/* roulang page: index */
:root {
      --primary: #00B365;
      --primary-hover: #009956;
      --primary-light: #E6F8F0;
      --secondary: #00D2A0;
      --accent: #FF6B00;
      --dark-slate: #0B192C;
      --dark-bg: #0F172A;
      --card-dark: #1E293B;
      --text-main: #0F172A;
      --text-body: #334155;
      --text-muted: #64748B;
      --bg-main: #F8FAFC;
      --bg-white: #FFFFFF;
      --border-color: #E2E8F0;
      --shadow-sm: 0 1px 3px rgba(0,0,0,0.05);
      --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.05), 0 2px 4px -1px rgba(0,0,0,0.03);
      --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.08), 0 4px 6px -2px rgba(0,0,0,0.04);
      --radius-sm: 6px;
      --radius-md: 10px;
      --radius-lg: 16px;
      --container-max: 1240px;
    }

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

    html {
      scroll-behavior: smooth;
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
    }

    body {
      background-color: var(--bg-main);
      color: var(--text-body);
      line-height: 1.6;
      font-size: 16px;
      overflow-x: hidden;
    }

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

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

    input, select, textarea, button {
      font-family: inherit;
      font-size: inherit;
    }

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

    .section-title-wrap {
      text-align: center;
      max-width: 800px;
      margin: 0 auto 48px;
    }

    .section-tag {
      display: inline-block;
      color: var(--primary);
      background-color: var(--primary-light);
      padding: 4px 14px;
      border-radius: 20px;
      font-size: 13px;
      font-weight: 600;
      margin-bottom: 12px;
      letter-spacing: 0.5px;
    }

    .section-title {
      font-size: 32px;
      font-weight: 800;
      color: var(--text-main);
      margin-bottom: 16px;
      line-height: 1.3;
    }

    .section-desc {
      font-size: 16px;
      color: var(--text-muted);
      line-height: 1.7;
    }

    /* Top Bar & Header */
    .top-bar {
      background-color: var(--dark-slate);
      color: #94A3B8;
      font-size: 13px;
      padding: 8px 0;
      border-bottom: 1px solid rgba(255,255,255,0.08);
    }
    .top-bar-inner {
      display: flex;
      justify-content: space-between;
      align-items: center;
    }
    .top-bar-left, .top-bar-right {
      display: flex;
      align-items: center;
      gap: 20px;
    }
    .top-bar-item {
      display: flex;
      align-items: center;
      gap: 6px;
    }

    .header-nav {
      background-color: #FFFFFF;
      position: sticky;
      top: 0;
      z-index: 100;
      box-shadow: var(--shadow-sm);
      transition: all 0.3s ease;
    }
    .header-inner {
      display: flex;
      justify-content: space-between;
      align-items: center;
      height: 76px;
    }
    .brand-logo {
      display: flex;
      align-items: center;
      gap: 10px;
      font-size: 22px;
      font-weight: 800;
      color: var(--text-main);
    }
    .logo-badge {
      background: linear-gradient(135deg, var(--primary), var(--secondary));
      color: #fff;
      width: 38px;
      height: 38px;
      display: flex;
      align-items: center;
      justify-content: center;
      border-radius: var(--radius-sm);
      font-size: 18px;
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 28px;
      list-style: none;
    }
    .nav-link {
      color: var(--text-body);
      font-weight: 500;
      font-size: 15px;
      position: relative;
      padding: 6px 0;
    }
    .nav-link:hover, .nav-link.active {
      color: var(--primary);
    }
    .nav-link.active::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 100%;
      height: 2px;
      background-color: var(--primary);
    }
    .header-actions {
      display: flex;
      align-items: center;
      gap: 16px;
    }
    .btn-nav {
      background-color: var(--primary);
      color: #FFFFFF;
      padding: 10px 22px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      font-size: 14px;
      border: none;
      cursor: pointer;
      display: inline-flex;
      align-items: center;
      gap: 6px;
    }
    .btn-nav:hover {
      background-color: var(--primary-hover);
      transform: translateY(-1px);
    }
    .mobile-toggle {
      display: none;
      font-size: 24px;
      color: var(--text-main);
      background: none;
      border: none;
      cursor: pointer;
    }

