/* roulang page: index */
:root {
      --primary-black: #1A1A1A;
      --champagne-gold: #C8A96E;
      --metallic-gold: #D4AF37;
      --warm-white: #F5F3EF;
      --dark-card: #2A2A2A;
      --light-text: #E0D6C2;
      --dark-title: #2C2C2C;
      --dark-body: #5A5A5A;
      --border-gold: rgba(200,169,110,0.3);
      --border-dark: #3A3A3A;
      --radius-card: 8px;
      --radius-btn: 6px;
      --shadow-light: 0 4px 20px rgba(0,0,0,0.06);
      --font-sans: 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
    }

    * {
      box-sizing: border-box;
    }

    body {
      font-family: var(--font-sans);
      background-color: var(--primary-black);
      color: var(--light-text);
      margin: 0;
      line-height: 1.7;
      -webkit-font-smoothing: antialiased;
    }

    img {
      max-width: 100%;
      height: auto;
      display: block;
      border-radius: var(--radius-card);
    }

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

    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 20px;
    }

    /* 导航栏 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: rgba(26, 26, 26, 0.92);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      z-index: 100;
      border-bottom: 1px solid var(--border-gold);
    }

    .nav-container {
      display: flex;
      align-items: center;
      justify-content: center;
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 20px;
      position: relative;
    }

    .nav-left, .nav-right {
      display: flex;
      align-items: center;
      gap: 28px;
      flex: 1;
    }

    .nav-left {
      justify-content: flex-end;
    }

    .nav-right {
      justify-content: flex-start;
    }

    .nav-link {
      font-weight: 500;
      font-size: 15px;
      color: var(--light-text);
      letter-spacing: 0.3px;
      position: relative;
      padding: 28px 0;
      transition: color 0.2s;
    }

    .nav-link:hover,
    .nav-link.active {
      color: var(--champagne-gold);
    }

    .logo-center {
      flex-shrink: 0;
      padding: 0 32px;
      font-size: 24px;
      font-weight: 700;
      color: var(--champagne-gold);
      letter-spacing: 1px;
      white-space: nowrap;
      line-height: 1.2;
    }

    .logo-diamond {
      display: inline-block;
      width: 10px;
      height: 10px;
      background: var(--metallic-gold);
      transform: rotate(45deg);
      margin-right: 8px;
      vertical-align: middle;
    }

    .menu-toggle {
      display: none;
      background: none;
      border: none;
      color: var(--champagne-gold);
      font-size: 28px;
      cursor: pointer;
      padding: 14px 0;
    }

    .mobile-menu {
      display: none;
      position: fixed;
      top: 72px;
      left: 0;
      width: 100%;
      background: var(--primary-black);
      flex-direction: column;
      padding: 20px;
      border-bottom: 1px solid var(--border-gold);
      z-index: 99;
    }

    .mobile-menu a {
      padding: 14px 10px;
      font-size: 18px;
      font-weight: 500;
      color: var(--light-text);
      border-bottom: 1px solid rgba(255,255,255,0.08);
    }

    /* Hero */
    .hero {
      background: linear-gradient(180deg, #1A1A1A 0%, #252525 100%);
      min-height: 90vh;
      display: flex;
      align-items: center;
      padding: 120px 0 80px;
      position: relative;
      overflow: hidden;
    }

    .hero .container {
      display: flex;
      align-items: center;
      gap: 50px;
    }

    .hero-text {
      flex: 1;
    }

    .hero-label {
      display: inline-block;
      border-left: 3px solid var(--champagne-gold);
      padding-left: 14px;
      color: var(--metallic-gold);
      font-weight: 500;
      margin-bottom: 20px;
      font-size: 16px;
    }

    .hero h1 {
      font-size: 50px;
      font-weight: 700;
      color: #FFFFFF;
      line-height: 1.25;
      margin-bottom: 22px;
      letter-spacing: -0.5px;
    }

    .hero-sub {
      font-size: 19px;
      color: var(--light-text);
      margin-bottom: 36px;
      line-height: 1.6;
      max-width: 500px;
    }

    .hero-buttons {
      display: flex;
      gap: 18px;
      flex-wrap: wrap;
    }

    .btn-primary {
      background: var(--champagne-gold);
      color: var(--primary-black);
      font-weight: 600;
      padding: 14px 36px;
      border-radius: var(--radius-btn);
      display: inline-block;
      font-size: 16px;
      transition: background 0.3s, transform 0.2s;
      border: none;
      cursor: pointer;
      text-align: center;
    }

    .btn-primary:hover {
      background: #B8914D;
      transform: translateY(-2px);
    }

    .btn-secondary {
      background: transparent;
      border: 1px solid var(--champagne-gold);
      color: var(--champagne-gold);
      font-weight: 500;
      padding: 14px 36px;
      border-radius: var(--radius-btn);
      display: inline-block;
      font-size: 16px;
      transition: all 0.3s;
      cursor: pointer;
    }

    .btn-secondary:hover {
      background: rgba(200,169,110,0.1);
    }

    .hero-image {
      flex: 1;
      display: flex;
      justify-content: center;
    }

    .hero-image img {
      max-height: 480px;
      object-fit: cover;
      border-radius: 16px;
      box-shadow: 0 20px 40px rgba(0,0,0,0.5);
      border: 1px solid rgba(200,169,110,0.25);
    }

