/* roulang page: index */
:root {
      --primary: #0057B3;
      --primary-hover: #003D80;
      --accent: #FF6B00;
      --accent-hover: #CC5500;
      --bg-light: #F8F9FA;
      --bg-white: #FFFFFF;
      --bg-dark: #1A1C20;
      --text-heading: #111111;
      --text-body: #4A4A4A;
      --text-muted: #6C757D;
      --text-on-dark: #FFFFFF;
      --text-dark-secondary: #E9ECEF;
      --border-light: rgba(0,0,0,0.05);
      --shadow-sm: 0 4px 12px rgba(0,0,0,0.04);
      --shadow-md: 0 12px 30px rgba(0,0,0,0.08);
      --radius-md: 12px;
      --radius-btn: 8px;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial, sans-serif;
      --transition: all 0.25s ease;
      --max-width: 1200px;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    html {
      scroll-behavior: smooth;
      font-size: 16px;
    }
    body {
      font-family: var(--font-sans);
      line-height: 1.7;
      color: var(--text-body);
      background-color: var(--bg-white);
      -webkit-font-smoothing: antialiased;
    }
    .container {
      max-width: var(--max-width);
      margin-left: auto;
      margin-right: auto;
      padding: 0 24px;
      width: 100%;
    }
    h1, h2, h3, h4 {
      color: var(--text-heading);
      font-weight: 600;
      line-height: 1.3;
    }
    h1 {
      font-size: 3rem;
      font-weight: 700;
      letter-spacing: -0.5px;
    }
    h2 {
      font-size: 2.25rem;
      margin-bottom: 0.75rem;
    }
    h3 {
      font-size: 1.25rem;
    }
    p {
      color: var(--text-body);
      margin-bottom: 1rem;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition);
    }
    img {
      max-width: 100%;
      display: block;
      height: auto;
    }
    button, .btn {
      cursor: pointer;
      font-family: inherit;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      font-weight: 600;
      border-radius: var(--radius-btn);
      transition: var(--transition);
      border: none;
      white-space: nowrap;
    }
    .btn-primary {
      background-color: var(--accent);
      color: white;
      padding: 12px 32px;
      box-shadow: 0 4px 10px rgba(255,107,0,0.2);
      border: none;
      border-radius: var(--radius-btn);
    }
    .btn-primary:hover {
      background-color: var(--accent-hover);
      transform: scale(1.02);
      box-shadow: 0 8px 16px rgba(255,107,0,0.25);
    }
    .btn-secondary {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
      padding: 12px 32px;
      border-radius: var(--radius-btn);
    }
    .btn-secondary:hover {
      background: var(--primary);
      color: white;
      border-color: var(--primary);
      transform: scale(1.01);
    }
    section {
      padding: 5rem 0;
    }
    .bg-light {
      background-color: var(--bg-light);
    }
    .bg-dark {
      background-color: var(--bg-dark);
    }
    .grid {
      display: grid;
      gap: 1.5rem;
    }
    /* 导航 平台风格 白底模糊 */
    .main-header {
      position: sticky;
      top: 0;
      z-index: 100;
      background: rgba(255,255,255,0.92);
      backdrop-filter: blur(12px);
      border-bottom: 1px solid rgba(0,0,0,0.05);
      padding: 0.8rem 0;
    }
    .nav-bar {
      display: flex;
      align-items: center;
      justify-content: space-between;
      flex-wrap: wrap;
    }
    .logo {
      font-weight: 800;
      font-size: 1.8rem;
      color: var(--primary);
      letter-spacing: -0.3px;
      display: flex;
      align-items: center;
    }
    .logo span {
      color: var(--accent);
      margin-left: 2px;
    }
    .nav-menu {
      display: flex;
      align-items: center;
      gap: 28px;
    }
    .nav-menu a {
      color: var(--text-body);
      font-weight: 500;
      font-size: 1rem;
      padding: 6px 0;
      border-bottom: 2px solid transparent;
    }
    .nav-menu a:hover,
    .nav-menu a.active {
      color: var(--primary);
      border-bottom-color: var(--primary);
    }
    .mobile-toggle {
      display: none;
      background: none;
      border: none;
      font-size: 1.8rem;
      color: var(--text-heading);
    }
    @media (max-width: 768px) {
      .mobile-toggle {
        display: block;
        position: relative;
        z-index: 101;
      }
      .nav-menu {
        display: none;
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100vh;
        background: white;
        flex-direction: column;
        justify-content: center;
        align-items: center;
        gap: 32px;
        font-size: 1.8rem;
        z-index: 100;
      }
      .nav-menu.mobile-active {
        display: flex;
      }
      .nav-cta-mobile {
        display: block;
      }
      h1 {
        font-size: 2.25rem;
