/* roulang page: index */
:root {
      --primary-color: #1B4F93;
      --primary-hover: #143D73;
      --accent-color: #DDA83B;
      --accent-hover: #C5932D;
      --bg-page: #F8FAFC;
      --bg-card: #FFFFFF;
      --bg-dark: #0F1E36;
      --bg-header: #0A111F;
      --bg-footer: #080C14;
      --text-main: #0F172A;
      --text-body: #334155;
      --text-muted: #64748B;
      --border-color: #E2E8F0;
      --radius-sm: 4px;
      --radius-md: 8px;
      --radius-lg: 14px;
      --shadow-sm: 0 4px 20px rgba(15, 23, 42, 0.06);
      --shadow-hover: 0 12px 28px rgba(27, 79, 147, 0.12);
      --transition: all 0.28s ease-in-out;
    }

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

    body {
      font-family: system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif;
      background-color: var(--bg-page);
      color: var(--text-body);
      line-height: 1.65;
      -webkit-font-smoothing: antialiased;
    }

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

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

    .section-wrap {
      padding: 80px 0;
      position: relative;
    }

    .section-wrap.alt-bg {
      background-color: #FFFFFF;
      border-top: 1px solid var(--border-color);
      border-bottom: 1px solid var(--border-color);
    }

    .section-header {
      margin-bottom: 50px;
    }

    .section-header .section-tag {
      display: inline-block;
      font-size: 13px;
      font-weight: 700;
      color: var(--primary-color);
      background-color: rgba(27, 79, 147, 0.08);
      padding: 4px 14px;
      border-radius: 20px;
      margin-bottom: 12px;
      letter-spacing: 0.5px;
    }

    .section-header h2 {
      font-size: 32px;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 16px;
      line-height: 1.3;
    }

    .section-header p {
      font-size: 16px;
      color: var(--text-muted);
      max-width: 780px;
      margin: 0 auto;
    }

    .btn-gold {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      background-color: var(--accent-color);
      color: #0F172A;
      font-weight: 600;
      padding: 12px 28px;
      border-radius: var(--radius-sm);
      transition: var(--transition);
      border: 1px solid var(--accent-color);
      cursor: pointer;
    }
    .btn-gold:hover {
      background-color: var(--accent-hover);
      color: #0F172A;
      box-shadow: 0 4px 14px rgba(221, 168, 59, 0.35);
    }

    .btn-primary {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      background-color: var(--primary-color);
      color: #FFFFFF;
      font-weight: 600;
      padding: 12px 28px;
      border-radius: var(--radius-sm);
      transition: var(--transition);
      border: 1px solid var(--primary-color);
      cursor: pointer;
    }
    .btn-primary:hover {
      background-color: var(--primary-hover);
      color: #FFFFFF;
      box-shadow: 0 4px 16px rgba(27, 79, 147, 0.3);
    }

    .btn-outline {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      background-color: transparent;
      color: #FFFFFF;
      font-weight: 600;
      padding: 12px 26px;
      border-radius: var(--radius-sm);
      border: 1px solid rgba(255, 255, 255, 0.4);
      transition: var(--transition);
      cursor: pointer;
    }
    .btn-outline:hover {
      background-color: rgba(255, 255, 255, 0.1);
      border-color: #FFFFFF;
      color: #FFFFFF;
    }

    /* Header Nav */
    .site-header {
      background-color: var(--bg-header);
      position: sticky;
      top: 0;
      z-index: 999;
      box-shadow: 0 2px 10px rgba(0,0,0,0.3);
    }
    .top-bar-sub {
      background-color: #060B14;
      font-size: 12px;
      color: #94A3B8;
      padding: 6px 0;
      border-bottom: 1px solid rgba(255, 255, 255, 0.06);
    }
    .main-nav-bar {
      padding: 14px 0;
    }
    .nav-brand {
      font-size: 20px;
      font-weight: 700;
      color: #FFFFFF;
      display: flex;
      align-items: center;
      gap: 10px;
    }
    .nav-brand-icon {
      width: 28px;
      height: 28px;
      background: linear-gradient(135deg, var(--accent-color), var(--primary-color));
      border-radius: 6px;
      display: inline-block;
    }
    .nav-links {
      display: flex;
      list-style: none;
      gap: 22px;
      margin: 0;
      align-items: center;
    }
    .nav-links li a {
      color: #CBD5E1;
      font-size: 15px;
      font-weight: 500;
    }
    .nav-links li a:hover {
      color: #FFFFFF;
    }

