/* roulang page: index */
/* 设计变量与全局重置 */
    :root {
      --red: #D42027;
      --red-hover: #B01A1F;
      --dark: #1A1A1A;
      --gray-text: #333333;
      --gray-light: #666666;
      --white: #FFFFFF;
      --off-white: #F7F7F7;
      --bg-light: #FAFAFA;
      --border-light: #E0E0E0;
      --green: #00C853;
      --shadow-sm: 0 4px 20px rgba(0,0,0,0.04);
      --shadow-md: 0 12px 32px rgba(0,0,0,0.08);
      --radius-md: 12px;
      --radius-lg: 16px;
      --radius-btn: 8px;
      --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans SC", sans-serif;
      --max-width: 1200px;
      --nav-height: 72px;
      --section-padding: 100px;
    }
    
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }
    
    html {
      scroll-behavior: smooth;
    }
    
    body {
      font-family: var(--font-sans);
      color: var(--gray-text);
      background-color: var(--white);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }
    
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    
    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s ease;
    }
    
    .container {
      max-width: var(--max-width);
      margin-left: auto;
      margin-right: auto;
      padding-left: 24px;
      padding-right: 24px;
    }
    
    /* 板块通用间距 */
    .section {
      padding-top: var(--section-padding);
      padding-bottom: var(--section-padding);
    }
    
    /* 标题装饰线 */
    .section-title {
      font-size: 36px;
      font-weight: 700;
      color: var(--dark);
      text-align: center;
      margin-bottom: 16px;
      position: relative;
      display: inline-block;
      left: 50%;
      transform: translateX(-50%);
    }
    .section-title::after {
      content: '';
      position: absolute;
      bottom: -8px;
      left: 50%;
      transform: translateX(-50%);
      width: 60px;
      height: 4px;
      background-color: var(--red);
      border-radius: 2px;
    }
    
    .section-subtitle {
      text-align: center;
      color: var(--gray-light);
      font-size: 18px;
      margin-bottom: 60px;
      margin-top: 16px;
    }
    
    /* 导航栏 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--nav-height);
      background: rgba(255,255,255,0.96);
      backdrop-filter: blur(8px);
      box-shadow: 0 1px 8px rgba(0,0,0,0.04);
      z-index: 50;
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 0 32px;
    }
    .logo {
      font-size: 24px;
      font-weight: 700;
      color: var(--red);
      letter-spacing: -0.5px;
    }
    .nav-links {
      display: flex;
      gap: 32px;
      align-items: center;
    }
    .nav-links a {
      font-weight: 500;
      font-size: 16px;
      color: var(--dark);
      transition: color 0.2s;
    }
    .nav-links a:hover {
      color: var(--red);
    }
    
    /* 移动端导航：底部胶囊 */
    .mobile-nav {
      display: none;
      position: fixed;
      bottom: 12px;
      left: 50%;
      transform: translateX(-50%);
      background: rgba(255,255,255,0.9);
      backdrop-filter: blur(20px);
      border-radius: 40px;
      padding: 8px 24px;
      box-shadow: 0 8px 30px rgba(0,0,0,0.08);
      z-index: 60;
      gap: 24px;
    }
    .mobile-nav a {
      display: flex;
      flex-direction: column;
      align-items: center;
      font-size: 12px;
      color: var(--gray-text);
      font-weight: 500;
    }
    .mobile-nav a i {
      font-size: 18px;
      margin-bottom: 2px;
    }
    .mobile-nav a:hover, .mobile-nav a.active {
      color: var(--red);
    }
    
    /* 按钮 */
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      font-weight: 600;
      border-radius: var(--radius-btn);
      transition: all 0.25s ease;
      cursor: pointer;
      border: none;
      padding: 14px 32px;
      font-size: 16px;
    }
    .btn-primary {
      background: var(--red);
      color: white;
    }
    .btn-primary:hover {
      background: var(--red-hover);
      transform: translateY(-2px);
      box-shadow: 0 8px 20px rgba(212,32,39,0.3);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--red);
      color: var(--red);
    }
    .btn-outline:hover {
      background: var(--red);
      color: white;
      transform: translateY(-2px);
    }
    
    /* 卡片系统 */
    .card {
      background: white;
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-sm);
      padding: 32px;
      transition: transform 0.3s ease, box-shadow 0.3s ease;
      height: 100%;
      display: flex;
      flex-direction: column;
    }
    .card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-md);
    }
    .icon-wrap {
      width: 48px;
      height: 48px;
      display: flex;
      align-items: center;
      justify-content: center;
      background: rgba(212,32,39,0.08);
      border-radius: 12px;
      margin-bottom: 20px;
      color: var(--red);
      font-size: 24px;
      transition: transform 0.2s;
    }
    .card:hover .icon-wrap {
      transform: rotate(5deg);
    }
    
    /* 价格卡片高亮 */
    .pricing-highlight {
      border: 2px solid var(--red);
      position: relative;
    }
    .badge {
      background: var(--green);
      color: white;
      font-size: 12px;
      font-weight: 600;
      padding: 4px 12px;
      border-radius: 20px;
      position: absolute;
      top: -12px;
      right: 24px;
    }
    
    /* 手风琴 */
    .faq-item {
      border-bottom: 1px solid var(--border-light);
    }
    .faq-question {
      width: 100%;
      background: transparent;
      border: none;
      padding: 20px 0;
      font-weight: 600;
      font-size: 18px;
      color: var(--dark);
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      text-align: left;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease, padding 0.4s ease;
      color: var(--gray-light);
      padding: 0 0;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-bottom: 20px;
    }
    .faq-icon {
      font-size: 20px;
      transition: transform 0.3s;
    }
    .faq-item.active .faq-icon {
      transform: rotate(45deg);
    }
    
    /* 案例横向滚动 */
    .cases-scroll {
      display: flex;
      gap: 24px;
      overflow-x: auto;
      padding-bottom: 16px;
      scrollbar-width: none;
      -ms-overflow-style: none;
    }
    .cases-scroll::-webkit-scrollbar {
      display: none;
    }
    .case-card {
      min-width: 300px;
      flex-shrink: 0;
      background: white;
      border-radius: var(--radius-md);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: transform 0.2s;
    }
    .case-card:hover {
      transform: translateY(-4px);
    }
    .case-img {
      height: 180px;
      object-fit: cover;
      width: 100%;
    }
    
    /* 响应式 */
    @media (max-width: 1024px) {
      .section { padding-top: 80px; padding-bottom: 80px; }
      .section-title { font-size: 32px; }
    }
    @media (max-width: 768px) {
      :root { --section-padding: 60px; }
      .navbar { display: none; }
      .mobile-nav { display: flex; }
      .section-title { font-size: 28px; }
      .hero-flex { flex-direction: column; text-align: center; }
      .grid-3, .grid-2 { grid-template-columns: 1fr; }
      .cases-scroll { flex-direction: column; }
      .case-card { min-width: auto; }
      .footer-grid { grid-template-columns: repeat(2,1fr); }
    }
    @media (max-width: 520px) {
      .container { padding: 0 20px; }
      .hero-title { font-size: 32px; }
      .btn { padding: 12px 24px; }
      .footer-grid { grid-template-columns: 1fr; }
    }