/**
 * ====================================================
 * COMMON.CSS - 码农链网站通用样式表
 * 适用于所有页面的基础样式和共享组件
 * 
 * 目录结构：
 * 1. CSS变量定义
 * 2. 基础样式重置
 * 3. 字体和排版系统
 * 4. 通用组件样式
 * 5. 导航栏样式
 * 6. 页脚样式
 * 7. 模态框样式
 * 8. 动画效果
 * 9. 响应式设计
 * 10. 工具类
 * ====================================================
 */

/* ====================================================
   1. CSS变量定义 - 全局设计令牌
   ==================================================== */
   :root {
    /* 1.1 核心颜色系统 */
    --primary-color: #317bf6;
    --primary-hover: #3366ff;
    --secondary-color: #6200e3;
    --text-color: #ffffff;
    --text-color-dark: #2d2d2d;
    --text-color-light: rgba(255, 255, 255, 0.9);
    --text-color-muted: rgba(255, 255, 255, 0.7);
    --text-dark: #2c3e50;
    --text-muted: #6c757d;
    --border-color: rgba(255, 255, 255, 0.1);
    --border-light: rgba(44, 62, 80, 0.1);
    --overlay-color: rgba(0, 0, 0, 0.5);
    --overlay-bg: rgba(0, 0, 0, 0.3);
    --bg-light-hover: rgba(49, 123, 246, 0.1);
    --link-hover: var(--primary-hover);
    
    /* 1.2 字体系统 */
    --font-main: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif, var(--font-chinese);
    --font-chinese: 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', '微软雅黑', 'WenQuanYi Micro Hei', sans-serif;
    --font-monospace: SFMono-Regular, Menlo, Monaco, Consolas, 'Liberation Mono', 'Courier New', monospace;
    --font-paragraph: -apple-system, BlinkMacSystemFont, 'Segoe UI Variable Display', 'Segoe UI', Helvetica, 'Apple Color Emoji', Arial, sans-serif, 'Segoe UI Emoji', 'Segoe UI Symbol', var(--font-chinese);
    
    /* 1.3 字体大小系统 */
    --font-size-base: 16px;
    --font-size-sm: 0.875rem;    /* 14px */
    --font-size-md: 1rem;        /* 16px */
    --font-size-lg: 1.25rem;     /* 20px */
    --font-size-xl: 1.5rem;      /* 24px */
    --font-size-xxl: 2rem;       /* 32px */
    --font-size-xxxl: 2.5rem;    /* 40px */
    --font-size-jumbo: 3rem;     /* 48px */
    
    /* 1.4 字重系统 */
    --font-weight-normal: 400;
    --font-weight-medium: 500;
    --font-weight-semibold: 600;
    --font-weight-bold: 700;
    
    /* 1.5 行高系统 */
    --line-height-tight: 1.2;
    --line-height-base: 1.5;
    --line-height-relaxed: 1.8;
    
    /* 1.6 尺寸系统 */
    --header-height: 550px;
    --section-padding: 60px;
    --card-border-radius: 15px;
    --button-border-radius: 6px;
    
    /* 1.7 阴影和效果 */
    --card-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
    --button-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    --heading-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
    
    /* 1.8 过渡和动画 */
    --transition-fast: 0.2s;
    --transition-normal: 0.3s;
    --transition-slow: 0.5s;
    --transition-standard: all 0.3s ease;
    --animation-duration-fast: 0.6s;
    --animation-duration-normal: 1s;
    
    /* 1.9 字体渲染优化 */
    --text-rendering: optimizeLegibility;
    --webkit-font-smoothing: antialiased;
    --moz-osx-font-smoothing: grayscale;
    
    /* 1.10 响应式断点 */
    --breakpoint-xs: 400px;
    --breakpoint-sm: 576px;
    --breakpoint-md: 768px;
    --breakpoint-lg: 992px;
    --breakpoint-xl: 1200px;
    --navbar-height: 80px; /* 大致的导航栏高度 */
  }
  