    /* Hero Section */
    .hero-section {
      position: relative;
      background-color: var(--dark-slate);
      background-image: linear-gradient(rgba(11, 25, 44, 0.88), rgba(11, 25, 44, 0.92)), url('/assets/images/afe99925823c619b.webp');
      background-size: cover;
      background-position: center;
      color: #FFFFFF;
      padding: 70px 0 90px;
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1.15fr 0.85fr;
      gap: 40px;
      align-items: center;
    }
    .hero-content h1 {
      font-size: 38px;
      font-weight: 800;
      line-height: 1.25;
      margin-bottom: 20px;
    }
    .hero-content h1 span {
      color: var(--secondary);
    }
    .hero-desc {
      font-size: 16px;
      color: #CBD5E1;
      margin-bottom: 30px;
      line-height: 1.7;
    }
    .hero-tags-row {
      display: flex;
      flex-wrap: wrap;
      gap: 12px;
      margin-bottom: 32px;
    }
    .hero-pill {
      background: rgba(255,255,255,0.08);
      border: 1px solid rgba(255,255,255,0.15);
      color: #E2E8F0;
      font-size: 13px;
      padding: 6px 14px;
      border-radius: 20px;
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .hero-card-form {
      background: #FFFFFF;
      border-radius: var(--radius-lg);
      padding: 32px;
      color: var(--text-main);
      box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.3);
    }
    .form-head {
      margin-bottom: 20px;
    }
    .form-head h3 {
      font-size: 20px;
      font-weight: 700;
      margin-bottom: 6px;
    }
    .form-head p {
      font-size: 13px;
      color: var(--text-muted);
    }
    .form-group {
      margin-bottom: 16px;
    }
    .form-label {
      display: block;
      font-size: 13px;
      font-weight: 600;
      margin-bottom: 6px;
      color: var(--text-body);
    }
    .form-control {
      width: 100%;
      padding: 10px 14px;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-sm);
      outline: none;
      font-size: 14px;
      transition: border-color 0.2s;
    }
    .form-control:focus {
      border-color: var(--primary);
    }
    .btn-submit {
      width: 100%;
      background-color: var(--primary);
      color: #FFFFFF;
      border: none;
      padding: 12px;
      border-radius: var(--radius-sm);
      font-weight: 700;
      cursor: pointer;
      font-size: 15px;
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
    }
    .btn-submit:hover {
      background-color: var(--primary-hover);
    }

    /* Section Styling */
    .section-padding {
      padding: 80px 0;
    }
    .bg-light-alt {
      background-color: #FFFFFF;
    }

    /* Section 2: Platform Intro */
    .intro-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 50px;
      align-items: center;
    }
    .intro-img-wrap {
      position: relative;
      border-radius: var(--radius-lg);
      overflow: hidden;
      box-shadow: var(--shadow-lg);
    }
    .intro-feature-list {
      display: flex;
      flex-direction: column;
      gap: 18px;
      margin-top: 24px;
    }
    .intro-feature-item {
      display: flex;
      gap: 14px;
      align-items: flex-start;
    }
    .feature-icon-box {
      width: 36px;
      height: 36px;
      background-color: var(--primary-light);
      color: var(--primary);
      border-radius: var(--radius-sm);
      display: flex;
      align-items: center;
      justify-content: center;
      flex-shrink: 0;
      font-size: 16px;
    }

    /* Section 3: Advantages Grid */
    .advantages-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .adv-card {
      background: #FFFFFF;
      padding: 30px;
      border-radius: var(--radius-md);
      border: 1px solid var(--border-color);
      box-shadow: var(--shadow-sm);
      transition: all 0.25s ease;
    }
    .adv-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-lg);
      border-color: var(--primary);
    }
    .adv-icon {
      font-size: 28px;
      color: var(--primary);
      margin-bottom: 18px;
    }
    .adv-title {
      font-size: 18px;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 10px;
    }
    .adv-text {
      font-size: 14px;
      color: var(--text-muted);
      line-height: 1.6;
    }

    /* Section 4: Products Matrix */
    .product-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 30px;
    }
    .prod-card {
      background: #FFFFFF;
      border-radius: var(--radius-lg);
      border: 1px solid var(--border-color);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      display: flex;
      flex-direction: column;
      transition: transform 0.25s ease;
    }
    .prod-card:hover {
      transform: translateY(-5px);
      box-shadow: var(--shadow-lg);
    }
    .prod-header {
      padding: 24px 28px;
      border-bottom: 1px solid var(--border-color);
      background-color: #FAFCFE;
    }
    .prod-tag {
      font-size: 12px;
      color: var(--primary);
      font-weight: 700;
      text-transform: uppercase;
      letter-spacing: 1px;
      margin-bottom: 6px;
    }
    .prod-title {
      font-size: 20px;
      font-weight: 700;
      color: var(--text-main);
    }
    .prod-body {
      padding: 28px;
      flex-grow: 1;
    }
    .prod-desc {
      font-size: 14px;
      color: var(--text-muted);
      margin-bottom: 20px;
      line-height: 1.6;
    }
    .prod-specs {
      list-style: none;
      display: flex;
      flex-direction: column;
      gap: 10px;
      margin-bottom: 24px;
    }
    .prod-specs li {
      font-size: 13px;
      color: var(--text-body);
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .prod-specs li i {
      color: var(--primary);
      font-size: 12px;
    }
    .prod-footer {
      padding: 0 28px 28px;
    }
    .btn-outline {
      display: block;
      text-align: center;
      padding: 10px;
      border: 1px solid var(--primary);
      color: var(--primary);
      border-radius: var(--radius-sm);
      font-weight: 600;
      font-size: 14px;
    }
    .btn-outline:hover {
      background-color: var(--primary);
      color: #FFFFFF;
    }

