/* ==========================================
   老人帮 - 全局通用样式 (lb_common.css)
   配色系统 + 字体规范 + 通用组件
   ========================================== */

/* === CSS 变量定义 === */
:root {
  /* 配色系统 - 暖色调 */
  --color-primary: #E8613A;
  --color-primary-dark: #D4502B;
  --color-primary-light: #FFF0EC;
  --color-secondary: #F5A623;
  --color-secondary-light: #FFF8E8;
  --color-accent: #27AE60;
  --color-info: #3498DB;
  
  /* 文字颜色 */
  --color-text: #2D3436;
  --color-text-secondary: #636E72;
  --color-text-light: #B2BEC3;
  
  /* 背景色 */
  --color-bg: #FAFAFA;
  --color-bg-warm: #FDF8F5;
  --color-card: #FFFFFF;
  
  /* 渐变 */
  --gradient-primary: linear-gradient(135deg, #E8613A 0%, #F5A623 100%);
  --gradient-hero: linear-gradient(135deg, #E8613A 0%, #F2994A 50%, #F5A623 100%);
  --gradient-warm: linear-gradient(180deg, #FDF8F5 0%, #FFFFFF 100%);
  
  /* 字体系统 */
  --font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
  --font-size-xs: 14px;
  --font-size-sm: 16px;
  --font-size-body: 18px;
  --font-size-lg: 20px;
  --font-size-h3: 20px;
  --font-size-h2: 24px;
  --font-size-h1: 32px;
  --font-size-display: 40px;
  --line-height: 1.8;
  --letter-spacing: 0.3px;
  
  /* 间距 */
  --space-xs: 8px;
  --space-sm: 12px;
  --space-md: 16px;
  --space-lg: 24px;
  --space-xl: 32px;
  --space-2xl: 48px;
  --space-3xl: 64px;
  
  /* 圆角 */
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --radius-full: 9999px;
  
  /* 阴影 */
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.04);
  --shadow-card: 0 4px 16px rgba(0, 0, 0, 0.06);
  --shadow-hover: 0 8px 32px rgba(0, 0, 0, 0.10);
  --shadow-elevated: 0 12px 40px rgba(0, 0, 0, 0.14);
  
  /* 过渡 */
  --transition-fast: all 0.15s ease;
  --transition: all 0.25s ease;
  --transition-slow: all 0.4s ease;
}

/* === 全局字体基础 === */
body {
  font-family: var(--font-family) !important;
  font-size: var(--font-size-body) !important;
  line-height: var(--line-height) !important;
  color: var(--color-text) !important;
  letter-spacing: var(--letter-spacing);
  background-color: var(--color-bg) !important;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* === 标题层级 === */
h1, .h1 { font-size: var(--font-size-h1) !important; font-weight: 700; line-height: 1.3; margin-bottom: var(--space-lg); color: var(--color-text); }
h2, .h2 { font-size: var(--font-size-h2) !important; font-weight: 700; line-height: 1.4; margin-bottom: var(--space-md); color: var(--color-text); }
h3, .h3 { font-size: var(--font-size-h3) !important; font-weight: 600; line-height: 1.5; margin-bottom: var(--space-sm); color: var(--color-text); }

p {
  margin-bottom: var(--space-lg);
  line-height: var(--line-height);
}

/* === 通用按钮样式 === */
.lb-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 28px;
  font-size: var(--font-size-sm);
  font-weight: 600;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: var(--transition);
  text-decoration: none;
  border: none;
  line-height: 1.4;
}

.lb-btn-primary {
  background: var(--color-primary);
  color: #FFFFFF;
  box-shadow: 0 4px 12px rgba(232, 97, 58, 0.3);
}

.lb-btn-primary:hover {
  background: var(--color-primary-dark);
  transform: translateY(-2px) scale(1.02);
  box-shadow: 0 6px 20px rgba(232, 97, 58, 0.4);
  color: #FFFFFF;
  text-decoration: none;
}

.lb-btn-outline {
  background: transparent;
  color: var(--color-primary);
  border: 2px solid var(--color-primary);
}

.lb-btn-outline:hover {
  background: var(--color-primary);
  color: #FFFFFF;
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(232, 97, 58, 0.3);
  text-decoration: none;
}

.lb-btn-white {
  background: #FFFFFF;
  color: var(--color-primary);
  box-shadow: var(--shadow-card);
}

