/* roulang page: index */
:root {
      --primary: #00E599;
      --primary-hover: #00c784;
      --primary-glow: rgba(0, 229, 153, 0.25);
      --bg-dark: #0F1115;
      --bg-dark-card: #161920;
      --bg-dark-border: rgba(255, 255, 255, 0.08);
      --bg-light: #F8F9FA;
      --bg-light-card: #FFFFFF;
      --text-dark-title: #0F1115;
      --text-dark-body: #4A5568;
      --text-dark-muted: #718096;
      --text-light-title: #FFFFFF;
      --text-light-body: #E2E8F0;
      --text-light-muted: #94A3B8;
      --border-light: #E2E8F0;
      --radius-sm: 6px;
      --radius-md: 10px;
      --radius-lg: 16px;
      --shadow-sm: 0 1px 3px rgba(0,0,0,0.05), 0 10px 20px -5px rgba(0,0,0,0.04);
      --shadow-lg: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
      --transition: cubic-bezier(0.16, 1, 0.3, 1) 0.25s;
    }

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

    html {
      scroll-behavior: smooth;
      font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Inter", sans-serif;
      background-color: var(--bg-light);
      color: var(--text-dark-body);
      line-height: 1.6;
    }

    body {
      overflow-x: hidden;
    }

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

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

    .container {
      width: 100%;
      max-width: 1240px;
      margin: 0 auto;
      padding: 0 24px;
    }

    /* Top Notice Bar */
    .top-bar {
      background-color: #08090C;
      color: var(--text-light-muted);
      font-size: 13px;
      padding: 8px 0;
      border-bottom: 1px solid rgba(255, 255, 255, 0.05);
    }
    .top-bar-content {
      display: flex;
      justify-content: space-between;
      align-items: center;
    }
    .status-indicator {
      display: inline-flex;
      align-items: center;
      gap: 6px;
    }
    .status-dot {
      width: 8px;
      height: 8px;
      background: var(--primary);
      border-radius: 50%;
      box-shadow: 0 0 8px var(--primary);
    }

    /* Header Nav */
    .header {
      position: sticky;
      top: 0;
      z-index: 1000;
      background: rgba(15, 17, 21, 0.92);
      backdrop-filter: blur(12px);
      border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
    }
    .brand-logo {
      font-size: 22px;
      font-weight: 800;
      color: #FFFFFF;
      display: flex;
      align-items: center;
      gap: 10px;
      letter-spacing: -0.5px;
    }
    .brand-logo span {
      color: var(--primary);
    }
    .nav-menu {
      display: flex;
      align-items: center;
      gap: 28px;
      list-style: none;
    }
    .nav-link {
      color: var(--text-light-body);
      font-size: 15px;
      font-weight: 500;
      transition: color var(--transition);
    }
    .nav-link:hover, .nav-link.active {
      color: var(--primary);
    }
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 12px 24px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      font-size: 15px;
      cursor: pointer;
      border: 1px solid transparent;
      transition: all var(--transition);
    }
    .btn-primary {
      background-color: var(--primary);
      color: #0F1115;
    }
    .btn-primary:hover {
      background-color: var(--primary-hover);
      transform: translateY(-2px);
      box-shadow: 0 4px 16px var(--primary-glow);
    }
    .btn-outline {
      background-color: transparent;
      border-color: rgba(255, 255, 255, 0.2);
      color: #FFFFFF;
    }
    .btn-outline:hover {
      border-color: var(--primary);
      color: var(--primary);
      background-color: rgba(0, 229, 153, 0.05);
    }
    .mobile-menu-btn {
      display: none;
      background: none;
      border: none;
      color: #FFF;
      font-size: 24px;
      cursor: pointer;
    }

