/* roulang page: index */
:root {
      --primary: #0A66C2;
      --primary-hover: #084E96;
      --accent: #F5A623;
      --accent-hover: #E5941A;
      --bg: #F8FAFC;
      --surface: #FFFFFF;
      --text-main: #0F172A;
      --text-body: #334155;
      --text-muted: #64748B;
      --border: #E2E8F0;
      --radius-lg: 12px;
      --radius-md: 8px;
      --shadow-card: 0 1px 3px rgba(0,0,0,0.04), 0 1px 2px rgba(0,0,0,0.06);
      --shadow-hover: 0 10px 25px rgba(0,0,0,0.08), 0 4px 10px rgba(0,0,0,0.04);
      --shadow-cta: 0 4px 14px rgba(10,102,194,0.3);
      --transition: all 0.25s ease;
      --max-width: 1200px;
      --spacing-section: 120px;
      --spacing-mobile: 80px;
    }

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

    body {
      font-family: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Noto Sans SC", system-ui, -apple-system, sans-serif;
      background-color: var(--bg);
      color: var(--text-body);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
      -moz-osx-font-smoothing: grayscale;
    }

    .english-number, .stat-num, .num-font {
      font-family: "Inter", "Roboto", "SF Pro Text", sans-serif;
      font-weight: 600;
    }

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

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

    button, .btn {
      cursor: pointer;
      font-family: inherit;
    }

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

    /* 导航 */
    .navbar {
      position: sticky;
      top: 0;
      z-index: 100;
      background: var(--surface);
      box-shadow: 0 1px 3px rgba(0,0,0,0.05);
      backdrop-filter: blur(8px);
      background: rgba(255, 255, 255, 0.96);
      padding: 0 24px;
    }

    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: var(--max-width);
      margin: 0 auto;
      height: 70px;
    }

    .logo {
      display: flex;
      align-items: center;
      gap: 8px;
      font-size: 1.5rem;
      font-weight: 700;
      color: var(--primary);
      letter-spacing: -0.02em;
    }

    .logo i {
      font-size: 1.8rem;
      color: var(--accent);
    }

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

    .nav-link {
      font-weight: 500;
      color: var(--text-body);
      position: relative;
      padding: 4px 0;
      transition: var(--transition);
    }

    .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: 1px;
    }

    .nav-cta {
      background: var(--primary);
      color: white;
      padding: 10px 22px;
      border-radius: var(--radius-md);
      font-weight: 600;
      transition: var(--transition);
      margin-left: 12px;
      box-shadow: var(--shadow-cta);
    }

    .nav-cta:hover {
      background: var(--primary-hover);
      transform: translateY(-1px);
    }

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

    .hamburger span {
      width: 24px;
      height: 2px;
      background: var(--text-main);
      border-radius: 1px;
      transition: var(--transition);
    }

    /* 首屏 Hero */
    .hero {
      background: linear-gradient(135deg, #F8FAFC 0%, #E8F0FE 100%);
      padding: 100px 0 120px;
      position: relative;
      overflow: hidden;
    }

    .hero-container {
      display: flex;
      align-items: center;
      gap: 60px;
    }

    .hero-text {
      flex: 1;
      z-index: 2;
    }

    .hero-text h1 {
      font-size: clamp(2.4rem, 5vw, 3.5rem);
      font-weight: 700;
      line-height: 1.2;
      color: var(--text-main);
      letter-spacing: -0.03em;
      margin-bottom: 20px;
    }

    .hero-text h1 .highlight {
      color: var(--primary);
      position: relative;
    }

    .hero-sub {
      font-size: 1.125rem;
      color: var(--text-body);
      margin-bottom: 32px;
      max-width: 480px;
    }

    .hero-image {
      flex: 1.2;
      background: url('/assets/images/backpic/back-1.webp') no-repeat center/cover;
      border-radius: var(--radius-lg);
      min-height: 360px;
      box-shadow: var(--shadow-hover);
      background-blend-mode: overlay;
      background-color: rgba(10, 102, 194, 0.05);
      display: flex;
      align-items: center;
      justify-content: center;
      color: white;
      font-size: 1.5rem;
    }

    .btn-group {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
      align-items: center;
    }

    .btn-primary {
      background: var(--primary);
      color: white;
      padding: 14px 34px;
      border-radius: var(--radius-md);
      font-weight: 600;
      font-size: 1rem;
      transition: var(--transition);
      box-shadow: var(--shadow-cta);
      border: none;
      display: inline-flex;
      align-items: center;
      gap: 8px;
    }

