/* roulang page: index */
:root {
      --primary: #4E6EF2;
      --primary-hover: #3D5BD9;
      --primary-light: rgba(78, 110, 242, 0.08);
      --primary-glow: rgba(78, 110, 242, 0.25);
      --green: #00B578;
      --orange: #FF9F0A;
      --red: #FA5151;
      --bg-page: #F5F6FA;
      --white: #FFFFFF;
      --text-main: #1F2329;
      --text-secondary: #86909C;
      --border-light: #E5E8EF;
      --shadow-card: 0 2px 8px rgba(0,0,0,0.04), 0 1px 2px rgba(0,0,0,0.02);
      --shadow-card-hover: 0 8px 24px rgba(0,0,0,0.08), 0 2px 4px rgba(0,0,0,0.04);
      --shadow-nav: 0 2px 8px rgba(0,0,0,0.04);
      --radius: 12px;
      --radius-pill: 20px;
      --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      --nav-height: 64px;
      --container-max: 1200px;
      --section-gap: 100px;
      --section-gap-mobile: 70px;
    }

    * {
      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-main);
      line-height: 1.5;
      -webkit-font-smoothing: antialiased;
    }

    img {
      display: block;
      max-width: 100%;
      height: auto;
    }

    a {
      color: inherit;
      text-decoration: none;
    }

    .container {
      width: 100%;
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 导航 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--nav-height);
      background: rgba(255,255,255,0.85);
      backdrop-filter: blur(8px);
      -webkit-backdrop-filter: blur(8px);
      display: flex;
      align-items: center;
      z-index: 100;
      transition: background 200ms ease, box-shadow 200ms ease;
    }

    .header.scrolled {
      background: rgba(255,255,255,0.98);
      box-shadow: var(--shadow-nav);
    }

    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
    }

    .logo {
      display: flex;
      align-items: center;
      gap: 10px;
      font-size: 22px;
      font-weight: 700;
      color: var(--text-main);
      letter-spacing: -0.3px;
    }

    .logo-icon {
      width: 32px;
      height: 32px;
      background: var(--primary);
      border-radius: 8px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: white;
      font-weight: 700;
      font-size: 18px;
      line-height: 1;
    }

    .nav-menu {
      display: flex;
      align-items: center;
      gap: 32px;
      list-style: none;
    }

    .nav-link {
      font-size: 16px;
      font-weight: 500;
      color: var(--text-main);
      transition: color 150ms;
      position: relative;
      padding: 6px 0;
    }

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

    .nav-link.active::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 100%;
      height: 2px;
      background: var(--primary);
      border-radius: 2px;
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: none;
      border: none;
      padding: 8px;
      z-index: 110;
    }

    .hamburger span {
      width: 24px;
      height: 2px;
      background: var(--text-main);
      border-radius: 2px;
      transition: 200ms;
    }

    .mobile-nav {
      display: none;
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: white;
      flex-direction: column;
      justify-content: center;
      align-items: center;
      gap: 28px;
      z-index: 105;
    }

    .mobile-nav a {
      font-size: 20px;
      font-weight: 500;
      color: var(--text-main);
    }

    /* 板块通用 */
    .section {
      padding: var(--section-gap) 0;
    }

    .section-alt {
      background-color: var(--white);
    }

    .section-bg {
      background-color: var(--bg-page);
    }

    .section-title {
      font-size: 32px;
      font-weight: 700;
      line-height: 1.3;
      margin-bottom: 16px;
      color: var(--text-main);
    }

    .section-desc {
      font-size: 16px;
      color: var(--text-secondary);
      max-width: 720px;
      margin: 0 auto 48px;
      line-height: 1.6;
    }

    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      border-radius: var(--radius);
      font-weight: 500;
      cursor: pointer;
      transition: all 150ms ease;
      border: none;
      font-size: 16px;
      padding: 0 24px;
      height: 48px;
      text-decoration: none;
    }

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

    .btn-primary:hover {
      background: var(--primary-hover);
    }

    .btn-primary:active {
      transform: scale(0.98);
    }

    .btn-secondary {
      background: transparent;
      border: 1px solid var(--primary);
      color: var(--primary);
    }

    .btn-secondary:hover {
      background: var(--primary-light);
    }

    .text-link {
      color: var(--primary);
      font-weight: 500;
      font-size: 14px;
      display: inline-flex;
      align-items: center;
      gap: 4px;
    }

    .text-link:hover {
      text-decoration: underline;
    }

    /* Hero */
    .hero {
      min-height: 92vh;
      display: flex;
      align-items: center;
      background: var(--white);
      padding-top: var(--nav-height);
    }

    .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;
      color: var(--text-main);
    }

    .hero-content p {
      font-size: 18px;
      color: var(--text-secondary);
      margin-bottom: 32px;
      line-height: 1.6;
    }

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

    .hero-visual {
      background: #E5E8EF;
      border-radius: 24px;
      overflow: hidden;
      height: 380px;
      display: flex;
      align-items: center;
      justify-content: center;
    }

    .hero-visual img {
      width: 100%;
      height: 100%;
      object-fit: cover;
    }

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

    .pain-card {
      background: var(--white);
      border-radius: var(--radius);
      padding: 32px;
      box-shadow: var(--shadow-card);
      transition: all 200ms;
    }