  /* ====================================================
     2. 基础样式重置
     ==================================================== */
  * {
      margin: 0;
      padding: 0;
      border: 0;
      background: none;
      box-sizing: border-box;
      font-family: inherit;
  }
  
  body {
      font-family: var(--font-main), var(--font-chinese);
      color: #fff;
      font-size: var(--font-size-base);
      line-height: var(--line-height-base);
      overflow-x: hidden;
      background-color: #f8f9fa;
      text-rendering: var(--text-rendering);
      -webkit-font-smoothing: var(--webkit-font-smoothing);
      -moz-osx-font-smoothing: var(--moz-osx-font-smoothing);
  }
  
  /* ====================================================
     3. 字体和排版系统
     ==================================================== */
  
  /* 3.1 字体继承规则 */
  h1, h2 {
      font-family: var(--font-chinese);
  }
  
  h3, h4, h5, p, a, button, span, div, li {
      font-family: var(--font-chinese);
  }
  
  /* 3.2 标题样式层级 */
  h1 {
      font-weight: var(--font-weight-bold);
      font-size: var(--font-size-jumbo);
      text-shadow: 0 0 1px #ffffff, 0 0 0.5px #ffffff;
      color: #fff;
      margin: 0;
      padding: 0;
  }
  
  h2 {
      font-size: var(--font-size-xxxl);
      text-align: center;
      letter-spacing: 1px;
      text-shadow: 1px 1px 2px rgba(77, 75, 75, 0.3);
      color: #fff;
      margin-top: 1%;
  }
  
  h3 {
      font-size: var(--font-size-xl);

      font-weight: normal;
      line-height: 1.5;
  }
  
  h4, h5 {
      font-weight: var(--font-weight-semibold);
      font-size: var(--font-size-lg);
      line-height: 1.4;
      color: #fff;
  }
  
  /* 3.3 段落和文本样式 */
  p {
      font-size: var(--font-size-md);
      color: rgba(255, 255, 255, 0.8);
      font-weight: var(--font-weight-normal);
      line-height: var(--line-height-base);
  }
  
  /* 3.4 链接样式 */
  a {
      padding: 2px;
      display: inline-block;
      transition: var(--transition-standard);
  }
  
  /* 3.5 列表样式 */
  li {
      color: #6c757d;
  }
  
  ul li, ul li a {
      color: #6c757d;
      transition: all 0.3s ease;
  }
  
  ul li a:hover {
      color: #c62828;
      text-decoration: none;
  }
  
  /* ====================================================
     4. 通用组件样式
     ==================================================== */
  
  /* 4.1 标题和区块标题 */
  .title_header, .title, .section-header, .act_2 {
      position: relative;
      z-index: 2;
      padding: 1rem 0;
  }
  
  .title_header h1, .title h1, .section-header h2, .act_2 h2 {
      font-size: var(--font-size-xxxl);
      font-weight: var(--font-weight-bold);
      text-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
      color: #ffffff;
      animation: fadeInUp 1s ease;
      position: relative;
  }
  
  .title_header h3, .title h3, .section-header h3 {
      font-weight: var(--font-weight-normal);
      opacity: 0.9;
      color: #c5c1c1;
      max-width: 800px;
      animation: fadeInUp 1s ease 0.2s backwards;
      text-shadow: 0 1px 2px rgba(0, 0, 0, 0.1);
  }
  
  .title_header h1::after, .title h1::after, .section-header h2::after, .act_2 h2::after {
      content: '';
      position: absolute;
      left: 50%;
      transform: translateX(-50%);
      bottom: -10px;
      width: 80px;
      height: 3px;
      background: linear-gradient(90deg, var(--primary-color), rgba(49, 123, 246, 0.4));
      border-radius: 2px;
  }
  
  /* 4.2 卡片组件 */
  .bg-glass {
      background: rgba(0, 0, 0, 0.5);
      backdrop-filter: blur(10px);
      border: 1px solid rgba(255, 255, 255, 0.1);
      border-radius: 15px;
  }
  
  .card-base, .hover-card, .bg-glass {
      border-radius: var(--card-border-radius);
      background: rgba(255, 255, 255, 0.05);
      backdrop-filter: blur(10px);
      border: 1px solid var(--border-color);
      transition: all var(--transition-normal) ease;
      position: relative;
      overflow: hidden;
  }
  
  .card-base:hover, .hover-card:hover, .bg-glass:hover {
      transform: translateY(-8px);
      box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
      z-index: 2;
  }
  
