/* roulang page: index */
/* :root 设计变量 */
    :root {
      --primary: #0A1F3F;
      --secondary: #E85D2C;
      --secondary-dark: #C94A1E;
      --bg-light: #F5F7FA;
      --card-bg: #FFFFFF;
      --text-dark: #0A1F3F;
      --text-body: #333333;
      --text-muted: #6B7280;
      --white: #FFFFFF;
      --glass-bg: rgba(255,255,255,0.08);
      --glass-border: rgba(255,255,255,0.15);
      --radius-sm: 8px;
      --radius-md: 12px;
      --radius-lg: 16px;
      --shadow-card: 0 2px 12px rgba(0,0,0,0.06);
      --shadow-card-hover: 0 6px 20px rgba(0,0,0,0.1);
      --shadow-glass: 0 8px 32px rgba(0,0,0,0.25);
      --glow: 0 0 20px rgba(232,93,44,0.4);
      --transition: 0.2s ease;
      --font-stack: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
    }
    /* 全局重置 */
    *, *::before, *::after {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }
    html {
      scroll-behavior: smooth;
      font-size: 16px;
    }
    body {
      font-family: var(--font-stack);
      background-color: var(--bg-light);
      color: var(--text-body);
      line-height: 1.7;
      -webkit-font-smoothing: antialiased;
      -moz-osx-font-smoothing: grayscale;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition);
    }
    button, .btn {
      cursor: pointer;
      font-family: inherit;
      border: none;
      outline: none;
      transition: all var(--transition);
    }
    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }
    /* 玻璃拟态卡片（深色背景专用） */
    .glass-card {
      background: var(--glass-bg);
      backdrop-filter: blur(16px);
      -webkit-backdrop-filter: blur(16px);
      border: 1px solid var(--glass-border);
      border-radius: var(--radius-lg);
      box-shadow: var(--shadow-glass);
      color: var(--white);
    }
    /* 浅色卡片 */
    .card-light {
      background: var(--card-bg);
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-card);
      transition: box-shadow var(--transition);
    }
    .card-light:hover {
      box-shadow: var(--shadow-card-hover);
    }
    /* 按钮系统 */
    .btn-primary {
      background: var(--secondary);
      color: var(--white);
      border-radius: var(--radius-md);
      padding: 14px 32px;
      font-weight: 600;
      font-size: 18px;
      letter-spacing: 0.5px;
      box-shadow: 0 4px 12px rgba(232,93,44,0.3);
      display: inline-flex;
      align-items: center;
      justify-content: center;
      transition: all 0.25s ease;
    }
    .btn-primary:hover {
      background: var(--secondary-dark);
      box-shadow: var(--glow);
      transform: scale(1.02);
    }
    .btn-primary:active {
      transform: scale(0.98);
    }
    .btn-ghost {
      background: transparent;
      border: 2px solid var(--secondary);
      color: var(--secondary);
      border-radius: var(--radius-md);
      padding: 14px 32px;
      font-weight: 600;
      font-size: 18px;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      transition: all 0.25s ease;
    }
    .btn-ghost:hover {
      background: var(--secondary);
      color: var(--white);
    }
    .btn-lg {
      padding: 18px 40px;
      font-size: 20px;
    }
    /* 导航 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      background: rgba(10,31,63,0.92);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      border-bottom: 1px solid rgba(255,255,255,0.15);
      padding: 0 24px;
      transition: background 0.3s;
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: 1200px;
      margin: 0 auto;
      height: 70px;
    }
    .brand {
      font-size: 20px;
      font-weight: 700;
      color: var(--white);
      letter-spacing: 0.3px;
    }
    .nav-links {
      display: flex;
      gap: 32px;
      align-items: center;
    }
    .nav-links a {
      color: rgba(255,255,255,0.85);
      font-weight: 500;
      font-size: 16px;
      transition: color 0.2s;
    }
    .nav-links a:hover {
      color: var(--secondary);
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      background: transparent;
      border: none;
      cursor: pointer;
      padding: 8px;
    }
    .hamburger span {
      width: 26px;
      height: 2.5px;
      background: var(--white);
      border-radius: 2px;
      transition: all 0.3s;
    }
    /* 移动端菜单 */
    .mobile-menu {
      position: fixed;
      top: 70px;
      left: 0;
      width: 100%;
      background: var(--primary);
      backdrop-filter: blur(12px);
      display: none;
      flex-direction: column;
      padding: 24px;
      gap: 20px;
      z-index: 999;
    }
    .mobile-menu a {
      color: var(--white);
      font-size: 18px;
      font-weight: 500;
      padding: 8px 0;
      border-bottom: 1px solid rgba(255,255,255,0.15);
    }
    .mobile-menu.active {
      display: flex;
    }
    /* 板块间距 */
    section {
      padding: 80px 0;
    }
    @media (max-width: 768px) {
      section {
        padding: 48px 0;
      }
      .nav-links {
        display: none;
      }
      .hamburger {
        display: flex;
      }
    }
    /* Hero */
    .hero {
      background-color: var(--primary);
      color: var(--white);
      padding-top: 120px;
      padding-bottom: 80px;
