/* roulang page: index */
:root {
      --primary: #1A5F7A;
      --primary-soft: rgba(26, 95, 122, 0.08);
      --secondary: #0D9488;
      --accent: #0F766E;
      --data-highlight: #0369A1;
      --bg: #F8FAFC;
      --surface: #FFFFFF;
      --text: #1E293B;
      --text-soft: #64748B;
      --border: #E2E8F0;
      --shadow-sm: 0 1px 3px rgba(0,0,0,0.06), 0 1px 2px rgba(0,0,0,0.04);
      --shadow-md: 0 10px 25px -5px rgba(0,0,0,0.08), 0 4px 10px -2px rgba(0,0,0,0.05);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-input: 6px;
      --font-heading: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      --font-body: 'PingFang SC', 'Microsoft YaHei', 'Segoe UI', sans-serif;
      --font-number: 'Inter', 'PingFang SC', sans-serif;
      --max-width: 1200px;
      --header-height: 64px;
    }

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

    body {
      font-family: var(--font-body);
      background-color: var(--bg);
      color: var(--text);
      line-height: 1.6;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }

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

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

    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s ease;
    }

    button {
      font-family: inherit;
      cursor: pointer;
      border: none;
      background: none;
    }

    h1, h2, h3 {
      font-family: var(--font-heading);
      font-weight: 600;
      line-height: 1.3;
    }

    h1 {
      font-weight: 700;
    }

    /* 导航 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--header-height);
      background: rgba(255,255,255,0.92);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      border-bottom: 1px solid rgba(226, 232, 240, 0.6);
      z-index: 100;
      display: flex;
      align-items: center;
    }

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

    .logo {
      display: flex;
      align-items: center;
      gap: 8px;
      font-family: var(--font-heading);
      font-weight: 700;
      font-size: 1.4rem;
      color: var(--primary);
      letter-spacing: 0.5px;
    }

    .logo-icon {
      width: 28px;
      height: 28px;
      background: linear-gradient(135deg, var(--primary), var(--secondary));
      border-radius: 6px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: white;
      font-size: 16px;
    }

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

    .nav-link {
      font-size: 0.95rem;
      font-weight: 500;
      color: #475569;
      padding: 6px 0;
      border-bottom: 2px solid transparent;
      transition: color 0.2s, border-color 0.2s;
    }

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

    .btn-primary-sm {
      background: var(--primary);
      color: white;
      font-weight: 600;
      padding: 10px 22px;
      border-radius: var(--radius-btn);
      font-size: 0.9rem;
      transition: background 0.2s, transform 0.2s;
      display: inline-block;
      text-align: center;
    }

    .btn-primary-sm:hover {
      background: var(--accent);
      transform: translateY(-1px);
    }

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

    .hamburger span {
      width: 24px;
      height: 2px;
      background: var(--text);
      transition: 0.2s;
    }

    .mobile-nav {
      position: fixed;
      top: 0;
      right: -100%;
      width: 75%;
      max-width: 300px;
      height: 100vh;
      background: white;
      box-shadow: -5px 0 20px rgba(0,0,0,0.1);
      padding: 80px 30px 30px;
      display: flex;
      flex-direction: column;
      gap: 28px;
      transition: right 0.3s ease;
      z-index: 105;
    }

    .mobile-nav.open {
      right: 0;
    }

    .mobile-nav .nav-link {
      font-size: 1.1rem;
      border-bottom: none;
    }

    .mobile-cta {
      margin-top: auto;
    }

    /* 通用板块 */
    section {
      padding: 100px 0;
    }

    @media (max-width: 768px) {
      section {
        padding: 70px 0;
      }
    }

    /* Hero */
    .hero {
      padding-top: calc(var(--header-height) + 60px);
      padding-bottom: 80px;
      display: flex;
      align-items: center;
      background: linear-gradient(180deg, #F8FAFC 0%, #FFFFFF 100%);
    }

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

    .hero-content {
      max-width: 540px;
    }

    .hero h1 {
      font-size: 3rem;
      color: var(--text);
      margin-bottom: 1.2rem;
      letter-spacing: -0.5px;
    }

    .hero-sub {
      font-size: 1.1rem;
      color: var(--text-soft);
      margin-bottom: 2rem;
      line-height: 1.7;
    }

    .hero-actions {
      display: flex;
      flex-wrap: wrap;
      align-items: center;
      gap: 16px;
      margin-bottom: 1.5rem;
    }

    .btn-primary {
      background: var(--primary);
      color: white;
      font-weight: 600;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-size: 1rem;
      transition: background 0.2s, transform 0.2s;
      display: inline-block;
    }

    .btn-primary:hover {
      background: var(--accent);
      transform: translateY(-2px);
    }

    .btn-secondary {
      border: 2px solid var(--primary);
      color: var(--primary);
      font-weight: 600;
      padding: 12px 30px;
      border-radius: var(--radius-btn);
      background: transparent;
      transition: background 0.2s, color 0.2s;
    }

    .btn-secondary:hover {
      background: rgba(26,95,122,0.1);
    }

    .trust-badge {
      display: flex;
      align-items: center;
      gap: 20px;
      color: var(--text-soft);
      font-size: 0.9rem;
    }

    .hero-image {
      background: #E2E8F0;
      border-radius: 24px;
      height: 380px;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      box-shadow: 0 20px 30px -15px rgba(0,0,0,0.1);
    }

    /* 痛点 */
    .pain-points {
      background: white;
      text-align: center;
    }

    .pain-grid {
      display: flex;
      flex-wrap: wrap;
      justify-content: center;
      gap: 50px;
      margin-top: 40px;
    }