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

    .btn-secondary {
      background: transparent;
      color: var(--primary);
      padding: 12px 28px;
      border-radius: var(--radius-md);
      font-weight: 600;
        border: 1.5px solid var(--primary);
      transition: var(--transition);
    }

    .btn-secondary:hover {
      background: #E8F0FE;
    }

    .hero-note {
      font-size: 0.85rem;
      color: var(--text-muted);
      margin-top: 12px;
    }

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

    .section-title {
      text-align: center;
      font-size: clamp(2rem, 4vw, 2.5rem);
      font-weight: 600;
      color: var(--text-main);
      margin-bottom: 16px;
    }

    .section-sub {
      text-align: center;
      color: var(--text-muted);
      max-width: 680px;
      margin: 0 auto 56px;
    }

    /* 痛点/方案卡片 */
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }

    .card {
      background: var(--surface);
      border-radius: var(--radius-lg);
      padding: 32px;
      box-shadow: var(--shadow-card);
      transition: var(--transition);
      border: 1px solid var(--border);
    }

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

    .problem-card {
      border-left: 5px solid #F5A623;
      background: #FFF9F0;
    }

    .card-icon {
      font-size: 2rem;
      color: var(--primary);
      margin-bottom: 20px;
    }

    .card h3 {
      font-size: 1.35rem;
      font-weight: 600;
      margin-bottom: 12px;
      color: var(--text-main);
    }

    .asymmetric-grid {
      display: grid;
      grid-template-columns: 1.4fr 0.8fr 0.8fr;
      gap: 24px;
    }

    .big-card {
      background: var(--surface);
      padding: 38px;
      border-radius: var(--radius-lg);
      box-shadow: var(--shadow-card);
    }

    .small-card {
      background: var(--surface);
      padding: 28px;
    }

    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 28px;
    }

    .stat-item {
      text-align: center;
      background: var(--surface);
      padding: 32px 16px;
      border-radius: var(--radius-lg);
      box-shadow: var(--shadow-card);
    }

    .stat-num {
      font-size: 2.8rem;
      font-weight: 700;
      color: var(--accent);
      display: block;
    }

    .testimonial-grid {
      display: grid;
      grid-template-columns: 1.2fr 0.9fr;
      gap: 28px;
    }

    .testimonial-card {
      background: #F1F5F9;
      padding: 32px;
      border-radius: var(--radius-lg);
      position: relative;
    }

    .testimonial-card.main {
      grid-row: span 2;
      background: white;
      box-shadow: var(--shadow-card);
    }

    .quote-icon {
      font-size: 3rem;
      color: #CBD5E1;
      position: absolute;
      top: 16px;
      left: 20px;
    }

    .faq-item {
      border-bottom: 1px solid var(--border);
      background: white;
      margin-bottom: 8px;
      border-radius: 4px;
    }

    .faq-question {
      padding: 20px;
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
      background: var(--surface);
      transition: var(--transition);
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      background: #F8FAFC;
      padding: 0 20px;
    }

    .faq-item.active .faq-answer {
      max-height: 200px;
      padding: 16px 20px;
    }

    .cta-section {
      background: linear-gradient(135deg, #0A66C2 0%, #084E96 100%);
      padding: 80px 0;
      text-align: center;
      color: white;
      border-radius: 24px;
      margin: 60px 24px;
    }

    .footer {
      background: #0F172A;
      color: #CBD5E1;
      padding: 60px 0 30px;
    }

    .footer-grid {
      display: flex;
      justify-content: space-between;
      flex-wrap: wrap;
      gap: 40px;
    }

    .footer-links a {
      display: block;
      margin: 8px 0;
      color: #94A3B8;
    }

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

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

    @media (max-width: 768px) {
      .navbar {
        padding: 0 16px;
      }
      .nav-menu {
        display: none;
        flex-direction: column;
        position: absolute;
        top: 70px;
        left: 0;
        width: 100%;
        background: white;
        box-shadow: var(--shadow-hover);
        padding: 20px;
      }
      .nav-menu.active {
        display: flex;
      }
      .hamburger {
        display: flex;
      }
      .hero-container {
        flex-direction: column;
      }
      .grid-3 {
        grid-template-columns: 1fr;
      }
      .section {
        padding: 80px 0;
      }
    }