  .card-title {
      font-weight: var(--font-weight-semibold);
      font-size: var(--font-size-lg);
      color: var(--text-color);
      margin-bottom: 1rem;
  }
  
  .card-text {
      font-size: var(--font-size-md);
      color: var(--text-color-light);
      line-height: var(--line-height-base);
  }
  
  /* 4.3 图标组件 */
  .icon-wrapper {
      width: 80px;
      height: 80px;
      margin: 0 auto;
      display: flex;
      align-items: center;
      justify-content: center;
      position: relative;
  }
  
  .icon-wrapper img {
      transition: transform 0.5s ease;
  }
  
  .icon-wrapper::after {
      content: '';
      position: absolute;
      width: 100%;
      height: 100%;
      background: radial-gradient(circle, rgba(49, 123, 246, 0.2), transparent 70%);
      border-radius: 50%;
      z-index: -1;
      animation: pulse 2s infinite;
  }
  
  .card:hover .icon-wrapper img {
      transform: scale(1.1) rotate(5deg);
  }
  
  .icon-base {
      width: 70px;
      height: 70px;
      margin: 0 auto 1.5rem;
      display: flex;
      align-items: center;
      justify-content: center;
      background: rgba(49, 123, 246, 0.1);
      border-radius: 50%;
      transition: all 0.3s ease;
      position: relative;
  }
  
  .icon-base i, .icon-base svg {
      font-size: var(--font-size-xl);
      color: var(--primary-color);
      position: relative;
      z-index: 2;
  }
  
  .icon-base::before {
      content: '';
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background: radial-gradient(circle, rgba(49, 123, 246, 0.3), transparent 70%);
      animation: pulse 2s infinite;
      border-radius: 50%;
  }
  
  .icon-pulse::after {
      content: '';
      position: absolute;
      width: 100%;
      height: 100%;
      border-radius: 50%;
      border: 2px solid rgba(255, 255, 255, 0.1);
      box-sizing: border-box;
      animation: pulseRing 2s infinite;
  }
  
  .feature-icon {
      width: 60px;
      height: 60px;
      border-radius: 50%;
      background: rgba(49, 123, 246, 0.1);
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 1rem;
      position: relative;
      overflow: hidden;
  }
  
  .feature-icon i {
      font-size: 1.8rem;
      color: var(--primary-color);
      position: relative;
      z-index: 2;
  }
  
  .feature-icon::before {
      content: '';
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background: radial-gradient(circle, rgba(49, 123, 246, 0.3), transparent 70%);
      animation: pulse 2s infinite;
  }
  
  /* 4.4 按钮组件 */
  .btn-explore {
      display: inline-block;
      margin-top: 1.5rem;
      padding: 0.75rem 2rem;
      background: linear-gradient(90deg, var(--primary-color), #2a52cc);
      border: none;
      border-radius: 50px;
      color: white;
      font-weight: 600;
      text-decoration: none;
      text-align: center;
      box-shadow: 0 4px 15px rgba(49, 123, 246, 0.4);
      transition: all 0.3s ease;
      position: relative;
      overflow: hidden;
  }
  
  .btn-explore:hover {
      box-shadow: 0 8px 25px rgba(49, 123, 246, 0.6);
      transform: translateY(-3px);
  }
  
  .btn-explore::after {
      content: '';
      position: absolute;
      top: -50%;
      left: -50%;
      width: 200%;
      height: 200%;
      background: rgba(255, 255, 255, 0.1);
      transform: rotate(45deg);
      transition: all 0.3s ease;
      z-index: 1;
  }
  
  .btn-explore:hover::after {
      left: 100%;
  }
  
  .btn-explore span {
      position: relative;
      z-index: 2;
      color: white;
  }
  
  .btn-base {
      padding: 0.75rem 2rem;
      border-radius: 50px;
      font-weight: var(--font-weight-semibold);
      transition: all var(--transition-normal) ease;
      position: relative;
      overflow: hidden;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      box-shadow: var(--button-shadow);
      list-style: none;
      text-decoration: none;
  }
  
  .btn-primary {
      background: var(--primary-color);
      color: white;
  }
  
  .btn-base:hover {
      transform: translateY(-3px);
      box-shadow: 0 8px 20px rgba(0, 0, 0, 0.15);
  }
  
