/* roulang page: index */
:root {
      --primary: #1E5AAB;
      --primary-dark: #164A8A;
      --primary-light: rgba(30, 90, 171, 0.08);
      --secondary: #0F3B6E;
      --accent: #E8A817;
      --bg-white: #FFFFFF;
      --bg-light: #F8FAFC;
      --text-primary: #1E293B;
      --text-secondary: #64748B;
      --border: #E2E8F0;
      --border-light: #E5E7EB;
      --shadow-sm: 0 2px 8px rgba(0,0,0,0.04);
      --shadow-md: 0 8px 24px rgba(0,0,0,0.08);
      --shadow-nav: 0 2px 8px rgba(0,0,0,0.06);
      --radius-btn: 6px;
      --radius-card: 12px;
      --radius-img: 16px;
      --radius-lg: 8px;
      --transition: 0.2s ease;
      --max-width: 1200px;
      --nav-height: 72px;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Inter", system-ui, -apple-system, sans-serif;
    }

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

    html {
      scroll-behavior: smooth;
    }

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

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

    a {
      text-decoration: none;
      color: inherit;
      transition: color var(--transition);
    }

    ul {
      list-style: none;
    }

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

    /* 导航 */
    .site-header {
      position: sticky;
      top: 0;
      z-index: 50;
      background: var(--bg-white);
      border-bottom: 1px solid var(--border);
      height: var(--nav-height);
      transition: box-shadow var(--transition);
      display: flex;
      align-items: center;
    }

    .site-header.scrolled {
      box-shadow: var(--shadow-nav);
    }

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

    .logo {
      display: flex;
      align-items: center;
      gap: 10px;
      font-weight: 700;
      font-size: 20px;
      color: var(--primary);
      letter-spacing: 0.5px;
    }

    .logo-icon {
      width: 36px;
      height: 36px;
      background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
      border-radius: 8px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: white;
      font-size: 18px;
      position: relative;
    }

    .logo-icon::after {
      content: "⚡";
      font-size: 20px;
    }

    .nav-menu {
      display: flex;
      align-items: center;
      gap: 28px;
    }

    .nav-menu a {
      font-size: 15px;
      font-weight: 500;
      color: var(--text-secondary);
      padding: 8px 0;
      position: relative;
      white-space: nowrap;
    }

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

    .nav-menu a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary);
      transition: width 0.2s;
    }

    .nav-menu a:hover::after,
    .nav-menu a.active::after {
      width: 100%;
    }

    .btn-primary {
      background: var(--primary);
      color: white;
      font-weight: 600;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      display: inline-flex;
      align-items: center;
      justify-content: center;
      transition: background var(--transition), transform 0.1s;
      border: none;
      cursor: pointer;
      font-size: 16px;
      white-space: nowrap;
    }

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

    .btn-outline {
      background: transparent;
      border: 1.5px solid var(--primary);
      color: var(--primary);
      font-weight: 600;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      display: inline-flex;
      align-items: center;
      justify-content: center;
      transition: background var(--transition);
      cursor: pointer;
      font-size: 16px;
    }

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

    .btn-large {
      padding: 16px 40px;
      border-radius: var(--radius-lg);
      font-size: 18px;
    }

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

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

    /* 通用板块 */
    section {
      padding: 80px 0;
    }

    .section-title {
      font-size: 32px;
      font-weight: 600;
      line-height: 1.3;
      color: var(--text-primary);
      margin-bottom: 16px;
      text-align: center;
    }

    .section-subtitle {
      color: var(--text-secondary);
      text-align: center;
      max-width: 700px;
      margin: 0 auto 48px;
      font-size: 18px;
    }

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

    /* Hero */
    .hero {
      padding: 60px 0 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: 1.2;
      color: var(--text-primary);
      margin-bottom: 20px;
    }

    .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-image {
      background: url('/assets/images/coverpic/cover-1.webp') center/cover no-repeat;
      border-radius: var(--radius-img);
      min-height: 380px;
      position: relative;
      box-shadow: 0 20px 35px rgba(0,0,0,0.08);
    }

    .hero-image::after {
      content: '';
      position: absolute;
      inset: 0;
      background: rgba(255,255,255,0.1);
      border-radius: var(--radius-img);
    }

    /* 痛点卡片 */
    .cards-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 32px;
    }

    .pain-card {
      background: var(--bg-white);
      border-radius: var(--radius-card);
      padding: 28px 24px;
      box-shadow: var(--shadow-sm);
      transition: all 0.3s ease;
      text-align: left;
    }

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

    .pain-icon {
      font-size: 32px;
      margin-bottom: 18px;
      color: var(--primary);
    }

    .pain-card h3 {
      font-size: 20px;
      font-weight: 600;
      margin-bottom: 10px;
    }

    .pain-card p {
      color: var(--text-secondary);
      font-size: 15px;
    }

    /* 解决方案左右交替 */
    .solution-row {
      display: flex;
      align-items: center;
      gap: 60px;
      margin-bottom: 80px;
    }

