/* roulang page: index */
:root {
      --primary: #C5E90B;
      --primary-hover: #b0d309;
      --secondary: #1A1A1A;
      --accent-white: #FFFFFF;
      --light-gray: #F5F5F7;
      --text-dark: #1A1A1A;
      --text-body: #555555;
      --text-muted: #777777;
      --border-light: #e0e0e0;
      --radius-md: 12px;
      --radius-xl: 20px;
      --radius-btn: 50px;
      --shadow-card: 0 10px 30px -10px rgba(0,0,0,0.05);
      --shadow-hover: 0 18px 40px -12px rgba(0,0,0,0.12);
      --transition: all 0.25s ease;
      --font-stack: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
    }

    * {
      box-sizing: border-box;
    }

    body {
      font-family: var(--font-stack);
      background-color: var(--accent-white);
      color: var(--text-dark);
      margin: 0;
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
      scroll-behavior: smooth;
    }

    a {
      text-decoration: none;
      color: inherit;
    }

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

    button, .button {
      cursor: pointer;
      font-family: inherit;
      transition: var(--transition);
      border: none;
      outline: none;
    }

    input {
      font-family: inherit;
      outline: none;
    }

    /* 自定义容器 */
    .custom-container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 板块标题统一装饰 */
    .section-title {
      font-size: 42px;
      font-weight: 700;
      line-height: 1.3;
      color: var(--text-dark);
      position: relative;
      padding-left: 24px;
      margin-bottom: 24px;
    }
    .section-title::before {
      content: '';
      position: absolute;
      left: 0;
      top: 8px;
      width: 4px;
      height: 40px;
      background-color: var(--primary);
      border-radius: 2px;
    }

    .section-desc {
      font-size: 18px;
      color: var(--text-body);
      line-height: 1.8;
      margin-bottom: 48px;
    }

    /* 导航栏 */
    #header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 100;
      background: rgba(245, 245, 247, 0.85);
      backdrop-filter: blur(10px);
      -webkit-backdrop-filter: blur(10px);
      box-shadow: 0 2px 12px rgba(0,0,0,0.04);
      transition: var(--transition);
    }
    .header-inner {
      display: flex;
      justify-content: space-between;
      align-items: center;
      padding: 16px 0;
    }
    .logo {
      font-size: 28px;
      font-weight: 800;
      color: var(--secondary);
      letter-spacing: -0.5px;
    }
    .logo span {
      color: var(--primary);
      background: var(--secondary);
      padding: 4px 10px;
      border-radius: 8px;
      margin-left: 6px;
    }
    .nav-links {
      display: flex;
      gap: 32px;
      align-items: center;
    }
    .nav-links a {
      font-weight: 500;
      font-size: 16px;
      color: var(--text-dark);
      position: relative;
      padding: 4px 0;
      transition: var(--transition);
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 3px;
      background: var(--primary);
      border-radius: 2px;
      transition: width 0.2s;
    }
    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 100%;
    }
    .nav-links a:hover {
      color: var(--secondary);
    }
    .hamburger {
      display: none;
      font-size: 28px;
      background: none;
      border: none;
      color: var(--secondary);
    }

    /* 按钮 */
    .btn-primary {
      background: var(--primary);
      color: var(--secondary);
      font-weight: 700;
      padding: 14px 36px;
      border-radius: var(--radius-btn);
      display: inline-block;
      box-shadow: 0 6px 20px rgba(197, 233, 11, 0.3);
      transition: var(--transition);
      font-size: 16px;
    }
    .btn-primary:hover {
      background: var(--primary-hover);
      box-shadow: 0 0 0 4px rgba(197, 233, 11, 0.25);
      color: var(--secondary);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--secondary);
      color: var(--secondary);
      font-weight: 700;
      padding: 14px 36px;
      border-radius: var(--radius-btn);
      display: inline-block;
      transition: var(--transition);
      font-size: 16px;
    }
    .btn-outline:hover {
      border-color: var(--primary);
      color: var(--primary);
    }

    /* Hero */
    #hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      background: radial-gradient(circle at 30% 40%, rgba(0,0,0,0.65) 0%, rgba(26,26,26,0.92) 90%), url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      color: white;
      position: relative;
      margin-top: 0;
      padding-top: 80px;
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 40px;
      align-items: center;
    }
    .hero-left h1 {
      font-size: 56px;
      font-weight: 700;
      line-height: 1.2;
      letter-spacing: -1px;
      color: white;
      margin-bottom: 24px;
    }
    .hero-left .hero-sub {
      font-size: 20px;
      color: rgba(255,255,255,0.8);
      margin-bottom: 40px;
      line-height: 1.7;
    }
    .hero-actions {
      display: flex;
      gap: 20px;
      flex-wrap: wrap;
    }
    .hero-stats {
      display: flex;
      gap: 48px;
      margin-top: 48px;
    }
    .stat-item .stat-number {
      font-size: 44px;
      font-weight: 800;
      color: var(--primary);
    }
    .stat-label {
      color: rgba(255,255,255,0.7);
      font-size: 16px;
    }
    .hero-right {
      display: flex;
      justify-content: center;
    }
    .hero-img-placeholder {
      width: 100%;
      height: 400px;
      background: rgba(255,255,255,0.1);
      border-radius: 24px;
      backdrop-filter: blur(4px);
    }