.lb-btn-white:hover {
  transform: translateY(-2px) scale(1.02);
  box-shadow: var(--shadow-hover);
  color: var(--color-primary-dark);
  text-decoration: none;
}

/* === 通用卡片样式 === */
.lb-card {
  background: var(--color-card);
  border-radius: var(--radius-lg);
  padding: var(--space-lg);
  box-shadow: var(--shadow-card);
  transition: var(--transition);
  border: 1px solid rgba(0, 0, 0, 0.03);
}

.lb-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-hover);
}

/* === 通用标签样式 === */
.lb-tag {
  display: inline-flex;
  align-items: center;
  padding: 4px 12px;
  font-size: var(--font-size-xs);
  font-weight: 500;
  border-radius: var(--radius-full);
  background: var(--color-primary-light);
  color: var(--color-primary);
}

.lb-tag-secondary {
  background: var(--color-secondary-light);
  color: #B87A00;
}

/* === 链接样式 === */
a {
  color: var(--color-primary);
  text-decoration: none;
  transition: var(--transition-fast);
}

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

/* === 分割线 === */
.lb-divider {
  height: 1px;
  background: linear-gradient(to right, transparent, rgba(0,0,0,0.06), transparent);
  margin: var(--space-xl) 0;
}

/* === 容器 === */
.lb-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--space-lg);
}

/* === 节标题 === */
.lb-section-title {
  font-size: var(--font-size-h2);
  font-weight: 700;
  color: var(--color-text);
  text-align: center;
  margin-bottom: var(--space-xs);
}

.lb-section-subtitle {
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
  text-align: center;
  margin-bottom: var(--space-2xl);
}

/* === 滚动动画基础类 - JS启用后才动画，默认内容可见 === */
.lb-fade-in {
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.lb-animate .lb-fade-in {
  opacity: 0;
  transform: translateY(20px);
}

.lb-animate .lb-fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* === Utility Classes === */
.text-primary { color: var(--color-primary) !important; }
.text-secondary { color: var(--color-text-secondary) !important; }
.bg-warm { background-color: var(--color-bg-warm) !important; }
.bg-primary-light { background-color: var(--color-primary-light) !important; }

/* ==========================================
   全局交互动效增强
   ========================================== */
.site-header.scrolled, header.scrolled { box-shadow: 0 2px 20px rgba(0,0,0,0.08) !important; transition: box-shadow 0.3s ease; }
button:hover, input[type="submit"]:hover { transform: translateY(-2px) scale(1.02); transition: var(--transition); }
#back-to-top, .back-to-top { background: var(--gradient-primary) !important; color: #fff !important; border: none !important; border-radius: 50% !important; width: 48px !important; height: 48px !important; display: flex !important; align-items: center !important; justify-content: center !important; box-shadow: 0 4px 16px rgba(232,97,58,0.3) !important; }
#back-to-top:hover, .back-to-top:hover { transform: translateY(-4px) scale(1.1) !important; box-shadow: 0 8px 24px rgba(232,97,58,0.4) !important; }
.main-navigation a:hover, .primary-menu a:hover { color: var(--color-primary) !important; }
.nav-links .page-numbers.current { background: var(--color-primary) !important; color: #fff !important; }
.lb-mobile-nav { display: none; position: fixed; bottom: 0; left: 0; right: 0; background: #fff; box-shadow: 0 -2px 16px rgba(0,0,0,0.08); z-index: 1000; padding: 8px 0 env(safe-area-inset-bottom, 8px); }
.lb-mobile-nav-inner { display: flex; justify-content: space-around; align-items: center; }
.lb-mobile-nav-item { display: flex; flex-direction: column; align-items: center; text-decoration: none !important; color: var(--color-text-secondary) !important; font-size: 11px; padding: 4px 12px; }
.lb-mobile-nav-item.active, .lb-mobile-nav-item:hover { color: var(--color-primary) !important; }
.lb-mobile-nav-icon { font-size: 22px; margin-bottom: 2px; }
@media (max-width: 768px) { body { font-size: 17px !important; line-height: 1.75 !important; padding-bottom: 70px !important; } .lb-mobile-nav { display: flex !important; } .lb-container { padding: 0 16px !important; } .lb-trust-stats { grid-template-columns: repeat(2, 1fr) !important; } }