    .solution-row.reverse {
      flex-direction: row-reverse;
    }

    .solution-text {
      flex: 1;
    }

    .solution-text h3 {
      font-size: 26px;
      font-weight: 600;
      margin-bottom: 16px;
    }

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

    .solution-list {
      list-style: none;
    }

    .solution-list li {
      display: flex;
      align-items: center;
      gap: 10px;
      margin-bottom: 10px;
      font-weight: 500;
      color: var(--text-primary);
    }

    .solution-list li::before {
      content: "✓";
      color: var(--primary);
      font-weight: 700;
    }

    .solution-image {
      flex: 1;
      border-radius: var(--radius-img);
      overflow: hidden;
    }

    .solution-image img {
      width: 100%;
      height: auto;
      object-fit: cover;
      border-radius: var(--radius-img);
    }

    .learn-more {
      color: var(--primary);
      font-weight: 600;
      border-bottom: 2px solid var(--primary);
      display: inline-block;
      margin-top: 8px;
    }

    .learn-more:hover {
      color: var(--primary-dark);
    }

    /* 数据卡片 */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 32px;
    }

    .stat-card {
      text-align: center;
      padding: 24px 16px;
      border-bottom: 3px solid var(--primary);
      transition: background 0.2s;
      background: transparent;
    }

    .stat-card:hover {
      background: var(--bg-light);
    }

    .stat-number {
      font-size: 48px;
      font-weight: 700;
      color: var(--primary);
      line-height: 1.2;
    }

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

    /* 证言 */
    .testimonials-scroll {
      display: flex;
      gap: 24px;
      overflow-x: auto;
      padding-bottom: 16px;
      scroll-snap-type: x mandatory;
    }

    .testimonial-card {
      min-width: 320px;
      background: var(--bg-white);
      border-left: 4px solid var(--primary);
      padding: 24px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      scroll-snap-align: start;
      transition: all 0.3s;
      flex: 0 0 auto;
    }

    .testimonial-card:hover {
      box-shadow: var(--shadow-md);
    }

    .testimonial-text {
      font-style: italic;
      color: var(--text-primary);
      margin-bottom: 16px;
    }

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

    .avatar-placeholder {
      width: 48px;
      height: 48px;
      background: #F1F5F9;
      border-radius: 50%;
      background-image: url('/assets/images/coverpic/cover-3.webp');
      background-size: cover;
    }

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

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

    .faq-question {
      display: flex;
      justify-content: space-between;
      align-items: center;
      padding: 18px 0;
      cursor: pointer;
      font-weight: 600;
      font-size: 18px;
      transition: background 0.2s;
    }

    .faq-question:hover {
      background: #F8FAFC;
    }

    .faq-icon {
      font-size: 20px;
      color: var(--primary);
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      color: var(--text-secondary);
    }

    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-bottom: 18px;
    }

    .faq-item.active .faq-icon {
      content: "−";
    }

    /* CTA band */
    .cta-band {
      background: rgba(30,90,171,0.05);
      text-align: center;
      padding: 70px 0;
    }

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

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

    .footer-logo {
      font-size: 22px;
      font-weight: 700;
      color: white;
      margin-bottom: 12px;
    }

    .footer-desc {
      color: #94A3B8;
      line-height: 1.6;
    }

    .footer-heading {
      color: white;
      font-weight: 600;
      margin-bottom: 20px;
    }

    .footer-links li {
      margin-bottom: 12px;
    }

    .footer-links a {
      color: #CBD5E1;
      transition: color 0.2s;
    }

    .footer-links a:hover {
      color: var(--primary);
    }

    .copyright {
      border-top: 1px solid #334155;
      padding-top: 24px;
      text-align: center;
      color: #94A3B8;
      font-size: 14px;
    }

    @media (max-width: 1024px) {
      .hero-grid {
        grid-template-columns: 1fr;
        gap: 32px;
      }
      .cards-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .stats-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }

    @media (max-width: 768px) {
      .hamburger {
        display: flex;
      }

      .nav-menu {
        position: fixed;
        top: var(--nav-height);
        left: 0;
        right: 0;
        background: white;
        flex-direction: column;
        padding: 24px;
        gap: 20px;
        display: none;
        box-shadow: var(--shadow-md);
      }

      .nav-menu.open {
        display: flex;
      }

      .solution-row, .solution-row.reverse {
        flex-direction: column;
      }

      .cards-grid {
        grid-template-columns: 1fr;
      }

      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }

      section {
        padding: 48px 0;
      }

      .hero-content h1 {
        font-size: 32px;
      }

      .section-title {
        font-size: 26px;
      }
    }

    @media (max-width: 520px) {
      .stats-grid {
        grid-template-columns: 1fr;
      }
      .footer-grid {
        grid-template-columns: 1fr;
      }
    }