    /* Section 1: Hero Orbit Banner */
    #hero {
      background: radial-gradient(circle at 80% 20%, #17325C 0%, #0A111F 70%), url('/assets/images/d5d93805d70e291a.webp') center/cover no-repeat;
      padding: 90px 0 100px;
      color: #FFFFFF;
      position: relative;
      overflow: hidden;
    }
    #hero::before {
      content: "";
      position: absolute;
      top: 0; left: 0; right: 0; bottom: 0;
      background: rgba(10, 17, 31, 0.85);
      z-index: 1;
    }
    #hero .grid-container {
      position: relative;
      z-index: 2;
    }
    .hero-h1 {
      font-size: 42px;
      font-weight: 800;
      line-height: 1.25;
      color: #FFFFFF;
      margin-bottom: 20px;
    }
    .hero-h1 span {
      color: var(--accent-color);
    }
    .hero-intro {
      font-size: 16px;
      line-height: 1.8;
      color: #CBD5E1;
      margin-bottom: 30px;
      max-width: 620px;
    }
    .hero-actions {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .faux-rank-board {
      background: rgba(15, 30, 54, 0.8);
      border: 1px solid rgba(255, 255, 255, 0.12);
      border-radius: var(--radius-md);
      padding: 24px;
      backdrop-filter: blur(10px);
      box-shadow: 0 10px 30px rgba(0,0,0,0.4);
    }
    .board-head {
      border-bottom: 1px solid rgba(255, 255, 255, 0.1);
      padding-bottom: 12px;
      margin-bottom: 16px;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }
    .board-head h3 {
      font-size: 16px;
      font-weight: 600;
      color: #FFFFFF;
      margin: 0;
    }
    .board-item {
      display: flex;
      justify-content: space-between;
      align-items: center;
      padding: 10px 0;
      border-bottom: 1px solid rgba(255, 255, 255, 0.05);
      font-size: 14px;
    }
    .board-item:last-child {
      border-bottom: none;
    }
    .board-badge {
      font-size: 11px;
      padding: 2px 8px;
      border-radius: 4px;
      background: rgba(221, 168, 59, 0.2);
      color: var(--accent-color);
      font-weight: 600;
    }

    /* Section 2: Platform Overview */
    .overview-img-box {
      border-radius: var(--radius-md);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      border: 1px solid var(--border-color);
    }
    .tech-specs-box {
      background-color: #EDF4FB;
      border-left: 4px solid var(--primary-color);
      padding: 18px 22px;
      margin: 22px 0;
      border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
      font-size: 14px;
      color: #1E3A8A;
      font-family: monospace, system-ui;
    }

    /* Section 3: Core Advantages */
    .feature-card {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 32px 24px;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      height: 100%;
    }
    .feature-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
      border-color: #CBD5E1;
    }
    .feature-card-icon {
      width: 48px;
      height: 48px;
      background: #EFF6FF;
      border-radius: 8px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--primary-color);
      font-size: 20px;
      font-weight: 700;
      margin-bottom: 18px;
    }
    .feature-card h4 {
      font-size: 18px;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 12px;
    }
    .feature-card p {
      font-size: 14px;
      color: var(--text-muted);
      line-height: 1.6;
      margin: 0;
    }

    /* Section 4: Featured Showcase */
    .game-card {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      display: flex;
      flex-direction: column;
      height: 100%;
    }
    .game-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    .game-cover {
      height: 190px;
      position: relative;
      overflow: hidden;
    }
    .game-cover img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      transition: var(--transition);
    }
    .game-card:hover .game-cover img {
      transform: scale(1.04);
    }
    .game-tag-badge {
      position: absolute;
      top: 12px;
      right: 12px;
      background: rgba(15, 23, 42, 0.85);
      color: #FFFFFF;
      font-size: 12px;
      padding: 4px 10px;
      border-radius: 4px;
      backdrop-filter: blur(4px);
    }
    .game-info {
      padding: 24px;
      display: flex;
      flex-direction: column;
      flex-grow: 1;
    }
    .game-studio {
      font-size: 13px;
      color: var(--text-muted);
      margin-bottom: 6px;
    }
    .game-title {
      font-size: 19px;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 10px;
    }
    .game-desc {
      font-size: 14px;
      color: var(--text-body);
      line-height: 1.6;
      margin-bottom: 18px;
      flex-grow: 1;
    }
    .game-footer {
      display: flex;
      justify-content: space-between;
      align-items: center;
      border-top: 1px solid var(--border-color);
      padding-top: 14px;
      margin-top: auto;
    }
    .game-rating {
      color: var(--accent-color);
      font-weight: 700;
      font-size: 14px;
    }