    /* 通用板块 */
    section {
      padding: 90px 0;
    }

    .section-title {
      text-align: center;
      margin-bottom: 50px;
    }

    .section-title h2 {
      font-size: 38px;
      font-weight: 600;
      color: #FFFFFF;
      margin-bottom: 12px;
    }

    .light-section h2 {
      color: var(--dark-title);
    }

    .section-subtitle {
      color: var(--champagne-gold);
      font-size: 18px;
    }

    .light-section {
      background-color: var(--warm-white);
      color: var(--dark-body);
    }

    .dark-section {
      background-color: var(--primary-black);
    }

    /* 核心优势 */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 28px;
    }

    .feature-card {
      background: #FFFFFF;
      padding: 32px 20px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-light);
      text-align: center;
      transition: transform 0.3s, border-color 0.3s;
      border: 1px solid transparent;
    }

    .feature-card:hover {
      transform: translateY(-6px);
      border-color: var(--champagne-gold);
    }

    .feature-icon {
      font-size: 36px;
      color: var(--champagne-gold);
      margin-bottom: 20px;
    }

    .feature-card h3 {
      font-size: 22px;
      font-weight: 600;
      color: var(--dark-title);
      margin-bottom: 10px;
    }

    .feature-card p {
      color: var(--dark-body);
      font-size: 15px;
    }

    /* 产品服务卡片 */
    .services-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 30px;
    }

    .service-card {
      background: var(--dark-card);
      border-radius: var(--radius-card);
      overflow: hidden;
      border: 1px solid rgba(200,169,110,0.2);
      transition: transform 0.3s, border-color 0.3s;
    }

    .service-card:hover {
      transform: translateY(-6px);
      border-color: var(--champagne-gold);
    }

    .service-card img {
      width: 100%;
      height: 200px;
      object-fit: cover;
    }

    .service-content {
      padding: 24px;
    }

    .service-content h3 {
      font-size: 22px;
      font-weight: 600;
      color: #FFFFFF;
      margin-bottom: 8px;
    }

    .service-content p {
      color: var(--light-text);
      margin-bottom: 18px;
    }

    .service-link {
      color: var(--champagne-gold);
      font-weight: 500;
      border-bottom: 1px solid transparent;
    }

    .service-link:hover {
      border-bottom-color: var(--champagne-gold);
    }

    /* 数据背书 */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
      text-align: center;
    }

    .stat-number {
      font-size: 48px;
      font-weight: 700;
      color: var(--metallic-gold);
      line-height: 1.1;
    }

    .stat-label {
      color: var(--light-text);
      font-size: 16px;
      margin-top: 8px;
    }

    /* 案例展示 */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 30px;
    }

    .case-card {
      background: #FFFFFF;
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-light);
      transition: transform 0.3s;
      border: 1px solid transparent;
    }

    .case-card:hover {
      transform: translateY(-5px);
      border-color: var(--champagne-gold);
    }

    .case-card img {
      height: 240px;
      width: 100%;
      object-fit: cover;
    }

    .case-info {
      padding: 24px;
    }

    .case-info h3 {
      color: var(--dark-title);
      font-weight: 600;
    }

    /* 流程 */
    .process-steps {
      display: flex;
      justify-content: space-between;
      align-items: flex-start;
    }

    .step {
      text-align: center;
      flex: 1;
      position: relative;
    }

    .step-number {
      width: 50px;
      height: 50px;
      background: var(--champagne-gold);
      color: var(--primary-black);
      font-weight: 700;
      font-size: 22px;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      margin: 0 auto 16px;
    }

    .step h3 {
      color: var(--dark-title);
    }

    /* FAQ */
    .faq-item {
      background: var(--dark-card);
      border-radius: var(--radius-card);
      margin-bottom: 12px;
      border: 1px solid transparent;
    }

    .faq-question {
      padding: 20px 24px;
      font-weight: 500;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      color: #FFFFFF;
    }

    .faq-answer {
      padding: 0 24px 20px;
      color: var(--light-text);
      display: none;
    }

    .faq-item.active .faq-answer {
      display: block;
    }

    .faq-item.active {
      border-color: var(--champagne-gold);
    }

    /* CTA */
    .cta-section {
      background: var(--primary-black);
      text-align: center;
    }

    /* 页脚 */
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }

    .footer-logo {
      font-size: 22px;
      font-weight: 700;
      color: var(--champagne-gold);
    }

    .footer-copy {
      border-top: 1px solid var(--border-gold);
      margin-top: 40px;
      padding-top: 20px;
      text-align: center;
      color: #aaa;
    }

    @media (max-width: 1024px) {
      .nav-left, .nav-right { gap: 16px; }
      .features-grid { grid-template-columns: repeat(2,1fr); }
      .services-grid { grid-template-columns: 1fr 1fr; }
    }

    @media (max-width: 768px) {
      .nav-left, .nav-right { display: none; }
      .menu-toggle { display: block; }
      .logo-center { padding: 0; }
      .hero .container { flex-direction: column; }
      .hero h1 { font-size: 36px; }
      .services-grid, .cases-grid, .stats-grid { grid-template-columns: 1fr; }
      .process-steps { flex-direction: column; gap: 30px; }
      .footer-grid { grid-template-columns: 1fr; }
    }