/* roulang page: index */
:root {
      --primary: #F15A24;
      --primary-dark: #D94A1A;
      --secondary: #1E1E2F;
      --accent: #F5A623;
      --bg: #F7F5F2;
      --card: #FFFFFF;
      --text-heading: #1E1E2F;
      --text-body: #4A4A5A;
      --text-muted: #9B9B9B;
      --radius: 16px;
      --shadow-sm: 0 4px 20px rgba(0,0,0,0.04);
      --shadow-md: 0 8px 30px rgba(0,0,0,0.08);
      --transition: all 0.3s ease;
    }
    * {
      box-sizing: border-box;
    }
    body {
      font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial, sans-serif;
      background: var(--bg);
      color: var(--text-body);
      line-height: 1.7;
      margin: 0;
      -webkit-font-smoothing: antialiased;
      scroll-behavior: smooth;
    }
    img {
      max-width: 100%;
      display: block;
      height: auto;
    }
    a {
      text-decoration: none;
      color: inherit;
    }
    button, .button {
      cursor: pointer;
      font-family: inherit;
    }
    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }
    .section-padding {
      padding: 100px 0;
    }
    @media (max-width: 1024px) {
      .section-padding {
        padding: 80px 0;
      }
    }
    @media (max-width: 640px) {
      .section-padding {
        padding: 60px 0;
      }
      .container {
        padding: 0 16px;
      }
    }

    /* Header */
    .site-header {
      position: sticky;
      top: 0;
      z-index: 40;
      background: #fff;
      height: 72px;
      box-shadow: 0 1px 0 rgba(0,0,0,0.05);
      transition: var(--transition);
    }
    .site-header.scrolled {
      box-shadow: 0 2px 12px rgba(0,0,0,0.04);
    }
    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
    }
    .logo {
      font-size: 24px;
      font-weight: 700;
      color: var(--primary);
      letter-spacing: 1px;
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .logo i {
      font-size: 28px;
      color: var(--accent);
    }
    .nav-links {
      display: flex;
      gap: 32px;
      font-weight: 500;
      color: var(--text-body);
    }
    .nav-links a {
      position: relative;
      padding: 8px 0;
      font-size: 16px;
      transition: color 0.2s;
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: var(--primary);
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 3px;
      background: var(--primary);
      transition: width 0.25s ease;
      border-radius: 3px;
    }
    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 100%;
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 6px;
      background: transparent;
      border: none;
      padding: 8px;
    }
    .hamburger span {
      display: block;
      width: 26px;
      height: 3px;
      background: var(--secondary);
      border-radius: 3px;
      transition: var(--transition);
    }
    @media (max-width: 1024px) {
      .nav-links {
        display: none;
        position: fixed;
        top: 72px;
        left: 0;
        width: 100%;
        background: var(--secondary);
        flex-direction: column;
        padding: 32px 24px;
        gap: 24px;
        z-index: 50;
        box-shadow: 0 10px 20px rgba(0,0,0,0.2);
      }
      .nav-links.open {
        display: flex;
      }
      .nav-links a {
        color: #fff;
        font-size: 20px;
        border-bottom: 1px solid rgba(255,255,255,0.2);
        padding-bottom: 12px;
      }
      .nav-links a::after {
        display: none;
      }
      .hamburger {
        display: flex;
      }
    }

    /* Hero */
    .hero {
      background: linear-gradient(135deg, #F15A24 0%, #F5A623 100%);
      position: relative;
      overflow: hidden;
      color: #fff;
      padding: 80px 0;
      min-height: 600px;
      display: flex;
      align-items: center;
    }
    .hero::before {
      content: '';
      position: absolute;
      inset: 0;
      background-image: radial-gradient(circle at 30% 40%, rgba(255,255,255,0.08) 0%, transparent 50%);
      pointer-events: none;
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 48px;
      align-items: center;
    }
    .hero-content h1 {
      font-size: 42px;
      line-height: 1.25;
      font-weight: 700;
      letter-spacing: -0.5px;
      margin-bottom: 24px;
      color: #fff;
    }
    .hero-content h1 span {
      color: var(--accent);
    }
    .hero-content p {
      font-size: 18px;
      opacity: 0.9;
      max-width: 500px;
      margin-bottom: 32px;
    }
    .btn-group {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: #fff;
      color: var(--primary);
      font-weight: 600;
      padding: 14px 36px;
      border-radius: 30px;
      border: none;
      font-size: 16px;
      transition: var(--transition);
      display: inline-flex;
      align-items: center;
      gap: 8px;
      box-shadow: 0 8px 20px rgba(0,0,0,0.1);
    }
    .btn-primary:hover {
      background: #f2f2f2;
      box-shadow: 0 12px 28px rgba(0,0,0,0.2);
      transform: translateY(-2px);
      color: var(--primary-dark);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid rgba(255,255,255,0.9);
      color: #fff;
      font-weight: 600;
      padding: 14px 36px;
      border-radius: 30px;
      font-size: 16px;
      transition: var(--transition);
    }
    .btn-outline:hover {
      background: rgba(255,255,255,0.15);
      border-color: #fff;
    }
    .hero-visual {
      display: flex;
      justify-content: center;
      align-items: center;
    }
    .hero-visual img {
      border-radius: 24px;
      box-shadow: 0 20px 40px rgba(0,0,0,0.3);
      max-width: 100%;
    }
    @media (max-width: 1024px) {
      .hero-grid {
        grid-template-columns: 1fr;
        text-align: center;
      }
      .hero-content p {
        margin-left: auto;
        margin-right: auto;
      }
      .btn-group {
        justify-content: center;
      }
      .hero-visual img {
        max-height: 350px;
        object-fit: cover;
      }
    }
    @media (max-width: 640px) {
      .hero-content h1 {
        font-size: 32px;
      }
    }

