/* roulang page: index */
/* 全局设计变量 */
    :root {
      --primary: #1B2A4A;
      --primary-hover: #152238;
      --accent: #FF6B35;
      --success: #00A86B;
      --warning: #FF9F0A;
      --error: #FA5151;
      --text-primary: #1F2329;
      --text-secondary: #86909C;
      --bg-page: #F5F6FA;
      --bg-white: #FFFFFF;
      --border-light: #E8EAED;
      --radius-card: 12px;
      --radius-btn: 8px;
      --shadow-sm: 0 2px 12px rgba(27, 42, 74, 0.06);
      --shadow-hover: 0 4px 20px rgba(27, 42, 74, 0.12);
      --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      --max-width: 1200px;
      --nav-height: 64px;
    }

    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }

    html {
      scroll-behavior: smooth;
      scroll-padding-top: var(--nav-height);
    }

    body {
      font-family: var(--font-sans);
      background-color: var(--bg-page);
      color: var(--text-primary);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }

    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 排版 */
    h1, h2, h3 {
      font-weight: 600;
      letter-spacing: -0.02em;
    }

    h2 {
      font-size: 32px;
      line-height: 1.3;
      margin-bottom: 24px;
    }

    h3 {
      font-size: 20px;
      line-height: 1.4;
      font-weight: 600;
    }

    p {
      color: var(--text-secondary);
    }

    /* 按钮系统 */
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      font-weight: 600;
      border-radius: var(--radius-btn);
      transition: all 200ms ease-out;
      cursor: pointer;
      text-decoration: none;
      border: 1.5px solid transparent;
      padding: 14px 32px;
      font-size: 16px;
      line-height: 1.2;
      background: transparent;
      white-space: nowrap;
    }

    .btn-primary {
      background-color: var(--primary);
      color: white;
      border-color: var(--primary);
    }

    .btn-primary:hover {
      background-color: var(--primary-hover);
      border-color: var(--primary-hover);
      box-shadow: 0 8px 18px rgba(27, 42, 74, 0.25);
      transform: translateY(-1px);
    }

    .btn-primary:active {
      transform: scale(0.97);
    }

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

    .btn-outline:hover {
      background-color: rgba(27, 42, 74, 0.08);
      border-color: var(--primary);
    }

    .btn-light {
      background: white;
      color: var(--primary);
      border-color: white;
      font-weight: 600;
    }

    .btn-light:hover {
      background: rgba(255,255,255,0.9);
      box-shadow: 0 8px 20px rgba(0,0,0,0.1);
    }

    .btn-outline-light {
      background: transparent;
      border-color: rgba(255,255,255,0.8);
      color: white;
    }

    .btn-outline-light:hover {
      background: rgba(255,255,255,0.15);
      border-color: white;
    }

    /* 导航 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--nav-height);
      background: rgba(255, 255, 255, 0.88);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      z-index: 100;
      border-bottom: 1px solid transparent;
      transition: box-shadow 200ms ease;
    }

    .site-header.scrolled {
      box-shadow: 0 1px 8px rgba(0, 0, 0, 0.04);
      border-bottom-color: var(--border-light);
    }

    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 100%;
    }

    .logo {
      font-size: 20px;
      font-weight: 700;
      color: var(--primary);
      text-decoration: none;
      letter-spacing: -0.02em;
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
    }

    .nav-links a {
      color: var(--text-primary);
      text-decoration: none;
      font-weight: 500;
      font-size: 16px;
      transition: color 200ms;
      position: relative;
    }

    .nav-links a:hover,
    .nav-links a.active {
      color: var(--primary);
    }

    .nav-links a.active::after {
      content: '';
      position: absolute;
      bottom: -8px;
      left: 0;
      width: 100%;
      height: 2px;
      background: var(--primary);
    }

    .mobile-menu-btn {
      display: none;
      background: none;
      border: none;
      flex-direction: column;
      gap: 6px;
      cursor: pointer;
      padding: 8px;
    }

    .mobile-menu-btn span {
      display: block;
      width: 24px;
      height: 2px;
      background: var(--primary);
      border-radius: 2px;
      transition: all 200ms;
    }

    /* 移动端侧滑菜单 */
    .mobile-nav {
      position: fixed;
      top: 0;
      right: 0;
      width: 75%;
      max-width: 320px;
      height: 100vh;
      background: white;
      box-shadow: -8px 0 24px rgba(0,0,0,0.1);
      transform: translateX(100%);
      transition: transform 300ms ease;
      z-index: 200;
      display: flex;
      flex-direction: column;
      padding: 24px;
    }

    .mobile-nav.open {
      transform: translateX(0);
    }

    .mobile-nav a {
      padding: 16px 0;
      font-size: 18px;
      font-weight: 500;
      color: var(--text-primary);
      text-decoration: none;
      border-bottom: 1px solid var(--border-light);
    }

    .overlay {
      position: fixed;
      inset: 0;
      background: rgba(0,0,0,0.3);
      z-index: 150;
      display: none;
    }