    /* Section 5: Energy Vision (Dark) */
    .dark-vision-section {
      background-color: var(--dark-bg);
      color: #FFFFFF;
      padding: 80px 0;
    }
    .vision-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 40px;
      align-items: center;
    }
    .vision-card-list {
      display: flex;
      flex-direction: column;
      gap: 20px;
    }
    .vision-card {
      background-color: var(--card-dark);
      padding: 20px 24px;
      border-radius: var(--radius-md);
      border-left: 4px solid var(--secondary);
    }
    .vision-card h4 {
      font-size: 17px;
      margin-bottom: 6px;
      color: #FFFFFF;
    }
    .vision-card p {
      font-size: 14px;
      color: #94A3B8;
      line-height: 1.6;
    }

    /* Section 6: Case Studies */
    .case-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .case-card {
      background: #FFFFFF;
      border-radius: var(--radius-md);
      overflow: hidden;
      border: 1px solid var(--border-color);
      box-shadow: var(--shadow-sm);
    }
    .case-img {
      height: 180px;
      width: 100%;
      object-fit: cover;
    }
    .case-body {
      padding: 22px;
    }
    .case-badge {
      font-size: 12px;
      background-color: var(--primary-light);
      color: var(--primary);
      padding: 3px 8px;
      border-radius: 4px;
      font-weight: 600;
    }
    .case-title {
      font-size: 17px;
      font-weight: 700;
      margin: 10px 0 8px;
      color: var(--text-main);
    }
    .case-text {
      font-size: 13px;
      color: var(--text-muted);
      line-height: 1.6;
    }

    /* Section 7: Metrics Bar */
    .metrics-bar {
      background: linear-gradient(135deg, #0B192C 0%, #1E293B 100%);
      color: #FFFFFF;
      padding: 50px 0;
    }
    .metrics-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
      text-align: center;
    }
    .metric-item {
      padding: 10px;
    }
    .metric-value {
      font-size: 38px;
      font-weight: 800;
      color: var(--secondary);
      line-height: 1.1;
      margin-bottom: 6px;
    }
    .metric-label {
      font-size: 14px;
      color: #CBD5E1;
    }

    /* Section 8: Testimonials */
    .testi-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .testi-card {
      background: #FFFFFF;
      padding: 28px;
      border-radius: var(--radius-md);
      border: 1px solid var(--border-color);
      box-shadow: var(--shadow-sm);
      display: flex;
      flex-direction: column;
      justify-content: space-between;
    }
    .testi-quote {
      font-size: 14px;
      color: var(--text-body);
      line-height: 1.7;
      margin-bottom: 20px;
      position: relative;
    }
    .testi-stars {
      color: #F59E0B;
      font-size: 13px;
      margin-bottom: 12px;
    }
    .testi-user {
      display: flex;
      align-items: center;
      gap: 12px;
      border-top: 1px solid var(--border-color);
      padding-top: 14px;
    }
    .user-avatar-placeholder {
      width: 42px;
      height: 42px;
      background-color: var(--primary-light);
      color: var(--primary);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      font-size: 15px;
    }
    .user-info h5 {
      font-size: 14px;
      font-weight: 700;
      color: var(--text-main);
    }
    .user-info span {
      font-size: 12px;
      color: var(--text-muted);
    }

    /* Section 9: News / Insights */
    .news-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .news-card {
      background: #FFFFFF;
      border-radius: var(--radius-md);
      overflow: hidden;
      border: 1px solid var(--border-color);
      box-shadow: var(--shadow-sm);
    }
    .news-card-body {
      padding: 22px;
    }
    .news-date {
      font-size: 12px;
      color: var(--text-muted);
      margin-bottom: 6px;
    }
    .news-title {
      font-size: 16px;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 10px;
      line-height: 1.4;
    }
    .news-text {
      font-size: 13px;
      color: var(--text-muted);
      line-height: 1.6;
    }