    /* Section Global */
    section {
      padding: 96px 0;
      position: relative;
    }
    .section-dark {
      background-color: var(--bg-dark);
      color: var(--text-light-body);
    }
    .section-light {
      background-color: var(--bg-light);
      color: var(--text-dark-body);
    }
    .section-alt {
      background-color: #FFFFFF;
    }
    .section-header {
      margin-bottom: 56px;
      max-width: 780px;
    }
    .section-header.center {
      text-align: center;
      margin-left: auto;
      margin-right: auto;
    }
    .section-tag {
      display: inline-block;
      font-size: 13px;
      font-weight: 700;
      color: var(--primary);
      text-transform: uppercase;
      letter-spacing: 1.5px;
      margin-bottom: 12px;
      background: rgba(0, 229, 153, 0.1);
      padding: 4px 12px;
      border-radius: 4px;
    }
    .section-title {
      font-size: 34px;
      font-weight: 800;
      line-height: 1.25;
      margin-bottom: 16px;
    }
    .section-dark .section-title {
      color: var(--text-light-title);
    }
    .section-light .section-title, .section-alt .section-title {
      color: var(--text-dark-title);
    }
    .section-desc {
      font-size: 16px;
      line-height: 1.7;
    }
    .section-dark .section-desc {
      color: var(--text-light-muted);
    }
    .section-light .section-desc, .section-alt .section-desc {
      color: var(--text-dark-muted);
    }

    /* 01 Hero Section */
    .hero-section {
      background: linear-gradient(180deg, rgba(15, 17, 21, 0.85) 0%, rgba(15, 17, 21, 0.95) 100%), url('/assets/images/02d8dfbc6143d26a.png') center/cover no-repeat;
      padding: 120px 0 100px;
      border-bottom: 1px solid var(--bg-dark-border);
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1.15fr 0.85fr;
      gap: 48px;
      align-items: center;
    }
    .hero-h1 {
      font-size: 48px;
      font-weight: 900;
      line-height: 1.15;
      color: #FFFFFF;
      margin-bottom: 24px;
      letter-spacing: -1px;
    }
    .hero-h1 span {
      color: var(--primary);
    }
    .hero-p {
      font-size: 16px;
      line-height: 1.75;
      color: var(--text-light-body);
      margin-bottom: 36px;
    }
    .hero-actions {
      display: flex;
      gap: 16px;
      margin-bottom: 48px;
    }
    .hero-kpi-bar {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 20px;
      border-top: 1px solid rgba(255, 255, 255, 0.1);
      padding-top: 24px;
    }
    .kpi-item h4 {
      font-size: 26px;
      color: var(--primary);
      font-weight: 800;
      margin-bottom: 4px;
    }
    .kpi-item p {
      font-size: 13px;
      color: var(--text-light-muted);
    }
    .hero-visual {
      position: relative;
    }
    .hero-card-preview {
      background: var(--bg-dark-card);
      border: 1px solid var(--bg-dark-border);
      border-radius: var(--radius-lg);
      padding: 16px;
      box-shadow: var(--shadow-lg);
    }
    .hero-card-preview img {
      border-radius: var(--radius-md);
      margin-bottom: 16px;
    }
    .hero-status-pill {
      display: flex;
      justify-content: space-between;
      align-items: center;
      background: rgba(255, 255, 255, 0.03);
      padding: 10px 16px;
      border-radius: var(--radius-sm);
      font-size: 13px;
      color: var(--text-light-muted);
    }
    .live-tag {
      background: #EF4444;
      color: #FFF;
      padding: 2px 8px;
      border-radius: 4px;
      font-weight: 700;
      font-size: 11px;
    }

    /* 02 Engine Intro */
    .engine-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 60px;
      align-items: center;
    }
    .engine-img-box {
      border-radius: var(--radius-lg);
      overflow: hidden;
      border: 1px solid var(--border-light);
      box-shadow: var(--shadow-sm);
    }
    .protocol-list {
      margin-top: 28px;
      display: grid;
      gap: 16px;
    }
    .protocol-card {
      display: flex;
      gap: 16px;
      background: #FFFFFF;
      padding: 18px 20px;
      border-radius: var(--radius-md);
      border: 1px solid var(--border-light);
    }
    .protocol-card h4 {
      font-size: 16px;
      color: var(--text-dark-title);
      margin-bottom: 4px;
    }
    .protocol-card p {
      font-size: 14px;
      color: var(--text-dark-muted);
    }