  /* 4.5 标题与按钮布局 */
  .section-header .title-button-row {
      display: flex;
      justify-content: space-between;
      align-items: center;
      margin-top: 1rem;
      margin-bottom: 1rem;
  }
  
  .section-header .title-button-row h3 {
      margin: 0;
      padding: 0;
  }
  
  .section-header .title-button-row .btn-explore {
      margin: 0;
  }
  
  /* 4.6 英雄区域组件 */
  .hero-section {
      position: relative;
      height: var(--header-height, 550px);
      overflow: hidden;
      background-size: cover;
      background-position: center;
      background-repeat: no-repeat;
      display: flex;
      align-items: center;
      justify-content: center;
  }
  
  .hero-section::before {
      content: '';
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background: linear-gradient(rgba(0, 0, 0, 0.2), rgba(0, 0, 0, 0.4));
      z-index: 1;
      opacity: 0.8;
  }
  
  .hero-content {
      position: relative;
      z-index: 2;
      width: 100%;
      max-width: 1200px;
      padding: 0 20px;
      display: flex;
      flex-direction: column;
      justify-content: center;
      align-items: center;
      height: 100%;
  }
  
  /* 合并选择器，让 .hero-content 和 .hero-content1 共享相同的 h1 和 h3 样式 */
  .hero-content h1,
  .hero-content1 h1 {
      font-size: var(--font-size-jumbo);
      font-weight: var(--font-weight-bold);
      margin-bottom: 1.5rem;
      max-width: 800px;
      color: var(--text-color);
     
      line-height: var(--line-height-tight);
      letter-spacing: 0.5px;
      animation: fadeInUp 1s ease;
    
      text-shadow: 0 2px 8px rgba(0, 0, 0, 0.3), 0 0 2px rgba(255, 255, 255, 0.5);
      background: linear-gradient(to bottom, #ffffff, rgba(255, 255, 255, 0.85));
      -webkit-background-clip: text;
      background-clip: text;
      -webkit-text-fill-color: transparent;
  }
  
  .hero-content h3,
  .hero-content1 h3 {
      font-size: var(--font-size-xl);
      font-weight: var(--font-weight-normal);
      margin-bottom: 2rem;
      max-width: 700px;
      color: var(--text-color-light);
      line-height: var(--line-height-base);
      animation: fadeInUp 1s ease 0.2s backwards;
      text-shadow: 0 1px 4px rgba(0, 0, 0, 0.2);
      opacity: 0.95;
      letter-spacing: 0.3px;
  }

  .hero-content1 {
    position: relative;
    z-index: 2;
    width: 100%;
    max-width: 1200px;
    padding: 0 20px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    height: 100%;
  }
  
  /* 4.7 视频背景 */
  .video-background {
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      z-index: 0;
      overflow: hidden;
  }
  
  .video-background video {
      min-width: 100%;
      min-height: 100%;
      width: auto;
      height: auto;
      position: absolute;
      top: 50%;
      left: 50%;
      transform: translate(-50%, -50%);
      object-fit: cover;
  }
  
  /* 4.8 按钮容器 */
  .btn-container,
  .hero-content .btn-container {
      flex-wrap: wrap;
      gap: 1rem;
      margin: 0;
      padding: 0;
      animation: fadeInUp 1s ease 0.4s backwards;
  }
  
  .btn-container .btn,
  .hero-content .btn-container .btn {
      margin: 0;
      position: relative;
      overflow: hidden;
      min-width: 160px;
  }
  
  .hero-btn::after {
      content: '';
      position: absolute;
      top: -50%;
      left: -50%;
      width: 200%;
      height: 200%;
      background: rgba(255, 255, 255, 0.1);
      transform: rotate(45deg);
      transition: all 0.3s ease;
      z-index: 1;
      opacity: 0;
  }
  
  .btn-container .btn:hover::after,
  .hero-content .btn-container .btn:hover::after {
      left: 100%;
      opacity: 1;
  }
  
  /* 4.9 特殊组件样式 */
  .biaoqian {
      margin-bottom: 40px;
      border-bottom: 2px solid #e0e0e0;
      padding-bottom: 15px;
      display: flex;
      justify-content: space-between;
      align-items: center;
  }
  
