/* roulang page: index */
:root {
      --primary: #1A5F7A;
      --primary-hover: #134B61;
      --accent: #F39C12;
      --accent-hover: #D68910;
      --bg: #FAFBFD;
      --card-bg: #FFFFFF;
      --light-section: #F0F5F8;
      --dark-section: #0D2E3F;
      --text: #2C3E50;
      --text-secondary: #5A6F7C;
      --text-muted: #7B8A94;
      --border-light: #E5ECF0;
      --shadow-sm: 0 2px 12px rgba(13, 46, 63, 0.06);
      --shadow-md: 0 8px 24px rgba(13, 46, 63, 0.10);
      --radius: 12px;
      --radius-btn: 8px;
      --font-heading: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", system-ui, -apple-system, sans-serif;
      --font-body: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", system-ui, -apple-system, sans-serif;
      --max-width: 1200px;
      --header-height: 72px;
    }

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

    html {
      scroll-behavior: smooth;
      font-size: 16px;
    }

    body {
      font-family: var(--font-body);
      background-color: var(--bg);
      color: var(--text);
      line-height: 1.7;
      -webkit-font-smoothing: antialiased;
      -moz-osx-font-smoothing: grayscale;
    }

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

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

    button, .btn {
      cursor: pointer;
      font-family: var(--font-body);
      border: none;
      outline: none;
      transition: all 0.25s ease;
    }

    .container {
      width: 100%;
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 20px;
    }

    h1, h2, h3, h4 {
      font-family: var(--font-heading);
      font-weight: 600;
      line-height: 1.2;
      color: #1E293B;
    }

    h1 {
      font-size: clamp(2rem, 6vw, 3rem);
      font-weight: 700;
      letter-spacing: -0.5px;
    }

    h2 {
      font-size: clamp(1.75rem, 4.5vw, 2.25rem);
      margin-bottom: 0.75rem;
    }

    h3 {
      font-size: 1.25rem;
    }

    .section-subtitle {
      font-size: 1rem;
      color: var(--text-secondary);
      max-width: 600px;
      margin: 0 auto 2.5rem auto;
    }

    header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--header-height);
      background: rgba(255,255,255,0.92);
      backdrop-filter: blur(8px);
      -webkit-backdrop-filter: blur(8px);
      box-shadow: 0 1px 8px rgba(13, 46, 63, 0.06);
      z-index: 1000;
      display: flex;
      align-items: center;
    }

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

    .logo {
      font-family: var(--font-heading);
      font-size: 1.5rem;
      font-weight: 700;
      color: var(--primary);
      white-space: nowrap;
      display: flex;
      align-items: center;
      gap: 4px;
    }
    .logo span {
      color: var(--accent);
      font-size: 0.9rem;
      font-weight: 500;
      margin-left: 2px;
      background: #FFF7E5;
      padding: 2px 8px;
      border-radius: 20px;
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 2rem;
      list-style: none;
    }

    .nav-links a {
      font-weight: 500;
      color: var(--text);
      font-size: 0.95rem;
      position: relative;
      padding: 4px 0;
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: var(--primary);
    }
    .nav-links a::after {
      content: "";
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary);
      transition: width 0.2s ease;
      border-radius: 1px;
    }
    .nav-links a:hover::after {
      width: 100%;
    }

    .btn-primary {
      background: var(--primary);
      color: white;
      padding: 10px 22px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 0.9rem;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 6px;
      box-shadow: 0 4px 10px rgba(26,95,122,0.2);
      border: 1.5px solid transparent;
    }
    .btn-primary:hover {
      background: var(--primary-hover);
      box-shadow: 0 8px 18px rgba(19,75,97,0.25);
      transform: scale(1.02);
    }

    .btn-accent {
      background: var(--accent);
      color: white;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 0.95rem;
      display: inline-flex;
      align-items: center;
      gap: 6px;
      box-shadow: 0 4px 12px rgba(243,156,18,0.3);
    }
    .btn-accent:hover {
      background: var(--accent-hover);
      box-shadow: 0 8px 20px rgba(214,137,16,0.35);
      transform: scale(1.02);
    }

    .btn-outline {
      background: transparent;
      border: 1.5px solid var(--primary);
      color: var(--primary);
      padding: 10px 22px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 0.9rem;
      display: inline-flex;
      align-items: center;
      gap: 4px;
    }
    .btn-outline:hover {
      background: var(--primary);
      color: white;
      box-shadow: 0 6px 16px rgba(26,95,122,0.15);
    }

    .mobile-menu-btn {
      display: none;
      background: none;
      border: none;
      font-size: 1.5rem;
      color: var(--text);
      padding: 8px;
    }

    .hero {
      min-height: 90vh;
      display: flex;
      align-items: center;
      justify-content: center;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      position: relative;
      margin-top: var(--header-height);
    }
    .hero::before {
      content: "";
      position: absolute;
      inset: 0;
      background: linear-gradient(135deg, rgba(13,46,63,0.8) 0%, rgba(26,95,122,0.7) 100%);
    }
    .hero-content {
      position: relative;
      z-index: 2;
      text-align: center;
      color: white;
      max-width: 750px;
      padding: 0 20px;
    }
    .hero h1 {
      color: white;
      margin-bottom: 1rem;
      font-size: clamp(2.2rem, 7vw, 3.4rem);
      text-shadow: 0 4px 20px rgba(0,0,0,0.3);
    }
    .hero p {
      font-size: 1.1rem;
      opacity: 0.9;
      margin-bottom: 2rem;
      color: rgba(255,255,255,0.9);
    }
    .hero-actions {
      display: flex;
      flex-wrap: wrap;
      gap: 1rem;
      justify-content: center;
    }

    section {
      padding: 5rem 0;
    }

    .section-title {
      text-align: center;
      margin-bottom: 0.5rem;
    }

    .highlight {
      color: var(--accent);
      font-weight: 700;
    }

    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      margin-top: 2rem;
    }