    /* Section 5: Philosophy & Architecture */
    #philosophy {
      background-color: var(--bg-dark);
      color: #FFFFFF;
    }
    #philosophy .section-tag {
      background: rgba(221, 168, 59, 0.15);
      color: var(--accent-color);
    }
    #philosophy h2 {
      color: #FFFFFF;
    }
    #philosophy .desc {
      color: #94A3B8;
    }
    .pipe-step {
      background: rgba(255, 255, 255, 0.04);
      border: 1px solid rgba(255, 255, 255, 0.08);
      border-radius: var(--radius-md);
      padding: 18px 22px;
      margin-bottom: 14px;
      display: flex;
      gap: 16px;
      align-items: flex-start;
    }
    .step-index {
      width: 32px;
      height: 32px;
      background: var(--primary-color);
      color: #FFFFFF;
      font-weight: 700;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      flex-shrink: 0;
    }
    .step-content h5 {
      font-size: 16px;
      color: #F8FAFC;
      margin: 0 0 6px 0;
    }
    .step-content p {
      font-size: 13px;
      color: #94A3B8;
      margin: 0;
      line-height: 1.5;
    }

    /* Section 6: Developer Stories */
    .story-card {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 30px;
      box-shadow: var(--shadow-sm);
      height: 100%;
    }
    .story-author {
      display: flex;
      align-items: center;
      gap: 14px;
      margin-bottom: 18px;
    }
    .story-avatar {
      width: 52px;
      height: 52px;
      border-radius: 50%;
      border: 2px solid var(--primary-color);
      object-fit: cover;
    }
    .story-author-info h4 {
      font-size: 17px;
      font-weight: 700;
      color: var(--text-main);
      margin: 0 0 4px 0;
    }
    .story-author-info span {
      font-size: 13px;
      color: var(--text-muted);
    }
    .story-quote {
      font-size: 14px;
      color: var(--text-body);
      line-height: 1.7;
      margin-bottom: 20px;
      position: relative;
    }
    .story-stats {
      background: #F1F5F9;
      border-radius: var(--radius-sm);
      padding: 12px 16px;
      display: flex;
      justify-content: space-around;
      text-align: center;
    }
    .story-stats-item strong {
      display: block;
      font-size: 16px;
      color: var(--primary-color);
    }
    .story-stats-item span {
      font-size: 12px;
      color: var(--text-muted);
    }

    /* Section 7: Data Metrics */
    .metrics-bar {
      background: #FFFFFF;
      border-top: 1px solid var(--border-color);
      border-bottom: 1px solid var(--border-color);
      padding: 50px 0;
    }
    .metric-card {
      text-align: center;
      padding: 10px 16px;
    }
    .metric-number {
      font-size: 40px;
      font-weight: 800;
      color: var(--primary-color);
      font-family: Roboto, Arial, sans-serif;
      margin-bottom: 4px;
      line-height: 1.1;
    }
    .metric-label {
      font-size: 15px;
      font-weight: 600;
      color: var(--text-main);
      margin-bottom: 4px;
    }
    .metric-sub {
      font-size: 13px;
      color: var(--text-muted);
    }

    /* Section 8: Reviews */
    .review-card {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 26px;
      box-shadow: var(--shadow-sm);
      height: 100%;
    }
    .review-head {
      display: flex;
      justify-content: space-between;
      align-items: center;
      margin-bottom: 14px;
    }
    .review-source {
      font-weight: 700;
      color: var(--text-main);
      font-size: 15px;
    }
    .review-stars {
      color: var(--accent-color);
      font-size: 14px;
    }
    .review-body {
      font-size: 14px;
      line-height: 1.65;
      color: var(--text-body);
      margin-bottom: 16px;
    }
    .reviewer-meta {
      font-size: 12px;
      color: var(--text-muted);
      border-top: 1px solid #F1F5F9;
      padding-top: 10px;
    }