      }
      h2 {
        font-size: 1.8rem;
      }
      section {
        padding: 3rem 0;
      }
    }
    /* Hero */
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      align-items: center;
      gap: 3rem;
      min-height: 85vh;
    }
    .hero-content h1 {
      margin-bottom: 1.2rem;
      color: var(--text-heading);
    }
    .hero-content .subtitle {
      font-size: 1.2rem;
      color: var(--text-muted);
      margin-bottom: 2.5rem;
      line-height: 1.6;
    }
    .btn-group {
      display: flex;
      gap: 1.2rem;
      flex-wrap: wrap;
    }
    .hero-visual {
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      border-radius: 28px;
      height: 420px;
      box-shadow: 0 20px 35px rgba(0,87,179,0.12);
      background-blend-mode: overlay;
      background-color: rgba(0,87,179,0.08);
      filter: blur(0.6px);
    }
    @media (max-width: 768px) {
      .hero-grid {
        grid-template-columns: 1fr;
        text-align: center;
        min-height: auto;
      }
      .hero-visual {
        height: 280px;
        order: -1;
      }
      .btn-group {
        justify-content: center;
      }
    }
    /* 痛点卡片 */
    .card-pain {
      background: white;
      border-radius: var(--radius-md);
      padding: 1.8rem;
      display: flex;
      gap: 1.4rem;
      align-items: flex-start;
      transition: var(--transition);
      border: 1px solid transparent;
    }
    .card-pain:hover {
      box-shadow: var(--shadow-sm);
      border-color: #eee;
    }
    .pain-icon {
      font-size: 2.3rem;
      color: var(--accent);
      width: 48px;
      text-align: center;
    }
    /* 解决方案卡片 */
    .solution-grid {
      grid-template-columns: repeat(3, 1fr);
    }
    .card-solution {
      background: white;
      border-radius: var(--radius-md);
      padding: 2rem;
      box-shadow: var(--shadow-sm);
      text-align: center;
      transition: var(--transition);
    }
    .card-solution:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-md);
    }
    .icon-circle {
      background: rgba(0,87,179,0.08);
      width: 64px;
      height: 64px;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      margin: 0 auto 1.5rem;
      color: var(--primary);
      font-size: 2rem;
    }
    /* 数据区 */
    .stats-grid {
      grid-template-columns: repeat(4, 1fr);
      text-align: center;
    }
    .stat-number {
      font-size: 3rem;
      font-weight: 700;
      color: var(--accent);
      line-height: 1.1;
    }
    .stat-label {
      color: var(--text-muted);
      font-size: 0.95rem;
    }
    /* 证言 */
    .testimonial-grid {
      grid-template-columns: repeat(2,1fr);
    }
    .testimonial-card {
      background: white;
      padding: 1.8rem;
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-sm);
      display: flex;
      gap: 1rem;
      align-items: center;
    }
    .avatar-sm {
      width: 56px;
      height: 56px;
      border-radius: 50%;
      object-fit: cover;
      background: #ddd;
    }
    .quote {
      font-style: italic;
      color: var(--text-body);
      margin-bottom: 0.6rem;
    }
    /* FAQ 手风琴 */
    .faq-flex {
      display: flex;
      gap: 2.5rem;
      align-items: flex-start;
    }
    .faq-left {
      flex: 1;
    }
    .faq-right {
      flex: 2;
    }
    .accordion-item {
      border-bottom: 1px solid #e0e0e0;
      padding: 1.2rem 0;
      cursor: pointer;
    }
    .accordion-question {
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      align-items: center;
      color: var(--text-heading);
    }
    .accordion-answer {
      max-height: 0;
      overflow: hidden;
      transition: 0.3s;
      color: var(--text-body);
    }
    .accordion-item.active .accordion-answer {
      max-height: 150px;
      padding-top: 0.8rem;
    }
    .faq-icon {
      font-size: 1.5rem;
      color: var(--primary);
    }
    /* 最终CTA */
    .final-cta {
      background: var(--primary);
      color: white;
      text-align: center;
      border-radius: 28px;
      padding: 4rem 2rem;
      margin: 2rem 0;
    }
    .final-cta h2 {
      color: white;
    }
    /* 页脚 */
    .footer-grid {
      grid-template-columns: 2fr 1fr 1fr 1fr;
      color: var(--text-dark-secondary);
    }
    .footer-logo {
      font-size: 1.6rem;
      font-weight: 700;
      color: white;
    }
    .footer a {
      color: var(--text-dark-secondary);
    }
    .footer a:hover {
      color: var(--accent);
    }
    @media (max-width: 768px) {
      .solution-grid, .stats-grid, .testimonial-grid, .footer-grid {
        grid-template-columns: 1fr;
      }
      .faq-flex {
        flex-direction: column;
      }
    }