    /* 03 Core Capabilities */
    .grid-3x2 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .cap-card {
      background: #FFFFFF;
      padding: 32px 28px;
      border-radius: var(--radius-md);
      border: 1px solid var(--border-light);
      transition: transform var(--transition), box-shadow var(--transition);
    }
    .cap-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-lg);
      border-color: rgba(0, 229, 153, 0.4);
    }
    .cap-badge {
      width: 44px;
      height: 44px;
      background: rgba(0, 229, 153, 0.1);
      color: #00A86B;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 800;
      border-radius: 8px;
      margin-bottom: 20px;
      font-size: 18px;
    }
    .cap-card h3 {
      font-size: 19px;
      font-weight: 700;
      color: var(--text-dark-title);
      margin-bottom: 12px;
    }
    .cap-card p {
      font-size: 14px;
      line-height: 1.65;
      color: var(--text-dark-muted);
    }

    /* 04 Hot Products Matrix */
    .matrix-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .matrix-card {
      background: var(--bg-dark-card);
      border: 1px solid var(--bg-dark-border);
      border-radius: var(--radius-lg);
      padding: 36px 28px;
      display: flex;
      flex-direction: column;
      justify-content: space-between;
      position: relative;
    }
    .matrix-card.featured {
      border-color: var(--primary);
      box-shadow: 0 0 25px var(--primary-glow);
    }
    .featured-badge {
      position: absolute;
      top: -12px;
      right: 24px;
      background: var(--primary);
      color: #0F1115;
      font-size: 12px;
      font-weight: 700;
      padding: 4px 12px;
      border-radius: 20px;
    }
    .matrix-card h3 {
      font-size: 22px;
      color: #FFF;
      margin-bottom: 12px;
    }
    .matrix-card .matrix-desc {
      font-size: 14px;
      color: var(--text-light-muted);
      margin-bottom: 24px;
      line-height: 1.6;
    }
    .matrix-features {
      list-style: none;
      margin-bottom: 32px;
      display: grid;
      gap: 12px;
    }
    .matrix-features li {
      font-size: 14px;
      color: var(--text-light-body);
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .matrix-features li::before {
      content: "✓";
      color: var(--primary);
      font-weight: bold;
    }

    /* 05 Dark Mode Philosophy & Distributed Case */
    .dist-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 48px;
      align-items: center;
    }
    .dist-content h3 {
      font-size: 26px;
      color: #FFF;
      margin-bottom: 16px;
    }
    .dist-content p {
      font-size: 15px;
      color: var(--text-light-muted);
      margin-bottom: 24px;
      line-height: 1.7;
    }
    .dist-stats {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 20px;
      margin-top: 24px;
    }
    .dist-stat-box {
      background: rgba(255, 255, 255, 0.03);
      padding: 16px;
      border-radius: var(--radius-sm);
      border: 1px solid var(--bg-dark-border);
    }
    .dist-stat-box .num {
      font-size: 22px;
      color: var(--primary);
      font-weight: 700;
    }
    .dist-stat-box .label {
      font-size: 13px;
      color: var(--text-light-muted);
      margin-top: 4px;
    }

    /* 06 User Stories */
    .story-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .story-card {
      background: #FFFFFF;
      border-radius: var(--radius-md);
      overflow: hidden;
      border: 1px solid var(--border-light);
      display: flex;
      flex-direction: column;
    }
    .story-card img {
      width: 100%;
      height: 200px;
      object-fit: cover;
    }
    .story-body {
      padding: 24px;
      flex-grow: 1;
    }
    .story-tag {
      font-size: 12px;
      color: #00A86B;
      font-weight: 700;
      margin-bottom: 8px;
      display: inline-block;
    }
    .story-body h3 {
      font-size: 18px;
      color: var(--text-dark-title);
      margin-bottom: 12px;
      line-height: 1.4;
    }
    .story-body p {
      font-size: 14px;
      color: var(--text-dark-muted);
      line-height: 1.6;
    }