  .biaoqian h3 {
      color: #2d2d2d;
      font-weight: 600;
      margin: 0;
      position: relative;
      padding-bottom: 10px;
  }
  
  .biaoqian h3::after {
      content: '';
      position: absolute;
      left: 0;
      bottom: 0;
      width: 60px;
      height: 3px;
      background: linear-gradient(90deg, var(--primary-color), rgba(49, 123, 246, 0.4));
      border-radius: 2px;
  }
  
  .biaoqian a, .biaoqian h4 a {
      text-decoration: none;
      color: #0085ff;
      font-weight: 500;
      transition: all 0.3s ease;
      display: flex;
      align-items: center;
  }
  
  .biaoqian a:hover, .biaoqian h4 a:hover {
      color: var(--link-hover);
  }
  
  .biaoqian a i, .biaoqian h4 a i {
      margin-left: 5px;
  }
  
  /* 4.10 内容块样式 */
  .feature-box .content h5 {
      font-size: var(--font-size-md);
      font-weight: var(--font-weight-semibold);
      color: #fff;
      margin-bottom: 1rem;
  }
  
  .feature-box .content p {
      color: rgba(255, 255, 255, 0.7);
      font-size: var(--font-size-sm);
      line-height: var(--line-height-base);
  }
  
  .lab-content h4 {
      margin-bottom: 0.8rem;
      font-weight: var(--font-weight-semibold);
      color: #fff;
      font-size: var(--font-size-lg);
  }
  
  .lab-content p {
      margin: 0;
      color: rgba(255, 255, 255, 0.7);
      font-size: var(--font-size-md);
      line-height: var(--line-height-base);
  }
  
  .community-card h4 {
      margin: 0;
      font-size: var(--font-size-lg);
      font-weight: var(--font-weight-semibold);
      text-align: center;
      color: #fff;
  }
  
  .community-card p {
      color: rgba(255, 255, 255, 0.7);
      margin-bottom: 1rem;
      font-size: var(--font-size-md);
      line-height: var(--line-height-base);
  }
  
  /* 4.11 图标容器变体 */
  .icon-container {
      display: flex;
      align-items: center;
      justify-content: center;
      position: relative;
      border-radius: 50%;
      transition: all var(--transition-normal) ease;
  }
  
  .icon-sm { width: 40px; height: 40px; }
  .icon-md { width: 60px; height: 60px; }
  .icon-lg { width: 80px; height: 80px; }
  
  .icon-primary {
      background: var(--bg-light-hover);
      color: var(--primary-color);
  }
  
  .icon-pulse::before {
      content: '';
      position: absolute;
      width: 100%;
      height: 100%;
      border-radius: 50%;
      background: radial-gradient(circle, rgba(49, 123, 246, 0.3), transparent 70%);
      animation: pulse 2s infinite;
  }
  
  /* ====================================================
     5. 导航栏样式
     ==================================================== */
  #nav {
      background: url(../img/aheader.webp) no-repeat center;
      background-size: cover;
 
      top: 0;
    
  }
  
  .navigation {
      text-align: center;
      background: #ffffff;
      opacity: 0.97;
      position: relative;
      padding: 15px 0;
      width: 100%;
  }
 
  
  .navbar {
      background: transparent !important;
      padding: 0;
      margin-bottom: 0;
  }
  
  .navbar-brand {
      padding: 0;
  }
  
  .navbar-brand img {
      height: 45px;
      transition: transform 0.3s ease;
  }
  
  .navbar-brand img:hover {
      transform: scale(1.1);
  }
  
  .navbar-nav .nav-item {
      align-items: center;
      margin: 0 5px;
  }
  
  .navbar-nav .nav-link {
      color: #2c3e50 !important;
      font-size: 1.1em;
      line-height: 1.5;
      padding: 8px 15px;
      transition: all 0.3s ease;
      font-weight: 600;
  }
  
  .nav-link:hover,
  .nav-link:focus,
  .nav-link.active {
      color: var(--primary-hover) !important;
      font-weight: bold;
      background-color: transparent;
  }
  
  .navbar-toggler {
      border-color: rgba(44, 62, 80, 0.5);
      margin-right: 15px;
  }
  