    .pain-item {
      max-width: 280px;
    }

    .pain-icon {
      font-size: 2.4rem;
      margin-bottom: 16px;
    }

    .pain-item p {
      color: var(--text-soft);
    }

    /* 解决方案卡片 */
    .solution {
      background: var(--bg);
    }

    .cards-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      margin-top: 40px;
    }

    .card {
      background: var(--surface);
      border-radius: var(--radius-card);
      padding: 32px 28px;
      border: 1px solid var(--border);
      box-shadow: var(--shadow-sm);
      transition: all 0.25s ease;
      display: flex;
      flex-direction: column;
    }

    .card:hover {
      box-shadow: var(--shadow-md);
      transform: translateY(-4px);
      border-color: var(--primary);
    }

    .card-icon {
      width: 48px;
      height: 48px;
      background: rgba(13,148,136,0.1);
      border-radius: 12px;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 20px;
      background-image: url('/assets/images/coverpic/cover-1.webp');
      background-size: cover;
    }

    .card h3 {
      font-size: 1.3rem;
      margin-bottom: 12px;
    }

    .card p {
      color: var(--text-soft);
      font-size: 0.95rem;
      margin-bottom: 20px;
      flex: 1;
    }

    .card-link {
      color: var(--primary);
      font-weight: 600;
      font-size: 0.9rem;
      display: inline-flex;
      align-items: center;
      gap: 4px;
    }

    /* 数据条 */
    .results {
      background: #F0F4F8;
    }

    .stats-grid {
      display: flex;
      flex-wrap: wrap;
      justify-content: space-around;
      text-align: center;
      gap: 30px;
    }

    .stat-number {
      font-family: var(--font-number);
      font-size: 2.8rem;
      font-weight: 700;
      color: var(--data-highlight);
    }

    .stat-label {
      color: var(--text-soft);
      font-size: 1rem;
    }

    /* 证言 */
    .testimonials {
      background: white;
    }

    .testimonial-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 24px;
      margin-top: 40px;
    }

    .testimonial-card {
      background: var(--bg);
      padding: 28px;
      border-radius: var(--radius-card);
      display: flex;
      gap: 16px;
      align-items: flex-start;
    }

    .avatar {
      width: 48px;
      height: 48px;
      background: #CBD5E1;
      border-radius: 50%;
      flex-shrink: 0;
    }

    .quote {
      font-style: italic;
      font-size: 0.95rem;
      margin-bottom: 12px;
      color: var(--text);
    }

    .author {
      font-weight: 600;
      font-size: 0.9rem;
    }

    .role {
      color: var(--text-soft);
      font-size: 0.8rem;
    }

    /* FAQ */
    .faq-section {
      background: var(--bg);
    }

    .faq-list {
      max-width: 800px;
      margin: 40px auto 0;
    }

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

    .faq-question {
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      font-size: 1.05rem;
      cursor: pointer;
      color: var(--text);
      transition: color 0.2s;
    }

    .faq-question:hover {
      color: var(--primary);
    }

    .faq-icon {
      font-size: 1.5rem;
      font-weight: 300;
      color: var(--text-soft);
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      color: var(--text-soft);
      padding-right: 30px;
    }

    .faq-item.active .faq-answer {
      max-height: 120px;
      margin-top: 12px;
    }

    .faq-item.active .faq-question {
      color: var(--primary);
    }

    /* CTA */
    .cta-section {
      background: linear-gradient(135deg, #1A5F7A 0%, #0D9488 100%);
      text-align: center;
      color: white;
    }

    .cta-title {
      font-size: 2.4rem;
      font-weight: 700;
      margin-bottom: 16px;
    }

    .cta-desc {
      opacity: 0.9;
      margin-bottom: 32px;
      font-size: 1.1rem;
    }

    .btn-cta {
      background: white;
      color: var(--primary);
      font-weight: 700;
      padding: 16px 40px;
      border-radius: var(--radius-btn);
      font-size: 1.1rem;
      transition: background 0.2s, transform 0.2s;
    }

    .btn-cta:hover {
      background: #f0f9ff;
      transform: translateY(-2px);
    }

    .cta-sub-link {
      margin-top: 20px;
      opacity: 0.8;
      font-size: 0.9rem;
    }

    /* Footer */
    .footer {
      background: #1E293B;
      color: #CBD5E1;
      padding: 60px 0 30px;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }

    .footer-brand p {
      margin-top: 12px;
      font-size: 0.9rem;
    }

    .footer h4 {
      color: white;
      margin-bottom: 16px;
    }

    .footer a {
      display: block;
      margin-bottom: 8px;
      font-size: 0.9rem;
      color: #CBD5E1;
    }

    .footer a:hover {
      color: white;
    }

    .copyright {
      margin-top: 40px;
      padding-top: 20px;
      border-top: 1px solid #334155;
      text-align: center;
      font-size: 0.85rem;
    }

    /* 响应式 */
    @media (max-width: 1024px) {
      .hero-grid {
        grid-template-columns: 1fr;
        gap: 40px;
      }
      .hero-image {
        height: 300px;
      }
      .cards-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
    }

    @media (max-width: 768px) {
      .nav-menu {
        display: none;
      }
      .hamburger {
        display: flex;
      }
      .cards-grid,
      .testimonial-grid {
        grid-template-columns: 1fr;
      }
      .hero h1 {
        font-size: 2.2rem;
      }
      .stats-grid {
        flex-direction: column;
        align-items: center;
      }
    }

    @media (max-width: 520px) {
      .hero-actions {
        flex-direction: column;
        align-items: stretch;
      }
      .btn-primary, .btn-secondary {
        text-align: center;
      }
    }