    /* 核心优势非对称 */
    #advantages {
      background: var(--light-gray);
      padding: 100px 0;
    }
    .adv-grid {
      display: grid;
      grid-template-columns: 280px 1fr;
      gap: 60px;
      align-items: start;
    }
    .adv-left h2 {
      font-size: 42px;
      font-weight: 700;
      line-height: 1.2;
    }
    .adv-items {
      display: flex;
      flex-direction: column;
      gap: 48px;
    }
    .adv-item {
      display: flex;
      gap: 24px;
      align-items: flex-start;
    }
    .adv-dot {
      width: 20px;
      height: 20px;
      background: var(--primary);
      border-radius: 50%;
      margin-top: 6px;
      transition: 0.3s;
      flex-shrink: 0;
    }
    .adv-item:hover .adv-dot {
      transform: scale(1.8);
      background: var(--secondary);
    }

    /* 服务矩阵 */
    #services {
      padding: 100px 0;
      background: white;
    }
    .service-cards {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 32px;
    }
    .service-card {
      background: white;
      border-radius: var(--radius-xl);
      overflow: hidden;
      box-shadow: var(--shadow-card);
      transition: var(--transition);
      display: flex;
      flex-direction: column;
    }
    .service-card:hover {
      transform: translateY(-8px);
      box-shadow: var(--shadow-hover);
      border: 1px solid var(--primary);
    }
    .service-card img {
      width: 100%;
      height: 240px;
      object-fit: cover;
      transition: 0.4s;
    }
    .service-card:hover img {
      transform: scale(1.04);
    }
    .service-text {
      padding: 28px;
    }

    /* 应用场景 */
    #scenarios {
      background: var(--secondary);
      padding: 100px 0;
      color: white;
    }
    .scenario-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .scenario-card {
      height: 320px;
      border-radius: 20px;
      background-size: cover;
      background-position: center;
      position: relative;
      overflow: hidden;
      display: flex;
      align-items: flex-end;
    }
    .scenario-overlay {
      background: rgba(0,0,0,0.65);
      padding: 24px;
      width: 100%;
      transition: 0.3s;
    }
    .scenario-card:hover .scenario-overlay {
      background: rgba(0,0,0,0.4);
    }

    /* 成功案例 */
    #cases {
      background: var(--light-gray);
      padding: 100px 0;
    }
    .cases-flex {
      display: flex;
      gap: 60px;
      align-items: center;
    }
    .big-kpi {
      font-size: 80px;
      font-weight: 800;
      color: var(--primary);
    }
    .client-logos img {
      filter: grayscale(1);
      transition: 0.3s;
      height: 50px;
      margin-right: 24px;
    }
    .client-logos img:hover {
      filter: grayscale(0);
    }

    /* FAQ */
    #faq {
      padding: 100px 0;
    }
    .faq-grid {
      display: grid;
      grid-template-columns: 320px 1fr;
      gap: 48px;
    }
    .accordion-title {
      font-weight: 600;
      background: white;
      border-radius: 12px;
      padding: 20px;
      transition: 0.2s;
    }
    .accordion-title::before {
      content: 'Q';
      font-weight: 800;
      color: var(--primary);
      margin-right: 12px;
    }

    /* CTA */
    #cta {
      background: var(--secondary);
      padding: 100px 0;
      text-align: center;
    }
    .cta-form input {
      padding: 16px 24px;
      border-radius: 50px;
      border: none;
      width: 280px;
    }

    /* Footer */
    footer {
      background: #111;
      color: #ccc;
      padding: 60px 0 20px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 1.5fr 1fr 1fr 1fr;
      gap: 32px;
    }

    /* 响应式 */
    @media (max-width: 1024px) {
      .hero-grid, .adv-grid, .cases-flex, .faq-grid {
        grid-template-columns: 1fr;
      }
      .service-cards, .scenario-grid {
        grid-template-columns: 1fr;
      }
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: block; }
      .section-title { font-size: 32px; }
    }
    @media (max-width: 520px) {
      .hero-left h1 { font-size: 36px; }
      .btn-primary, .btn-outline { padding: 12px 24px; }
    }
    .mobile-menu {
      display: none;
      position: fixed;
      top: 80px;
      left: 0;
      width: 100%;
      background: var(--secondary);
      padding: 32px;
      z-index: 99;
    }
    .mobile-menu a {
      display: block;
      color: var(--primary);
      font-size: 20px;
      margin-bottom: 20px;
    }
    .show-mobile { display: block !important; }