    .card {
      background: var(--card-bg);
      border-radius: var(--radius);
      box-shadow: var(--shadow-sm);
      padding: 2rem 1.5rem;
      transition: all 0.25s ease;
      border-left: 4px solid var(--accent);
    }
    .card:hover {
      box-shadow: var(--shadow-md);
      transform: translateY(-4px);
    }
    .card-icon {
      font-size: 2rem;
      color: var(--accent);
      margin-bottom: 1rem;
    }
    .card h4 {
      font-size: 1.2rem;
      margin-bottom: 0.5rem;
    }
    .card p {
      color: var(--text-secondary);
      font-size: 0.95rem;
    }

    .solution-row {
      display: flex;
      align-items: center;
      gap: 3rem;
      margin-bottom: 4rem;
    }
    .solution-row.reverse {
      flex-direction: row-reverse;
    }
    .solution-text {
      flex: 1;
    }
    .solution-image {
      flex: 1;
      border-radius: var(--radius);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
    }
    .solution-image img {
      width: 100%;
      height: auto;
      object-fit: cover;
    }

    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
      text-align: center;
    }
    .stat-number {
      font-size: 2.8rem;
      font-weight: 700;
      color: var(--accent);
      margin-bottom: 0.25rem;
    }
    .stat-label {
      color: var(--text-muted);
      font-size: 0.9rem;
    }

    .testimonial-cards {
      display: flex;
      gap: 24px;
      overflow-x: auto;
      scroll-snap-type: x mandatory;
      padding-bottom: 8px;
    }
    .testimonial-card {
      flex: 0 0 320px;
      background: var(--card-bg);
      border-radius: var(--radius);
      padding: 2rem;
      box-shadow: var(--shadow-sm);
      scroll-snap-align: start;
      position: relative;
    }
    .testimonial-card .quote-icon {
      font-size: 2rem;
      color: var(--accent);
      opacity: 0.7;
      margin-bottom: 0.5rem;
    }
    .testimonial-card blockquote {
      font-style: italic;
      color: var(--text-secondary);
      margin-bottom: 1.5rem;
      line-height: 1.6;
    }
    .user-info {
      display: flex;
      align-items: center;
      gap: 0.75rem;
    }
    .avatar {
      width: 42px;
      height: 42px;
      background: #E5ECF0;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--primary);
      font-weight: 600;
    }

    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      border-bottom: 1px solid var(--border-light);
      padding: 1.25rem 0;
    }
    .faq-question {
      width: 100%;
      background: none;
      border: none;
      font-size: 1.1rem;
      font-weight: 600;
      text-align: left;
      display: flex;
      justify-content: space-between;
      align-items: center;
      color: var(--text);
      padding: 0.25rem 0;
    }
    .faq-question i {
      transition: transform 0.3s ease;
      color: var(--primary);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      color: var(--text-secondary);
      padding-right: 20px;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-top: 0.75rem;
    }
    .faq-item.active .faq-question i {
      transform: rotate(180deg);
    }

    .cta-section {
      background: var(--light-section);
      text-align: center;
      border-radius: 0;
    }
    .cta-section h2 {
      margin-bottom: 1rem;
    }
    .cta-section .btn-accent {
      font-size: 1.1rem;
      padding: 16px 40px;
      margin-top: 1.5rem;
    }

    footer {
      background: var(--dark-section);
      color: #CBD5E1;
      padding: 3rem 0 1.5rem;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 2rem;
      margin-bottom: 2rem;
    }
    footer h4 {
      color: white;
      margin-bottom: 1rem;
      font-size: 1rem;
    }
    footer a {
      color: #CBD5E1;
      font-size: 0.9rem;
      display: block;
      margin-bottom: 0.5rem;
    }
    footer a:hover {
      color: var(--accent);
    }
    .copyright {
      text-align: center;
      font-size: 0.8rem;
      color: var(--text-muted);
      border-top: 1px solid rgba(255,255,255,0.1);
      padding-top: 1.5rem;
    }

    @media (max-width: 1024px) {
      .grid-3 { grid-template-columns: repeat(2, 1fr); }
      .stats-grid { grid-template-columns: repeat(2, 1fr); }
      .solution-row, .solution-row.reverse { flex-direction: column; }
    }

    @media (max-width: 768px) {
      .nav-links { display: none; }
      .mobile-menu-btn { display: block; }
      .grid-3 { grid-template-columns: 1fr; }
      .stats-grid { grid-template-columns: repeat(2, 1fr); }
      .footer-grid { grid-template-columns: 1fr 1fr; }
      .hero h1 { font-size: 2rem; }
    }

    .mobile-menu {
      display: none;
      position: fixed;
      top: var(--header-height);
      left: 0;
      width: 100%;
      background: white;
      flex-direction: column;
      padding: 2rem;
      box-shadow: 0 12px 24px rgba(0,0,0,0.08);
      z-index: 999;
    }
    .mobile-menu.open {
      display: flex;
    }
    .mobile-menu a {
      padding: 12px 0;
      font-size: 1.2rem;
      border-bottom: 1px solid #eee;
    }