  .navbar-toggler-icon {
      background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 30 30'%3e%3cpath stroke='rgba(44, 62, 80, 0.85)' stroke-linecap='round' stroke-miterlimit='10' stroke-width='2' d='M4 7h22M4 15h22M4 23h22'/%3e%3c/svg%3e") !important;
  }
  
  /* ====================================================
     6. 页脚样式
     ==================================================== */
  footer {
      position: relative;
      /* border: 3px solid red; */
  }
  
  footer h5{
      transition: all 0.3s ease;
      margin-top: 0px;
      /* border: 1px solid red; */
  }
  
  footer h5:hover {
      color: var(--link-hover);
  }
  
  footer ul li a {
      transition: all 0.3s ease;
      font-size: 15px;
  }
  
  footer ul li a:hover {
      color: var(--link-hover);
      transform: translateX(3px);
      display: inline-block;
  }
  
  footer .social-icon {
      height: 40px;
      width: 40px;
      background: rgba(44, 62, 80, 0.05);
      border: 1px solid rgba(44, 62, 80, 0.1);
      transition: all 0.3s ease;
  }
  
  footer .social-icon:hover {
      background: rgba(49, 123, 246, 0.1);
      transform: translateY(-3px);
  }
  
  footer .social-icon:hover i,
  footer .social-icon:hover svg {
      color: #317bf6;
  }
  
  footer p a:hover {
      color: #317bf6;
      text-decoration: underline;
  }
  
  footer ul li {
      color: #6c757d;
  }
  
  .dropdown-menu {
      background-color: #ffffff;
  }
  
  .dropdown-item {
      color: #2c3e50;
  }
  
  .dropdown-item:hover, 
  .dropdown-item:focus {
      background-color: rgba(49, 123, 246, 0.05);
      color: #317bf6;
  }
  
  .hover-text-white {
      color: #6c757d !important;
      transition: all 0.3s ease;
  }
  
  .hover-text-white:hover {
      color: var(--link-hover) !important;
  }
  
  .social-icons-container .social-icon {
      height: 40px;
      width: 40px;
      display: flex;
      align-items: center;
      justify-content: center;
      border-radius: 50%;
      background: rgba(44, 62, 80, 0.05);
      border: 1px solid rgba(44, 62, 80, 0.1);
      transition: all 0.3s ease;
  }
  
  .social-icons-container .social-icon:hover {
      background: rgba(49, 123, 246, 0.1);
      transform: translateY(-3px);
  }
  
  .social-icons-container .social-icon .icon {
      transition: all 0.3s ease;
  }
  
  .social-icons-container .social-icon:hover .icon {
      transform: scale(1.1);
  }
  
  /* ====================================================
     7. 模态框样式
     ==================================================== */
  
  /* 7.1 微信二维码弹窗 */
  #wechatModal .modal-content {
      background-color: #ffffff;
      border-radius: 12px;
      border: none;
      box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
  }
  
  #wechatModal .modal-header {
      border-bottom: 1px solid rgba(44, 62, 80, 0.1);
      padding: 1rem 1.5rem;
  }
  
  #wechatModal .modal-title {
      font-weight: 600;
      color: #2c3e50;
  }
  
  #wechatModal .modal-body {
      padding: 2rem;
  }
  
  #wechatModal img {
      border-radius: 8px;
      box-shadow: 0 4px 15px rgba(0, 0, 0, 0.05);
  }
  
  #wechatModal .btn-close {
      opacity: 0.5;
      transition: all 0.3s ease;
  }
  
  #wechatModal .btn-close:hover {
      opacity: 1;
  }
  
  .wechat-icon:hover {
      background-color: rgba(49, 123, 246, 0.1) !important;
      transform: translateY(-3px);
  }
  
  /* 7.2 法律信息弹窗 */
  #serviceAgreementModal .modal-content,
  #privacyPolicyModal .modal-content,
  #copyrightModal .modal-content {
      background-color: #ffffff;
      border-radius: 12px;
      border: none;
      box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
  }
  
  #serviceAgreementModal .modal-header,
  #privacyPolicyModal .modal-header,
  #copyrightModal .modal-header {
      border-bottom: 1px solid rgba(44, 62, 80, 0.1);
      padding: 1rem 1.5rem;
  }
  