    /* Section titles */
    .section-title h2 {
      font-size: 32px;
      font-weight: 700;
      color: var(--text-heading);
      margin-bottom: 16px;
    }
    .section-title .subtitle {
      color: var(--text-muted);
      font-size: 18px;
      margin-bottom: 48px;
    }

    /* Advantages */
    .adv-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 32px;
    }
    .adv-card {
      background: var(--card);
      border-radius: var(--radius);
      padding: 40px 32px;
      box-shadow: var(--shadow-sm);
      text-align: center;
      transition: var(--transition);
    }
    .adv-card:hover {
      box-shadow: var(--shadow-md);
      transform: translateY(-4px);
    }
    .adv-icon {
      font-size: 48px;
      color: var(--primary);
      margin-bottom: 20px;
    }
    .adv-number {
      font-size: 48px;
      font-weight: 800;
      color: var(--accent);
      line-height: 1.2;
    }
    .adv-card h3 {
      font-size: 22px;
      font-weight: 600;
      margin: 16px 0 12px;
    }
    @media (max-width: 1024px) {
      .adv-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }
    @media (max-width: 640px) {
      .adv-grid {
        grid-template-columns: 1fr;
      }
    }

    /* Services */
    .service-card {
      display: grid;
      grid-template-columns: 1fr 1fr;
      background: var(--card);
      border-radius: var(--radius);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      margin-bottom: 40px;
    }
    .service-img img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      min-height: 300px;
    }
    .service-body {
      padding: 40px;
      display: flex;
      flex-direction: column;
      justify-content: center;
    }
    .service-body h3 {
      font-size: 26px;
      font-weight: 700;
      margin-bottom: 16px;
    }
    .service-link {
      color: var(--primary);
      font-weight: 600;
      display: inline-flex;
      align-items: center;
      gap: 6px;
      margin-top: 16px;
      transition: gap 0.2s;
    }
    .service-link:hover {
      gap: 12px;
    }
    @media (max-width: 768px) {
      .service-card {
        grid-template-columns: 1fr;
      }
    }

    /* Cases */
    .stats-row {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 32px;
      margin-bottom: 60px;
    }
    .stat-item {
      text-align: center;
    }
    .stat-number {
      font-size: 48px;
      font-weight: 800;
      color: var(--accent);
      line-height: 1.2;
    }
    .case-cards {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 32px;
    }
    .case-card {
      background: var(--card);
      border-radius: var(--radius);
      padding: 32px;
      box-shadow: var(--shadow-sm);
      display: flex;
      gap: 24px;
      align-items: center;
    }
    .case-card img {
      width: 120px;
      height: 120px;
      object-fit: cover;
      border-radius: 12px;
    }
    @media (max-width: 768px) {
      .stats-row {
        grid-template-columns: repeat(2, 1fr);
      }
      .case-cards {
        grid-template-columns: 1fr;
      }
    }

    /* Solutions */
    .steps {
      display: flex;
      justify-content: space-between;
      align-items: flex-start;
      gap: 24px;
      flex-wrap: wrap;
    }
    .step {
      flex: 1;
      text-align: center;
      position: relative;
    }
    .step-circle {
      width: 64px;
      height: 64px;
      background: var(--primary);
      color: #fff;
      font-weight: 700;
      font-size: 24px;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      margin: 0 auto 20px;
    }
    .step h3 {
      font-weight: 700;
    }
    @media (max-width: 640px) {
      .steps {
        flex-direction: column;
      }
    }

    /* FAQ */
    .accordion-item {
      background: var(--bg);
      border-radius: 12px;
      margin-bottom: 12px;
      box-shadow: 0 2px 8px rgba(0,0,0,0.02);
      border-left: 4px solid transparent;
      transition: var(--transition);
    }
    .accordion-item.is-active {
      border-left-color: var(--primary);
      background: #fff;
    }
    .accordion-title {
      font-size: 18px;
      font-weight: 600;
      padding: 20px 24px;
      color: var(--text-heading);
      cursor: pointer;
      display: flex;
      justify-content: space-between;
    }
    .accordion-content {
      padding: 0 24px 20px;
      color: var(--text-body);
    }

    /* CTA */
    .cta-section {
      background: linear-gradient(135deg, #F15A24 0%, #F5A623 100%);
      text-align: center;
      color: #fff;
    }
    .cta-section h2 {
      color: #fff;
      font-size: 36px;
    }

    /* Footer */
    .footer {
      background: var(--secondary);
      color: #ccc;
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }
    .footer a {
      color: #ddd;
      opacity: 0.8;
    }
    .footer a:hover {
      opacity: 1;
      color: #fff;
    }
    .copyright {
      text-align: center;
      margin-top: 40px;
      border-top: 1px solid rgba(255,255,255,0.1);
      padding-top: 24px;
      font-size: 14px;
    }
    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
    }
    @media (max-width: 480px) {
      .footer-grid {
        grid-template-columns: 1fr;
      }
    }