    /* 07 Metric Data Bar */
    .metric-section {
      background: #08090C;
      padding: 60px 0;
      border-top: 1px solid var(--bg-dark-border);
      border-bottom: 1px solid var(--bg-dark-border);
    }
    .metric-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
      text-align: center;
    }
    .metric-box h3 {
      font-size: 40px;
      font-weight: 900;
      color: var(--primary);
      margin-bottom: 6px;
      letter-spacing: -1px;
    }
    .metric-box p {
      font-size: 14px;
      color: var(--text-light-muted);
      line-height: 1.5;
    }

    /* 08 Social Proof */
    .proof-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .proof-card {
      background: #FFFFFF;
      padding: 32px 28px;
      border-radius: var(--radius-md);
      border: 1px solid var(--border-light);
    }
    .proof-rating {
      color: #F59E0B;
      font-size: 16px;
      margin-bottom: 16px;
    }
    .proof-quote {
      font-size: 15px;
      color: var(--text-dark-body);
      line-height: 1.7;
      margin-bottom: 24px;
    }
    .proof-author {
      display: flex;
      align-items: center;
      gap: 12px;
    }
    .proof-avatar {
      width: 44px;
      height: 44px;
      border-radius: 50%;
      background: #E2E8F0;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      color: var(--text-dark-title);
    }
    .proof-info h4 {
      font-size: 15px;
      color: var(--text-dark-title);
    }
    .proof-info p {
      font-size: 13px;
      color: var(--text-dark-muted);
    }

    /* 09 News & Trends */
    .news-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .news-card {
      background: #FFFFFF;
      border-radius: var(--radius-md);
      padding: 24px;
      border: 1px solid var(--border-light);
    }
    .news-date {
      font-size: 12px;
      color: var(--text-dark-muted);
      margin-bottom: 10px;
    }
    .news-card h3 {
      font-size: 17px;
      color: var(--text-dark-title);
      margin-bottom: 12px;
      line-height: 1.45;
    }
    .news-card p {
      font-size: 14px;
      color: var(--text-dark-muted);
      line-height: 1.6;
      margin-bottom: 16px;
    }
    .news-link {
      font-size: 14px;
      color: #00A86B;
      font-weight: 600;
      display: inline-flex;
      align-items: center;
      gap: 4px;
    }

    /* 10 Interactive FAQ */
    .faq-container {
      max-width: 840px;
      margin: 0 auto;
    }
    .faq-item {
      background: var(--bg-dark-card);
      border: 1px solid var(--bg-dark-border);
      border-radius: var(--radius-md);
      margin-bottom: 16px;
      overflow: hidden;
    }
    .faq-question {
      padding: 22px 24px;
      font-size: 16px;
      font-weight: 600;
      color: #FFFFFF;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      user-select: none;
    }
    .faq-icon {
      font-size: 18px;
      transition: transform var(--transition);
      color: var(--primary);
    }
    .faq-answer {
      padding: 0 24px 22px;
      font-size: 14px;
      color: var(--text-light-muted);
      line-height: 1.7;
      display: none;
    }
    .faq-item.active .faq-answer {
      display: block;
    }
    .faq-item.active .faq-icon {
      transform: rotate(45deg);
    }

    /* 11 Guarantee Bar */
    .guarantee-bar {
      background: #FFFFFF;
      padding: 48px 0;
      border-top: 1px solid var(--border-light);
      border-bottom: 1px solid var(--border-light);
    }
    .guarantee-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
    }
    .guarantee-item {
      display: flex;
      align-items: center;
      gap: 16px;
    }
    .guarantee-icon {
      width: 44px;
      height: 44px;
      border-radius: 8px;
      background: rgba(0, 229, 153, 0.1);
      color: #00A86B;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 20px;
      font-weight: 800;
      flex-shrink: 0;
    }
    .guarantee-text h4 {
      font-size: 15px;
      color: var(--text-dark-title);
      margin-bottom: 2px;
    }
    .guarantee-text p {
      font-size: 13px;
      color: var(--text-dark-muted);
    }