    /* Section 9: News & Updates */
    .news-card {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      height: 100%;
      display: flex;
      flex-direction: column;
    }
    .news-thumb {
      height: 160px;
      overflow: hidden;
    }
    .news-thumb img {
      width: 100%;
      height: 100%;
      object-fit: cover;
    }
    .news-content {
      padding: 20px;
      flex-grow: 1;
      display: flex;
      flex-direction: column;
    }
    .news-meta {
      display: flex;
      justify-content: space-between;
      font-size: 12px;
      color: var(--text-muted);
      margin-bottom: 10px;
    }
    .news-tag {
      color: var(--primary-color);
      font-weight: 600;
    }
    .news-title {
      font-size: 16px;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 10px;
      line-height: 1.4;
    }
    .news-desc {
      font-size: 13px;
      color: var(--text-muted);
      line-height: 1.6;
      margin-bottom: 16px;
      flex-grow: 1;
    }

    /* Section 10: FAQ Accordion */
    .faq-item {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      margin-bottom: 14px;
      overflow: hidden;
    }
    .faq-title {
      padding: 18px 24px;
      font-size: 16px;
      font-weight: 600;
      color: var(--text-main);
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      background: #FFFFFF;
      user-select: none;
    }
    .faq-title:hover {
      background-color: #F8FAFC;
    }
    .faq-content {
      padding: 0 24px 20px;
      font-size: 14px;
      color: var(--text-body);
      line-height: 1.7;
      display: none;
      border-top: 1px solid #F1F5F9;
      padding-top: 14px;
    }
    .faq-item.active .faq-content {
      display: block;
    }
    .faq-toggle-icon {
      font-weight: 700;
      color: var(--primary-color);
      font-size: 18px;
    }

    /* Section 11: Service Guarantee */
    .guarantee-bar {
      background: #FFFFFF;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 30px 20px;
      box-shadow: var(--shadow-sm);
    }
    .guarantee-item {
      display: flex;
      align-items: center;
      gap: 16px;
    }
    .guarantee-icon {
      width: 44px;
      height: 44px;
      border-radius: 50%;
      background: #E8F0FE;
      color: var(--primary-color);
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      flex-shrink: 0;
    }
    .guarantee-info h5 {
      font-size: 15px;
      font-weight: 700;
      color: var(--text-main);
      margin: 0 0 4px 0;
    }
    .guarantee-info p {
      font-size: 12px;
      color: var(--text-muted);
      margin: 0;
    }

    /* Section 12: Final CTA Form */
    .contact-card {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-sm);
      padding: 40px;
    }
    .form-group {
      margin-bottom: 20px;
    }
    .form-group label {
      display: block;
      font-size: 14px;
      font-weight: 600;
      color: var(--text-main);
      margin-bottom: 6px;
    }
    .form-control {
      width: 100%;
      padding: 12px 14px;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-sm);
      font-size: 14px;
      background: #F8FAFC;
      transition: var(--transition);
    }
    .form-control:focus {
      outline: none;
      border-color: var(--primary-color);
      background: #FFFFFF;
      box-shadow: 0 0 0 3px rgba(27, 79, 147, 0.1);
    }
    textarea.form-control {
      resize: vertical;
      min-height: 100px;
    }

    /* Footer */
    .site-footer {
      background-color: var(--bg-footer);
      color: #94A3B8;
      padding: 60px 0 30px;
      font-size: 14px;
      border-top: 1px solid rgba(255, 255, 255, 0.08);
    }
    .footer-title {
      font-size: 16px;
      font-weight: 700;
      color: #FFFFFF;
      margin-bottom: 18px;
    }
    .footer-links {
      list-style: none;
      margin: 0;
    }
    .footer-links li {
      margin-bottom: 10px;
    }
    .footer-links li a:hover {
      color: #FFFFFF;
    }
    .footer-bottom {
      border-top: 1px solid rgba(255, 255, 255, 0.08);
      margin-top: 40px;
      padding-top: 24px;
      font-size: 12px;
      color: #64748B;
      text-align: center;
    }

    @media (max-width: 1024px) {
      .nav-links {
        display: none;
      }
      .hero-h1 {
        font-size: 32px;
      }
      .section-wrap {
        padding: 50px 0;
      }
    }