 18px rgba(16, 185, 129, 0.35);
  color: #fff;
}

/* Footer */
footer {
  background-color: #111827;
  color: #9CA3AF;
  padding: 4rem 0 7.5rem; /* Large bottom padding to prevent overlap with sticky banner */
  margin-top: auto;
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 2rem;
  margin-bottom: 3rem;
}

.footer-col h4 {
  color: var(--white);
  margin-bottom: 1.5rem;
}

.footer-links {
  list-style: none;
}

.footer-links li {
  margin-bottom: 0.75rem;
}

.footer-links a {
  color: #9CA3AF;
}

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

.footer-bottom {
  text-align: center;
  padding-top: 2rem;
  border-top: 1px solid #374151;
}

/* Responsive */
@media (max-width: 768px) {
  .logo {
    font-size: 1.25rem;
  }
  
  .logo img {
    height: 28px;
  }

  .hero-container {
    flex-direction: column;
    text-align: center;
  }

  .hero-content {
    text-align: center;
    order: 1;
  }

  .hero-image {
    order: 2;
    margin-top: 2rem;
  }

  .hero p {
    margin: 0 auto 2.5rem;
  }

  .app-badges {
    justify-content: center;
  }

  .hero h1 {
    font-size: 2.5rem;
  }
  
  .step {
    flex-direction: column !important;
    gap: 1.5rem;
    padding-top: 3.5rem;
    padding-bottom: 3.5rem;
  }

  .how-it-works .section-title {
    padding-top: 2.5rem;
    padding-bottom: 2.5rem;
    font-size: 1.75rem; /* 移动端字号缩微，更加和谐且防折行 */
  }
  
  .hamburger {
    display: flex;
  }
  
  .nav-links {
    position: absolute;
    top: 70px;
    left: 0;
    width: 100%;
    background-color: var(--white);
    flex-direction: column;
    align-items: center;
    gap: 1.5rem;
    padding: 2rem 0;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    transform: translateY(-150%);
    opacity: 0;
    transition: var(--transition);
    z-index: 999;
  }
  
  .nav-links.active {
    transform: translateY(0);
    opacity: 1;
  }
  
  .btn {
    display: none; /* Hide top CTA on mobile if it clutters, or keep it */
  }
  
  .nav-links .btn {
    display: inline-block; /* Show it inside menu if we move it there, but here it's fine */
  }

  .lang-switcher {
    position: relative;
    margin-left: auto;
    margin-right: 1.25rem; /* Increase gap to prevent overcrowding with hamburger */
    width: auto;
    text-align: left;
    display: flex !important; /* Enable flex container for absolute vertical centering */
    align-items: center;
    height: 100%;
  }
  
  .lang-btn {
    width: auto;
    font-size: 0 !important; /* Hide long text */
    padding: 4px 0;
    background: none !important; /* Remove container background */
    border: none !important; /* Remove border */
    border-radius: 0 !important; /* Remove border radius */
    display: flex !important;
    align-items: center;
    gap: 5px;
    cursor: pointer;
    transition: all 0.2s ease;
    height: 24px;
  }

  .lang-btn::before {
    content: "";
    display: inline-block;
    width: 17px; /* Scale up slightly for solid visual presence */
    height: 17px;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%232e7d32' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Ccircle cx='12' cy='12' r='10'/%3E%3Cline x1='2' y1='12' x2='22' y2='12'/%3E%3Cpath d='M12 2a15.3 15.3 0 0 1 4 10 15.3 15.3 0 0 1-4 10 15.3 15.3 0 0 1-4-10 15.3 15.3 0 0 1 4-10z'/%3E%3C/svg%3E");
    background-size: contain;
    background-repeat: no-repeat;
    background-position: center;
  }

  .lang-btn::after {
    font-size: 12.5px !important; /* Harmonize font size with logo and hamburger */
    font-weight: 700;
    color: var(--primary-color);
    text-transform: uppercase;
    letter-spacing: 0.02em;
    line-height: 1;
    position: relative;
    top: 0.5px; /* Precision baseline translation for exact vertical alignment */
  }

  /* Seamless multi-language dynamic abbreviation injection */
  html[lang="en"] .lang-btn::after { content: "EN"; }
  html[lang="zh"] .lang-btn::after { content: "ZH"; }
  html[lang="ja"] .lang-btn::after { content: "JA"; }
  html[lang="ko"] .lang-btn::after { content: "KO"; }
  html[lang="de"] .lang-btn::after { content: "DE"; }
  html[lang="fr"] .lang-btn::after { content: "FR"; }
  html[lang="es"] .lang-btn::after { content: "ES"; }
  html[lang="it"] .lang-btn::after { content: "IT"; }
  html[lang="pt-br"] .lang-btn::after, html[lang="pt-BR"] .lang-btn::after { content: "PT"; }
  html[lang="nl"] .lang-btn::after { content: "NL"; }
  html[lang="tr"] .lang-btn::after { content: "TR"; }
  html[lang="id"] .lang-btn::after { content: "ID"; }

  .lang-dropdown {
    position: absolute !important;
    top: calc(100% + 8px) !important;
    right: 0 !important;
    left: auto !important;
    background: rgba(255, 255, 255, 0.98) !important;
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.12) !important;
    border-radius: 12px !important;
    border: 1px solid rgba(46, 125, 50, 0.1) !important;
    min-width: 140px !important;
    padding: 6px 0 !important;
    max-height: 260px !important;
    overflow-y: auto !important;
    z-index: 10001 !important;
    display: none !important;
    transform: none !important;
    opacity: 1 !important;
    visibility: visible !important;
    flex-direction: column !important;
  }
  
  .lang-switcher.active .lang-dropdown {
    display: flex !important;
  }

  .lang-dropdown a {
    padding: 8px 14px !important;
    font-size: 13px !important;
    font-weight: 500 !important;
    color: var(--text-dark) !important;
    text-align: left !important;
    background: transparent !important;
    border-radius: 0 !important;
  }

  .lang-dropdown a:hover {
    background-color: rgba(46, 125, 50, 0.05) !important;
    color: var(--primary-color) !important;
  }

  .legal-content {
    padding: 2rem 1.5rem;
  }
  
  .legal-content h1 {
    font-size: 2rem;
  }
  
  .legal-content h2 {
    font-size: 1.5rem;
  }
  
  .bottom-cta-banner {
    bottom: 1rem;
  }

  .bottom-cta {
    width: calc(100% - 2rem);
    padding: 0.85rem 1.25rem;
    border-radius: 12px;
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.1);
  }
  
  .bottom-cta-content {
    flex-direction: column;
    text-align: center;
    gap: 0.75rem;
  }

  .bottom-cta h2 {
    font-size: clamp(0.75rem, 2.5vw, 0.85rem);
    line-height: 1.3;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    width: 100%;
    letter-spacing: -0.02em;
  }
  
  .btn-gradient {
    width: 100%;
    text-align: center;
    padding: 0.65rem 0;
    font-size: 0.95rem;
  }

  footer {
    padding-bottom: 9.5rem; /* Extra padding-bottom on mobile to offset stacked floating banner */
  }
}