  #serviceAgreementModal .modal-title,
  #privacyPolicyModal .modal-title,
  #copyrightModal .modal-title {
      font-weight: 600;
      color: #2c3e50;
  }
  
  #serviceAgreementModal .modal-body,
  #privacyPolicyModal .modal-body,
  #copyrightModal .modal-body {
      padding: 1.5rem;
      color: #6c757d;
      max-height: 70vh;
      overflow-y: auto;
  }
  
  #serviceAgreementModal .modal-body h6,
  #privacyPolicyModal .modal-body h6,
  #copyrightModal .modal-body h6 {
      color: #2c3e50;
      margin-top: 1.5rem;
      margin-bottom: 0.75rem;
  }
  
  #serviceAgreementModal .modal-body p,
  #privacyPolicyModal .modal-body p,
  #copyrightModal .modal-body p {
      margin-bottom: 0.75rem;
      line-height: 1.6;
      color: #6c757d;
  }
  
  #serviceAgreementModal .modal-body ul,
  #privacyPolicyModal .modal-body ul,
  #copyrightModal .modal-body ul {
      margin-bottom: 1rem;
      padding-left: 1.5rem;
  }
  
  #serviceAgreementModal .modal-body li,
  #privacyPolicyModal .modal-body li,
  #copyrightModal .modal-body li {
      margin-bottom: 0.5rem;
      color: #6c757d;
  }
  
  #serviceAgreementModal .modal-footer,
  #privacyPolicyModal .modal-footer,
  #copyrightModal .modal-footer {
      border-top: 1px solid rgba(44, 62, 80, 0.1);
      padding: 1rem;
  }
  
  #serviceAgreementModal .btn-secondary,
  #privacyPolicyModal .btn-secondary,
  #copyrightModal .btn-secondary {
      background-color: #6c757d;
      border: none;
      padding: 0.5rem 1.5rem;
      border-radius: 30px;
      font-weight: 500;
      transition: all 0.3s ease;
  }
  
  #serviceAgreementModal .btn-secondary:hover,
  #privacyPolicyModal .btn-secondary:hover,
  #copyrightModal .btn-secondary:hover {
      background-color: #5a6268;
      transform: translateY(-2px);
  }
  
  /* ====================================================
     8. 动画效果
     ==================================================== */
  
  /* 8.1 关键帧动画定义 */
  @keyframes fadeInUp {
      from {
          opacity: 0;
          transform: translateY(20px);
      }
      to {
          opacity: 1;
          transform: translateY(0);
      }
  }
  
  @keyframes fadeInDown {
      from {
          opacity: 0;
          transform: translateY(-20px);
      }
      to {
          opacity: 1;
          transform: translateY(0);
      }
  }
  
  @keyframes fadeInLeft {
      from {
          opacity: 0;
          transform: translateX(-20px);
      }
      to {
          opacity: 1;
          transform: translateX(0);
      }
  }
  
  @keyframes fadeInRight {
      from {
          opacity: 0;
          transform: translateX(20px);
      }
      to {
          opacity: 1;
          transform: translateX(0);
      }
  }
  
  @keyframes shimmer {
      0% {
          transform: translateX(-100%);
      }
      100% {
          transform: translateX(100%);
      }
  }
  
  @keyframes pulse {
      0% {
          transform: scale(1);
          opacity: 0.5;
      }
      50% {
          transform: scale(1.2);
          opacity: 0.2;
      }
      100% {
          transform: scale(1);
          opacity: 0.5;
      }
  }
  
  @keyframes pulseIcon {
      0% {
          transform: scale(1);
          opacity: 0.5;
      }
      50% {
          transform: scale(1.2);
          opacity: 0.2;
      }
      100% {
          transform: scale(1);
          opacity: 0.5;
      }
  }
  
  @keyframes rotate {
      0% {
          transform: rotate(0deg);
      }
      100% {
          transform: rotate(360deg);
      }
  }
  
  @keyframes pulseLight {
      0% {
          opacity: 0.3;
      }
      50% {
          opacity: 0.7;
      }
      100% {
          opacity: 0.3;
      }
  }
  