    /* Section 10: FAQ (Accordion) */
    .faq-container {
      max-width: 860px;
      margin: 0 auto;
      display: flex;
      flex-direction: column;
      gap: 14px;
    }
    .faq-item {
      background: #FFFFFF;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      overflow: hidden;
    }
    .faq-item summary {
      padding: 18px 24px;
      font-weight: 700;
      font-size: 16px;
      color: var(--text-main);
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      user-select: none;
      list-style: none;
    }
    .faq-item summary::-webkit-details-marker {
      display: none;
    }
    .faq-item summary::after {
      content: '\f078';
      font-family: 'Font Awesome 6 Free';
      font-weight: 900;
      font-size: 13px;
      color: var(--text-muted);
      transition: transform 0.2s ease;
    }
    .faq-item[open] summary::after {
      transform: rotate(180deg);
      color: var(--primary);
    }
    .faq-content {
      padding: 0 24px 20px;
      font-size: 14px;
      color: var(--text-body);
      line-height: 1.7;
      border-top: 1px solid #F1F5F9;
      margin-top: 8px;
    }

    /* Section 11: Compliance */
    .compliance-section {
      background-color: #FFFFFF;
      border-top: 1px solid var(--border-color);
      border-bottom: 1px solid var(--border-color);
      padding: 40px 0;
    }
    .compliance-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
      align-items: center;
    }
    .compliance-item {
      display: flex;
      align-items: center;
      gap: 14px;
    }
    .compliance-icon {
      font-size: 26px;
      color: var(--primary);
    }
    .compliance-text h5 {
      font-size: 14px;
      font-weight: 700;
      color: var(--text-main);
    }
    .compliance-text p {
      font-size: 12px;
      color: var(--text-muted);
    }

    /* Section 12: CTA Bottom */
    .bottom-cta-section {
      background: linear-gradient(135deg, var(--dark-slate) 0%, #112233 100%);
      color: #FFFFFF;
      padding: 70px 0;
      text-align: center;
    }
    .bottom-cta-inner {
      max-width: 700px;
      margin: 0 auto;
    }
    .bottom-cta-inner h2 {
      font-size: 30px;
      font-weight: 800;
      margin-bottom: 16px;
    }
    .bottom-cta-inner p {
      font-size: 15px;
      color: #CBD5E1;
      margin-bottom: 30px;
    }
    .btn-cta-lg {
      background-color: var(--primary);
      color: #FFFFFF;
      padding: 14px 36px;
      border-radius: var(--radius-sm);
      font-weight: 700;
      font-size: 16px;
      display: inline-flex;
      align-items: center;
      gap: 8px;
    }
    .btn-cta-lg:hover {
      background-color: var(--primary-hover);
      transform: translateY(-2px);
    }

    /* Footer */
    .site-footer {
      background-color: #080E1A;
      color: #94A3B8;
      padding: 60px 0 24px;
      font-size: 14px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 1.5fr 1fr 1fr 1.2fr;
      gap: 40px;
      margin-bottom: 40px;
    }
    .footer-col h4 {
      color: #FFFFFF;
      font-size: 16px;
      font-weight: 700;
      margin-bottom: 18px;
    }
    .footer-links {
      list-style: none;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }
    .footer-links a:hover {
      color: var(--primary);
    }
    .footer-contact-item {
      display: flex;
      align-items: flex-start;
      gap: 10px;
      margin-bottom: 12px;
    }
    .footer-contact-item i {
      color: var(--primary);
      margin-top: 4px;
    }
    .footer-bottom {
      border-top: 1px solid rgba(255,255,255,0.08);
      padding-top: 24px;
      text-align: center;
      font-size: 13px;
      color: #64748B;
    }

    /* Responsive */
    @media (max-width: 1024px) {
      .hero-grid, .intro-grid, .vision-grid {
        grid-template-columns: 1fr;
      }
      .advantages-grid, .product-grid, .case-grid, .news-grid, .testi-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .metrics-grid, .compliance-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .footer-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }

    @media (max-width: 768px) {
      .top-bar {
        display: none;
      }
      .mobile-toggle {
        display: block;
      }
      .nav-links {
        display: none;
        position: absolute;
        top: 76px;
        left: 0;
        width: 100%;
        background-color: #FFFFFF;
        flex-direction: column;
        padding: 20px;
        box-shadow: var(--shadow-lg);
        border-top: 1px solid var(--border-color);
      }
      .nav-links.show {
        display: flex;
      }
      .advantages-grid, .product-grid, .case-grid, .news-grid, .testi-grid {
        grid-template-columns: 1fr;
      }
      .metrics-grid, .compliance-grid, .footer-grid {
        grid-template-columns: 1fr;
      }
      .hero-content h1 {
        font-size: 28px;
      }
      .section-title {
        font-size: 24px;
      }
    }