/* 性能优化基础样式 */
    :root {
      --primary: #3B82F6;
      --primary-light: #EFF6FF;
      --secondary: #64748B;
      --dark: #1E293B;
      --light: #F8FAFC;
    }
    
    body {
      font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
      color: var(--dark);
      line-height: 1.6;
    }
    
    /* 导航栏优化 */
    .navbar {
      background-color: transparent;
      padding: 20px 0;
      position: sticky;
      top: 0;
      width: 100%;
      z-index: 1000;
    }
    
    .navbar-brand img {
      height: auto;
      width: auto;
      max-height: 50px;
    }
    
    .navbar-brand {
      margin-right: 40px;
      color: #3B82F6 !important;
    }
    
    .nav-link {
      color: #2563EB !important;
      font-weight: 700;
      padding: 8px 20px;
      font-size: 16px;
      margin-right: 10px;
    }
    
    .nav-link:hover {
      color: #1D4ED8 !important;
      opacity: 0.8;
    }
    
    .nav-link.active {
      color: #2563EB !important;
      font-weight: 700;
    }
    
    .btn-login {
      background-color: var(--primary);
      color: white !important;
      border-radius: 4px;
      padding: 10px 24px;
      font-weight: 500;
      font-size: 16px;
      text-decoration: none;
    }

    .btn-login:hover {
      background-color: #1D4ED8 !important;
      color: white !important;
    }

    .navbar-collapse {
      background: rgba(102, 126, 234, 0.1) !important;
      border-radius: 8px;
      margin-top: 10px;
      padding: 15px;
    }
    
    /* 关于我们页面特定样式 */
    .about-hero {
      background-color: #f5f8ff;
      padding: 120px 0 60px;
      position: relative;
    }
    
    .about-hero h1 {
      font-size: 42px;
      font-weight: 700;
      color: #2563EB;
      margin-bottom: 20px;
    }
    
    .about-hero p {
      font-size: 18px;
      color: #64748B;
      max-width: 800px;
      margin: 0 auto;
    }
    
    .about-section {
      padding: 80px 0;
    }
    
    .about-section h2 {
      font-size: 32px;
      font-weight: 700;
      color: var(--dark);
      margin-bottom: 30px;
    }
    
    .about-section h3 {
      font-size: 24px;
      font-weight: 600;
      color: var(--primary);
      margin-bottom: 20px;
      margin-top: 40px;
    }
    
    .about-section p {
      font-size: 16px;
      line-height: 1.8;
      color: var(--secondary);
      margin-bottom: 20px;
    }
    
    .about-section ul {
      margin-bottom: 30px;
    }
    
    .about-section li {
      margin-bottom: 10px;
      line-height: 1.7;
    }
    
    .about-card {
      background-color: white;
      border-radius: 12px;
      padding: 30px;
      box-shadow: 0 5px 15px rgba(0,0,0,0.05);
      height: 100%;
      transition: all 0.3s ease;
    }
    
    .about-card:hover {
      transform: translateY(-5px) translateZ(0);
      box-shadow: 0 10px 25px rgba(0,0,0,0.1);
    }
    
    /* 性能优化样式 */
    .about-card {
      transform: translateZ(0);
      backface-visibility: hidden;
      contain: layout style;
    }
    
    .about-icon {
      transform: translateZ(0);
      backface-visibility: hidden;
    }
    
    .about-card h4 {
      font-size: 20px;
      font-weight: 600;
      color: var(--dark);
      margin-bottom: 15px;
    }
    
    .about-card p {
      font-size: 15px;
      color: var(--secondary);
    }

    .login-modal-image {
      max-height: 200px;
    }
    
    .about-icon {
      width: 60px;
      height: 60px;
      border-radius: 50%;
      background-color: var(--primary-light);
      color: var(--primary);
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 20px;
      font-size: 28px;
    }
    
    .team-section {
      background-color: #f8fafc;
      padding: 80px 0;
    }
    
    .timeline {
      position: relative;
      padding-left: 30px;
      margin-top: 40px;
    }
    
    .timeline::before {
      content: '';
      position: absolute;
      left: 0;
      top: 0;
      bottom: 0;
      width: 2px;
      background-color: var(--primary);
    }
    
    .timeline-item {
      position: relative;
      padding-bottom: 30px;
    }
    
    .timeline-item::before {
      content: '';
      position: absolute;
      left: -34px;
      top: 0;
      width: 10px;
      height: 10px;
      border-radius: 50%;
      background-color: var(--primary);
    }
    
    .timeline-year {
      font-weight: 700;
      color: var(--primary);
      margin-bottom: 10px;
    }
    
    /* 修改移动端菜单按钮为蓝色横线 - 修复颜色值 */
    .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%2837, 99, 235, 1%29' stroke-linecap='round' stroke-miterlimit='10' stroke-width='2' d='M4 7h22M4 15h22M4 23h22'/%3e%3c/svg%3e") !important;
      display: inline-block;
      width: 1.5em;
      height: 1.5em;
      vertical-align: middle;
    }
    
    /* 确保移动端菜单按钮正确显示 */
    .navbar-toggler {
      border-color: #3B82F6 !important;
    }
    
    .navbar-toggler:focus {
      box-shadow: 0 0 0 0.2rem rgba(59, 130, 246, 0.25) !important;
    }
    
    /* 确保移动端菜单栏样式正确 */
    @media (max-width: 991.98px) {
      .navbar-collapse {
        background-color: white !important;
        padding: 1rem;
        border-radius: 0.5rem;
        margin-top: 0.5rem;
        box-shadow: 0 4px 12px rgba(0,0,0,0.1);
      }
      
      .nav-link {
        padding: 12px 20px;
        border-bottom: 1px solid rgba(0,0,0,0.05);
        font-weight: 700 !important;
      }
      
      .nav-link:last-child {
        border-bottom: none;
      }
      
      .navbar {
        background-color: white;
        padding: 10px 0;
        position: sticky;
        top: 0;
        box-shadow: 0 2px 10px rgba(0,0,0,0.1);
        z-index: 1000;
      }
      
      .navbar-brand {
        margin-right: 0;
      }
      
      .navbar-brand img {
        max-height: 40px;
      }
      
      .navbar-toggler {
        border: none;
        padding: 0.25rem 0.5rem;
        margin-left: auto;
      }
      
      .navbar-toggler:focus {
        box-shadow: none;
        outline: none;
      }
      
      .about-hero {
        padding-top: 80px;
      }
      
      .about-hero h1 {
        font-size: 28px !important;
      }
      
      .about-section h2 {
        font-size: 24px !important;
      }
      
      .about-card {
        margin-bottom: 1rem;
      }
      
      .btn-login {
        margin-top: 1rem;
        display: block;
        text-align: center;
      }
    }