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

    .pain-icon {
      width: 48px;
      height: 48px;
      background: var(--primary-light);
      border-radius: 12px;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 20px;
      color: var(--primary);
      font-size: 24px;
    }

    .pain-card h3 {
      font-size: 20px;
      font-weight: 600;
      margin-bottom: 8px;
    }

    .pain-card p {
      font-size: 14px;
      color: var(--text-secondary);
      line-height: 1.5;
    }

    /* 方案卡片 */
    .solution-card {
      background: var(--white);
      border-radius: var(--radius);
      overflow: hidden;
      box-shadow: var(--shadow-card);
      transition: all 200ms;
    }

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

    .solution-img {
      aspect-ratio: 16 / 9;
      background: #E5E8EF;
      overflow: hidden;
    }

    .solution-img img {
      width: 100%;
      height: 100%;
      object-fit: cover;
    }

    .solution-text {
      padding: 24px;
    }

    .solution-text h3 {
      font-size: 20px;
      font-weight: 600;
      margin-bottom: 8px;
    }

    .solution-text p {
      font-size: 14px;
      color: var(--text-secondary);
      margin-bottom: 16px;
    }

    /* 数据展示 */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 32px;
      text-align: center;
    }

    .stat-item .stat-number {
      font-size: 36px;
      font-weight: 700;
      color: var(--primary);
      line-height: 1.2;
    }

    .stat-item .stat-label {
      font-size: 14px;
      color: var(--text-secondary);
      margin-top: 6px;
    }

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

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

    .testimonial-quote {
      font-size: 60px;
      color: rgba(0,0,0,0.03);
      position: absolute;
      top: 20px;
      left: 24px;
      line-height: 1;
    }

    .testimonial-text {
      font-size: 16px;
      line-height: 1.6;
      margin-bottom: 24px;
      color: var(--text-main);
      position: relative;
      z-index: 1;
    }

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

    .avatar {
      width: 40px;
      height: 40px;
      background: #E5E8EF;
      border-radius: 50%;
    }

    .author-name {
      font-weight: 600;
      font-size: 14px;
    }

    .author-role {
      font-size: 12px;
      color: var(--text-secondary);
    }

    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }

    .faq-item {
      border-bottom: 1px solid var(--border-light);
      padding: 20px 0;
    }

    .faq-question {
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      font-size: 16px;
      font-weight: 500;
      color: var(--text-main);
      gap: 16px;
    }

    .faq-icon {
      width: 24px;
      height: 24px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--text-secondary);
      transition: 200ms;
      font-size: 20px;
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 300ms ease-out, padding 300ms;
      color: var(--text-secondary);
      font-size: 14px;
      line-height: 1.6;
    }

    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-top: 12px;
    }

    .faq-item.active .faq-icon {
      color: var(--primary);
      transform: rotate(45deg);
    }

    /* CTA表单 */
    .contact-form {
      max-width: 520px;
      margin: 0 auto;
      display: flex;
      flex-direction: column;
      gap: 20px;
    }

    .form-input {
      width: 100%;
      height: 48px;
      border: 1px solid var(--border-light);
      border-radius: var(--radius);
      padding: 0 16px;
      font-size: 16px;
      background: white;
      transition: 150ms;
      font-family: inherit;
    }

    .form-input:focus {
      outline: none;
      border-color: var(--primary);
      box-shadow: 0 0 0 3px rgba(78,110,242,0.15);
    }

    textarea.form-input {
      height: 100px;
      padding: 14px 16px;
      resize: vertical;
    }

    /* 页脚 */
    .footer {
      background: #1F2329;
      color: white;
      padding: 60px 0 30px;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 3fr 2fr 2fr 2fr;
      gap: 40px;
      margin-bottom: 40px;
    }

    .footer-brand p {
      color: #86909C;
      margin-top: 12px;
      font-size: 14px;
    }

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

    .footer-links {
      list-style: none;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }

    .footer-links a {
      color: #86909C;
      font-size: 14px;
    }

    .footer-links a:hover {
      color: white;
    }

    .copyright {
      border-top: 1px solid rgba(255,255,255,0.08);
      padding-top: 24px;
      font-size: 12px;
      color: #86909C;
      text-align: center;
    }

    @media (max-width: 992px) {
      .hero-grid {
        grid-template-columns: 1fr;
      }
      .cards-grid,
      .testimonial-grid {
        grid-template-columns: 1fr 1fr;
      }
      .stats-grid {
        grid-template-columns: 1fr 1fr;
      }
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
    }

    @media (max-width: 768px) {
      :root {
        --nav-height: 56px;
      }
      .nav-menu {
        display: none;
      }
      .hamburger {
        display: flex;
      }
      .mobile-nav.active {
        display: flex;
      }
      .section-title {
        font-size: 28px;
      }
      .hero-content h1 {
        font-size: 34px;
      }
      .cards-grid,
      .testimonial-grid {
        grid-template-columns: 1fr;
      }
      .container {
        padding: 0 16px;
      }
      .section {
        padding: var(--section-gap-mobile) 0;
      }
      .footer-grid {
        grid-template-columns: 1fr;
        gap: 32px;
      }
    }