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 48px;
      align-items: center;
    }
    .hero-content h1 {
      font-size: 42px;
      font-weight: 700;
      line-height: 1.3;
      margin-bottom: 20px;
    }
    .hero-content p {
      font-size: 18px;
      color: rgba(255,255,255,0.7);
      margin-bottom: 32px;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .hero-image img {
      border-radius: var(--radius-lg);
      box-shadow: 0 20px 40px rgba(0,0,0,0.4);
    }
    /* 痛点区 */
    .pain-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      margin-top: 32px;
    }
    .pain-card {
      background: var(--card-bg);
      border-radius: var(--radius-md);
      padding: 28px 20px;
      box-shadow: var(--shadow-card);
      border-left: 4px solid var(--secondary);
      transition: all 0.25s;
    }
    .pain-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-card-hover);
    }
    .pain-icon {
      font-size: 28px;
      color: var(--secondary);
      margin-bottom: 16px;
    }
    .pain-card h3 {
      font-size: 20px;
      font-weight: 600;
      color: var(--text-dark);
      margin-bottom: 8px;
    }
    /* 解决方案媒体对象 */
    .solution-row {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 48px;
      align-items: center;
    }
    .solution-image img {
      border-radius: var(--radius-lg);
      box-shadow: var(--shadow-card);
    }
    .solution-list {
      display: flex;
      flex-direction: column;
      gap: 24px;
    }
    .solution-item {
      display: flex;
      gap: 16px;
      align-items: flex-start;
    }
    .solution-item i {
      font-size: 24px;
      color: var(--secondary);
      margin-top: 4px;
    }
    /* 成果数据 */
    .stats-section {
      background: var(--primary);
    }
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .stat-card {
      text-align: center;
      padding: 36px 20px;
    }
    .stat-number {
      font-size: 48px;
      font-weight: 700;
      color: var(--secondary);
      margin-bottom: 12px;
    }
    .stat-label {
      color: rgba(255,255,255,0.8);
      font-size: 18px;
    }
    /* 证言 */
    .testimonial-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      margin-top: 32px;
    }
    .testimonial-card {
      background: var(--card-bg);
      border-radius: var(--radius-md);
      padding: 28px;
      box-shadow: var(--shadow-card);
      position: relative;
    }
    .testimonial-card .quote-icon {
      color: var(--secondary);
      font-size: 24px;
      margin-bottom: 12px;
    }
    .testimonial-text {
      font-style: italic;
      margin-bottom: 16px;
      color: var(--text-body);
    }
    .testimonial-author {
      font-weight: 600;
      color: var(--text-dark);
    }
    /* CTA */
    .cta-section {
      background: var(--primary);
      text-align: center;
      color: var(--white);
    }
    .cta-section h2 {
      font-size: 32px;
      margin-bottom: 16px;
    }
    .trust-signal {
      color: rgba(255,255,255,0.75);
      margin: 16px 0 24px;
    }
    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 32px auto 0;
      display: flex;
      flex-direction: column;
      gap: 12px;
    }
    .faq-item {
      background: var(--card-bg);
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-card);
      overflow: hidden;
    }
    .faq-question {
      width: 100%;
      background: transparent;
      padding: 20px 24px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      font-size: 18px;
      color: var(--text-dark);
      transition: background 0.2s;
    }
    .faq-question:hover {
      background: #F0F2F5;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease;
      padding: 0 24px;
      color: var(--text-body);
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-bottom: 20px;
    }
    .faq-icon {
      transition: transform 0.3s;
    }
    .faq-item.active .faq-icon {
      transform: rotate(45deg);
    }
    /* 页脚 */
    .footer {
      background: #0A1F3F;
      color: rgba(255,255,255,0.7);
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 32px;
      margin-bottom: 40px;
    }
    .footer h4 {
      color: var(--white);
      margin-bottom: 16px;
      font-weight: 600;
    }
    .footer a {
      color: rgba(255,255,255,0.7);
      display: block;
      margin-bottom: 8px;
    }
    .footer a:hover {
      color: var(--secondary);
    }
    .copyright {
      border-top: 1px solid rgba(255,255,255,0.15);
      padding-top: 24px;
      text-align: center;
      font-size: 14px;
    }
    /* 响应式 */
    @media (max-width: 1024px) {
      .hero-grid, .solution-row {
        grid-template-columns: 1fr;
        gap: 32px;
      }
      .hero-image {
        order: -1;
      }
    }
    @media (max-width: 768px) {
      .pain-grid, .stats-grid, .testimonial-grid {
        grid-template-columns: 1fr;
      }
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
      .hero-content h1 {
        font-size: 32px;
      }
      .btn-primary, .btn-ghost {
        width: 100%;
        justify-content: center;
      }
    }
    @media (max-width: 520px) {
      .footer-grid {
        grid-template-columns: 1fr;
      }
    }