/* ==========================================================================
   全局基础样式 + 通用组件
   ========================================================================== */

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

html { scroll-behavior: smooth; scroll-padding-top: calc(var(--nav-height) + 16px); overflow-x: clip; }

body {
  font-family: var(--font-sans);
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: clip;
  max-width: 100%;
}

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

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

/* 布局容器 */
.container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--space-lg);
}

.section { padding: var(--space-3xl) 0; }
.section-alt { background: var(--color-bg-alt); }

.section-header {
  text-align: center;
  margin-bottom: var(--space-2xl);
}
.section-header h2 {
  font-size: clamp(1.5rem, 4vw, 2rem);
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: var(--space-sm);
}
.section-header .section-subtitle {
  font-size: 1rem;
  color: var(--color-text-secondary);
  max-width: 600px;
  margin: 0 auto;
}
.section-header .section-tag {
  display: inline-block;
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  color: var(--color-accent-dark);
  text-transform: uppercase;
  margin-bottom: var(--space-sm);
}

/* 按钮 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  border: none;
  cursor: pointer;
  font-size: 0.95rem;
  font-weight: 600;
  font-family: inherit;
  border-radius: var(--radius-md);
  padding: 12px 28px;
  transition: all var(--transition-base);
  white-space: nowrap;
  text-decoration: none;
}
.btn-primary {
  background: var(--color-primary);
  color: #fff;
  box-shadow: var(--shadow-primary);
}
.btn-primary:hover {
  background: var(--color-primary-hover);
  color: #fff;
  transform: translateY(-1px);
}
.btn-outline {
  background: transparent;
  color: var(--color-primary);
  border: 2px solid var(--color-primary);
}
.btn-outline:hover {
  background: var(--color-primary-light);
  color: var(--color-primary-dark);
}
.btn-accent {
  background: var(--color-accent);
  color: #fff;
}
.btn-accent:hover {
  background: var(--color-accent-dark);
  color: #fff;
}
.btn-lg { font-size: 1.05rem; padding: 14px 36px; }

/* 导航栏 */
.navbar {
  position: sticky;
  top: 0;
  z-index: 1000;
  height: var(--nav-height);
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
  transition: box-shadow var(--transition-base);
}
.navbar.scrolled { box-shadow: var(--shadow-sm); }
.navbar-inner {
  max-width: var(--container-max);
  height: 100%;
  margin: 0 auto;
  padding: 0 var(--space-lg);
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.navbar-brand {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  text-decoration: none;
}
.navbar-brand .brand-logo {
  width: 36px;
  height: 41px;
  flex-shrink: 0;
  border-radius: var(--radius-md);
  object-fit: contain;
  background: #006C35;
}
.navbar-brand .brand-text {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--color-primary);
  letter-spacing: 0.02em;
  line-height: 1.2;
  position: relative;
  top: 3px;
}
.navbar-brand .brand-text .brand-en {
  font-size: 0.65rem;
  font-weight: 500;
  color: var(--color-text-tertiary);
  letter-spacing: 0.08em;
  display: block;
  margin-top: -2px;
  line-height: 1.2;
}
.navbar-links {
  display: flex;
  align-items: center;
  gap: var(--space-lg);
  list-style: none;
}
.navbar-links a {
  color: var(--color-text);
  font-size: 0.95rem;
  font-weight: 500;
  padding: var(--space-xs) 0;
  position: relative;
  transition: color var(--transition-fast);
}
.navbar-links a::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--color-accent);
  transition: width var(--transition-base);
}
.navbar-links a:hover,
.navbar-links a.active {
  color: var(--color-primary);
}
.navbar-links a:hover::after,
.navbar-links a.active::after { width: 100%; }
.navbar-actions {
  display: flex;
  align-items: center;
  gap: var(--space-md);
}
.lang-toggle {
  border: 1px solid var(--color-border);
  background: var(--color-bg);
  color: var(--color-text-secondary);
  border-radius: var(--radius-full);
  padding: 6px 14px;
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  font-family: inherit;
  transition: all var(--transition-fast);
}
.lang-toggle:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
}