    .overlay.show {
      display: block;
    }

    /* 区块间距 */
    section {
      padding: 80px 0;
    }

    /* Hero */
    .hero {
      padding: 120px 0 80px;
      background-color: var(--bg-page);
      position: relative;
      overflow: hidden;
    }

    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 60px;
      align-items: center;
    }

    .hero-content h1 {
      font-size: 48px;
      font-weight: 700;
      line-height: 1.2;
      color: var(--primary);
      margin-bottom: 20px;
    }

    .hero-content p {
      font-size: 16px;
      color: var(--text-secondary);
      margin-bottom: 32px;
      max-width: 480px;
    }

    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }

    .hero-image {
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      border-radius: 24px;
      height: 380px;
      box-shadow: var(--shadow-sm);
      position: relative;
    }

    /* 痛点卡片 */
    .pain-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .pain-item {
      background: #F8F9FB;
      border-radius: 8px;
      padding: 20px 24px;
      display: flex;
      gap: 16px;
      align-items: center;
      transition: all 200ms;
    }

    .pain-icon {
      font-size: 24px;
      color: var(--primary);
    }

    /* 解决方案卡片 */
    .cards-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
    }

    .service-card {
      background: var(--bg-white);
      border-radius: var(--radius-card);
      padding: 32px;
      box-shadow: var(--shadow-sm);
      transition: all 200ms ease-out;
      display: flex;
      flex-direction: column;
    }

    .service-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }

    .card-icon {
      width: 64px;
      height: 64px;
      background: #E8ECF4;
      border-radius: 12px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--primary);
      font-size: 28px;
      margin-bottom: 20px;
    }

    .service-card h3 {
      margin-bottom: 12px;
    }

    .card-link {
      margin-top: auto;
      color: var(--primary);
      font-weight: 500;
      text-decoration: none;
      display: inline-flex;
      align-items: center;
      gap: 4px;
      transition: gap 200ms;
    }

    .card-link:hover {
      gap: 8px;
    }

    /* 数据区 */
    .stats-row {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      text-align: center;
      background: white;
      border-radius: 0;
      padding: 40px 0;
    }

    .stat-number {
      font-size: 56px;
      font-weight: 700;
      line-height: 1.1;
      color: var(--primary);
    }

    .stat-label {
      font-size: 16px;
      color: var(--text-secondary);
      margin-top: 8px;
    }

    .stat-item:nth-child(even) .stat-number {
      color: var(--accent);
    }

    /* 证言 */
    .testimonials-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .testimonial-card {
      background: white;
      border-radius: var(--radius-card);
      padding: 32px;
      box-shadow: var(--shadow-sm);
    }

    .quote-icon {
      font-size: 48px;
      color: rgba(27,42,74,0.1);
      line-height: 1;
    }

    .testimonial-text {
      margin: 16px 0 24px;
    }

    .author {
      display: flex;
      align-items: center;
      gap: 12px;
    }

    .avatar {
      width: 48px;
      height: 48px;
      background: #ddd;
      border-radius: 50%;
    }

    /* FAQ */
    .faq-list {
      max-width: 720px;
      margin: 0 auto;
      border-top: 1px solid var(--border-light);
    }

    .faq-item {
      border-bottom: 1px solid var(--border-light);
    }

    .faq-question {
      width: 100%;
      background: none;
      border: none;
      padding: 20px 0;
      display: flex;
      justify-content: space-between;
      font-weight: 600;
      font-size: 16px;
      cursor: pointer;
      color: var(--text-primary);
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 300ms ease;
      color: var(--text-secondary);
      padding-bottom: 0;
    }

    .faq-item.open .faq-answer {
      max-height: 200px;
      padding-bottom: 20px;
    }

    /* 终局CTA */
    .cta-section {
      background: var(--primary);
      padding: 80px 0;
      text-align: center;
    }

    .cta-section h2 {
      color: white;
    }

    .cta-sub {
      color: rgba(255,255,255,0.8);
      margin-bottom: 32px;
    }

    /* 页脚 */
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1.5fr;
      gap: 40px;
      padding: 60px 0 40px;
    }

    .footer-col h4 {
      margin-bottom: 16px;
      font-weight: 600;
    }

    .footer-col a {
      display: block;
      color: var(--text-secondary);
      text-decoration: none;
      margin-bottom: 10px;
      font-size: 14px;
    }

    .copyright {
      text-align: center;
      padding: 24px 0;
      font-size: 14px;
      color: var(--text-secondary);
      border-top: 1px solid var(--border-light);
    }

    @media (max-width: 1024px) {
      .cards-grid { grid-template-columns: repeat(2, 1fr); }
      .testimonials-grid { grid-template-columns: 1fr; }
    }

    @media (max-width: 768px) {
      .nav-links { display: none; }
      .mobile-menu-btn { display: flex; }
      .hero-grid { grid-template-columns: 1fr; }
      .hero-image { height: 240px; }
      .pain-grid, .cards-grid, .stats-row, .footer-grid {
        grid-template-columns: 1fr;
      }
      h2 { font-size: 26px; }
      .hero-content h1 { font-size: 32px; }
    }