    /* 12 Bottom CTA Form */
    .bottom-cta-section {
      background: linear-gradient(180deg, #0F1115 0%, #050608 100%);
      padding: 100px 0;
    }
    .cta-card-box {
      background: var(--bg-dark-card);
      border: 1px solid var(--bg-dark-border);
      border-radius: var(--radius-lg);
      padding: 56px;
      display: grid;
      grid-template-columns: 1fr 1.1fr;
      gap: 48px;
    }
    .cta-info h2 {
      font-size: 32px;
      color: #FFFFFF;
      font-weight: 800;
      margin-bottom: 16px;
      line-height: 1.3;
    }
    .cta-info p {
      font-size: 15px;
      color: var(--text-light-muted);
      line-height: 1.7;
      margin-bottom: 32px;
    }
    .cta-contact-meta {
      display: grid;
      gap: 12px;
      font-size: 14px;
      color: var(--text-light-body);
    }
    .form-group {
      margin-bottom: 18px;
    }
    .form-label {
      display: block;
      font-size: 13px;
      color: var(--text-light-muted);
      margin-bottom: 6px;
      font-weight: 500;
    }
    .form-input, .form-select {
      width: 100%;
      padding: 12px 16px;
      background: rgba(255, 255, 255, 0.05);
      border: 1px solid rgba(255, 255, 255, 0.15);
      border-radius: var(--radius-sm);
      color: #FFFFFF;
      font-size: 14px;
      outline: none;
      transition: border-color var(--transition);
    }
    .form-input:focus, .form-select:focus {
      border-color: var(--primary);
      background: rgba(255, 255, 255, 0.08);
    }
    .form-select option {
      background: var(--bg-dark-card);
      color: #FFFFFF;
    }
    .form-submit-btn {
      width: 100%;
      padding: 14px;
      background: var(--primary);
      color: #0F1115;
      font-weight: 700;
      border: none;
      border-radius: var(--radius-sm);
      font-size: 15px;
      cursor: pointer;
      transition: all var(--transition);
      margin-top: 8px;
    }
    .form-submit-btn:hover {
      background: var(--primary-hover);
      box-shadow: 0 4px 16px var(--primary-glow);
    }

    /* Footer */
    .footer {
      background: #08090C;
      color: var(--text-light-muted);
      padding: 60px 0 32px;
      border-top: 1px solid rgba(255, 255, 255, 0.05);
      font-size: 13px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1.5fr;
      gap: 40px;
      margin-bottom: 48px;
    }
    .footer-brand h3 {
      font-size: 20px;
      color: #FFF;
      margin-bottom: 12px;
      font-weight: 800;
    }
    .footer-brand p {
      line-height: 1.7;
      max-width: 320px;
    }
    .footer-col h4 {
      color: #FFF;
      font-size: 15px;
      margin-bottom: 16px;
      font-weight: 600;
    }
    .footer-col ul {
      list-style: none;
      display: grid;
      gap: 10px;
    }
    .footer-col a:hover {
      color: var(--primary);
    }
    .footer-bottom {
      border-top: 1px solid rgba(255, 255, 255, 0.06);
      padding-top: 24px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      flex-wrap: wrap;
      gap: 12px;
    }

    /* Responsive */
    @media (max-width: 1024px) {
      .hero-grid, .engine-grid, .dist-grid, .cta-card-box {
        grid-template-columns: 1fr;
        gap: 40px;
      }
      .grid-3x2, .matrix-grid, .story-grid, .proof-grid, .news-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .metric-grid, .guarantee-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 32px;
      }
      .footer-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }

    @media (max-width: 768px) {
      .top-bar {
        display: none;
      }
      .nav-menu {
        display: none;
      }
      .mobile-menu-btn {
        display: block;
      }
      .grid-3x2, .matrix-grid, .story-grid, .proof-grid, .news-grid, .metric-grid, .guarantee-grid {
        grid-template-columns: 1fr;
      }
      .hero-h1 {
        font-size: 34px;
      }
      .hero-kpi-bar {
        grid-template-columns: 1fr;
        gap: 16px;
      }
      .cta-card-box {
        padding: 32px 20px;
      }
      .footer-grid {
        grid-template-columns: 1fr;
      }
      .hero-actions {
        flex-direction: column;
      }
    }