  @keyframes gradientShift {
      0% {
          background-position: 0% 0%, 0 0, 0 0;
      }
      100% {
          background-position: 100% 100%, 50px 0, 0 50px;
      }
  }
  
  @keyframes pulseRing {
      0% {
          transform: scale(0.8);
          opacity: 0.8;
      }
      50% {
          transform: scale(1.2);
          opacity: 0.3;
      }
      100% {
          transform: scale(0.8);
          opacity: 0.8;
      }
  }
  
  /* 8.2 动画类 */
  .fade-in-up {
      opacity: 0;
      transform: translateY(20px);
      animation: fadeInUp 0.6s ease forwards;
  }
  
  .fade-in-down {
      opacity: 0;
      transform: translateY(-20px);
      animation: fadeInDown 0.6s ease forwards;
  }
  
  .fade-in-left {
      opacity: 0;
      transform: translateX(-20px);
      animation: fadeInLeft 0.6s ease forwards;
  }
  
  .fade-in-right {
      opacity: 0;
      transform: translateX(20px);
      animation: fadeInRight 0.6s ease forwards;
  }
  
  .animate {
      animation-duration: var(--animation-duration-normal);
      animation-fill-mode: forwards;
      animation-timing-function: ease;
  }
  
  .animate-up { animation-name: fadeInUp; }
  .animate-down { animation-name: fadeInDown; }
  .animate-left { animation-name: fadeInLeft; }
  .animate-right { animation-name: fadeInRight; }
 
  
  /* 9.2 打印样式 */
  @media print {
      a[href]:after {
          content: " (" attr(href) ")";
      }
      
      .no-print, .no-print * {
          display: none !important;
      }
  }
  
  /* ====================================================
     10. 工具类
     ==================================================== */
  
  /* 10.1 文本颜色 */
  .text-primary {
      color: var(--primary-color) !important;
  }
  
  .text-white-50 {
      color: rgba(133, 21, 21, 0.7) !important;
  }
  
  .text-right {
      text-align: right;
      margin-top: 0%;
      margin-bottom: 0%;
  }
  
  /* 10.2 特性列表 */
  .feature-list li {
      color: #6c757d;
  }
  
  .feature-list li i {
      color: inherit;
  }
  
  li a {
      color: #6c757d;
      transition: all 0.3s ease;
  }
  
  li a:hover {
      color: #c62828;
  }
  
  /* 10.3 通用过渡 */
  a, button, .btn, .nav-link, .card, .hover-card, .icon-container {
      transition: var(--transition-standard);
  }
  
  /* 10.4 应用方式示例 */
  .section-header h2 {
      font-size: var(--font-size-xxxl);
      font-weight: var(--font-weight-bold);
      text-shadow: var(--heading-shadow);
      position: relative;
  }
  
  /* 新增：导航栏登录注册按钮样式 */
  #user-state-container .btn {
      font-size: 0.9rem;
      font-weight: 500;
      border-radius: 20px;
      padding: 8px 20px;
      transition: all 0.3s ease;
      border: none;
      text-decoration: none;

  }
  
  #user-state-container .btn-primary {
      background: linear-gradient(45deg, var(--primary-color), #4d7fff);
      color: white;
      box-shadow: 0 2px 8px rgba(49, 123, 246, 0.3);
  }
  
  #user-state-container .btn-primary:hover {
      background: linear-gradient(45deg, #0b5ed7, var(--primary-color));
      transform: translateY(-1px);
      box-shadow: 0 4px 12px rgba(49, 123, 246, 0.4);
      color: white;
      text-decoration: none;
  }
  
  /* 用户下拉菜单样式优化 */
  #user-state-container .dropdown-toggle {
      border: none;
      background: transparent;
      color: var(--text-color);
      text-decoration: none;
  }
  
  #user-state-container .dropdown-toggle:hover {
      color: var(--primary-color);
      text-decoration: none;
  }
  
  #user-state-container .dropdown-toggle::after {
      margin-left: 0.5rem;
  }
  
  /* 用户头像样式 */
  #user-state-container .user-icon {
      border: 2px solid var(--primary-color);
      transition: all 0.3s ease;
  }
  
  #user-state-container .user-icon:hover {
      transform: scale(1.05);
      border-color: #4d7fff;
  }