/* 移动端汉堡按钮 */
.navbar-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--space-xs);
}
.navbar-toggle span {
  width: 24px;
  height: 2px;
  background: var(--color-text);
  border-radius: 2px;
  transition: all var(--transition-base);
}
.navbar-toggle.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.navbar-toggle.open span:nth-child(2) { opacity: 0; }
.navbar-toggle.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* 移动端导航 */
@media (max-width: 768px) {
  .navbar-toggle { display: flex; }
  .navbar-links {
    position: fixed;
    top: var(--nav-height);
    left: 0;
    right: 0;
    flex-direction: column;
    background: var(--color-bg);
    border-bottom: 1px solid var(--color-border);
    padding: var(--space-md) var(--space-lg);
    gap: var(--space-md);
    transform: translateY(-100%);
    opacity: 0;
    pointer-events: none;
    transition: all var(--transition-base);
    box-shadow: var(--shadow-md);
  }
  .navbar-links.open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
  }
  .navbar-links a { width: 100%; padding: var(--space-md) 0; min-height: 44px; display: flex; align-items: center; }
}

/* Footer */
.footer {
  background: var(--color-bg-dark);
  color: #C8D6CE;
  padding: var(--space-2xl) 0 var(--space-lg);
}
.footer-inner {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--space-lg);
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr;
  gap: var(--space-xl);
  margin-bottom: var(--space-xl);
}
.footer-brand .brand-text {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--color-accent);
  margin-bottom: var(--space-sm);
}
.footer-brand p {
  font-size: 0.875rem;
  color: #8FA89A;
  line-height: 1.7;
  max-width: 320px;
}
.footer-col h4 {
  font-size: 0.9rem;
  font-weight: 600;
  color: #fff;
  margin-bottom: var(--space-md);
}
.footer-col ul { list-style: none; }
.footer-col li { margin-bottom: var(--space-sm); }
.footer-col a {
  color: #C8D6CE;
  font-size: 0.875rem;
  transition: color var(--transition-fast);
}
.footer-col a:hover { color: var(--color-accent); }
.footer-contact-item {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  font-size: 0.875rem;
  color: #C8D6CE;
  margin-bottom: var(--space-sm);
}
.footer-contact-item svg { width: 16px; height: 16px; flex-shrink: 0; color: var(--color-accent); }
.footer-contact-item a { color: #C8D6CE; text-decoration: none; transition: color var(--transition-fast); }
.footer-contact-item a:hover { color: var(--color-accent); }
.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: var(--space-lg);
  text-align: center;
  font-size: 0.8rem;
  color: #8FA89A;
}
@media (max-width: 768px) {
  .footer-grid { grid-template-columns: 1fr; gap: var(--space-lg); }
  /* 间距分级压缩 */
  .section { padding: var(--space-2xl) 0; }
  .section-header { margin-bottom: var(--space-xl); }
  .footer { padding: var(--space-xl) 0 var(--space-lg); }
  /* 触摸目标达标 44px */
  .lang-toggle { min-height: 44px; padding: 8px 16px; display: inline-flex; align-items: center; }
  .navbar-toggle { min-width: 44px; min-height: 44px; }
  /* 品牌区域移动端缩放 */
  .navbar-brand .brand-logo { width: 32px; height: 36px; }
  .navbar-brand .brand-text { font-size: 1rem; }
  .navbar-brand .brand-text .brand-en { font-size: 0.58rem; }
}

@media (max-width: 480px) {
  .section { padding: var(--space-xl) 0; }
  .section-header { margin-bottom: var(--space-lg); }
  .container, .navbar-inner, .footer-inner, .stats-grid, .hero-inner {
    padding-left: var(--space-md); padding-right: var(--space-md);
  }
  /* 品牌区域小屏进一步缩放 */
  .navbar-brand .brand-logo { width: 28px; height: 32px; }
  .navbar-brand .brand-text { font-size: 0.88rem; top: 2px; }
  .navbar-brand .brand-text .brand-en { font-size: 0.52rem; }
  .navbar-brand { gap: 6px; }
  /* 统计数据紧凑 */
  .stats-grid { padding: var(--space-lg) var(--space-md); gap: var(--space-md); }
  .stat-num { font-size: 1.3rem; }
  .stat-label { font-size: 0.78rem; }
  /* 按钮紧凑 */
  .btn { padding: 10px 20px; font-size: 0.88rem; }
  .btn-lg { padding: 12px 28px; font-size: 0.95rem; }
  /* 聊天浮窗适配 */
  .chat-fab { width: 50px; height: 50px; bottom: 16px; right: 16px; }
  .chat-fab svg { width: 24px; height: 24px; }
  .chat-popup { bottom: 76px; right: 12px; left: 12px; }
  .chat-container.floating { width: 100%; height: 60vh; max-height: 500px; }
}

/* 触摸目标达标 44px（全局） */
.expand-trigger { min-height: 44px; display: inline-flex; align-items: center; }