/* roulang page: index */
:root {
      --primary: #1B2A4A;
      --accent: #C75B39;
      --gold: #C9A96E;
      --bg-body: #F9F7F4;
      --bg-card: #FFFFFF;
      --bg-dark: #0F1A2E;
      --text-primary: #1E1E1E;
      --text-secondary: #5A5A5A;
      --text-on-dark: #E8E4DD;
      --border-light: rgba(27,42,74,0.08);
      --shadow-card: 0 4px 20px rgba(27,42,74,0.06);
      --shadow-hover: 0 12px 32px rgba(27,42,74,0.12);
      --radius-card: 20px;
      --radius-btn: 12px;
      --radius-badge: 24px;
      --transition: 0.25s ease;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Noto Sans SC", system-ui, -apple-system, sans-serif;
      --section-padding: clamp(60px, 8vw, 100px);
    }

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

    html {
      scroll-behavior: smooth;
      font-size: 16px;
    }

    body {
      font-family: var(--font-sans);
      background-color: var(--bg-body);
      color: var(--text-primary);
      line-height: 1.75;
      -webkit-font-smoothing: antialiased;
      display: flex;
      flex-direction: column;
      min-height: 100vh;
    }

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

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

    button, .btn {
      cursor: pointer;
      font-family: inherit;
      border: none;
      background: transparent;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 0.5rem;
      transition: all var(--transition);
      font-weight: 600;
    }

    .container {
      width: 100%;
      max-width: 1280px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 24px;
      padding-right: 24px;
    }

    .section {
      padding-top: var(--section-padding);
      padding-bottom: var(--section-padding);
    }

    .sr-only {
      position: absolute;
      width: 1px;
      height: 1px;
      padding: 0;
      margin: -1px;
      overflow: hidden;
      clip: rect(0,0,0,0);
      border: 0;
    }

    /* 导航 */
    .navbar {
      position: sticky;
      top: 0;
      z-index: 50;
      background-color: rgba(255,255,255,0.92);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      border-bottom: 1px solid var(--border-light);
      box-shadow: 0 1px 8px rgba(0,0,0,0.02);
    }

    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
    }

    .logo {
      display: flex;
      align-items: center;
      gap: 10px;
      font-weight: 700;
      font-size: 1.5rem;
      color: var(--primary);
    }
    .logo-icon {
      width: 36px;
      height: 36px;
      background: linear-gradient(135deg, var(--primary), var(--accent));
      border-radius: 10px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: white;
      font-size: 1.2rem;
      font-weight: 700;
    }

    .nav-menu {
      display: flex;
      align-items: center;
      gap: 2rem;
      list-style: none;
    }

    .nav-link {
      font-weight: 500;
      color: var(--text-primary);
      position: relative;
      padding: 0.25rem 0;
    }
    .nav-link::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--accent);
      transition: width var(--transition);
    }
    .nav-link:hover::after,
    .nav-link.active::after {
      width: 100%;
    }

    .btn-primary {
      background: var(--accent);
      color: white;
      padding: 0.7rem 1.8rem;
      border-radius: var(--radius-btn);
      font-weight: 600;
      letter-spacing: 0.3px;
    }
    .btn-primary:hover {
      background: #A84A2D;
      transform: translateY(-1px);
      box-shadow: 0 8px 18px rgba(199,91,57,0.3);
    }

    .btn-outline {
      background: transparent;
      border: 1.5px solid var(--primary);
      color: var(--primary);
      padding: 0.7rem 1.8rem;
      border-radius: var(--radius-btn);
      font-weight: 600;
    }
    .btn-outline:hover {
      background: var(--primary);
      color: white;
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      background: transparent;
      border: none;
    }
    .hamburger span {
      width: 26px;
      height: 2px;
      background: var(--primary);
      border-radius: 2px;
      transition: var(--transition);
    }

    /* Hero */
    .hero {
      display: flex;
      align-items: center;
      gap: 3rem;
      min-height: 85vh;
      padding-top: 1rem;
      padding-bottom: 2rem;
    }
    .hero-left {
      flex: 1 1 50%;
    }
    .hero-right {
      flex: 1 1 50%;
      position: relative;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      border-radius: var(--radius-card);
      min-height: 420px;
      overflow: hidden;
      box-shadow: var(--shadow-card);
    }
    .hero-overlay {
      position: absolute;
      inset: 0;
      background: linear-gradient(135deg, rgba(27,42,74,0.7) 0%, rgba(15,26,46,0.4) 100%);
    }
    .hero-card {
      position: absolute;
      bottom: 30px;
      right: 30px;
      background: rgba(255,255,255,0.9);
      backdrop-filter: blur(8px);
      border-radius: 18px;
      padding: 1.5rem;
      max-width: 240px;
      color: var(--primary);
      font-weight: 600;
      border: 1px solid var(--gold);
    }

    h1 {
      font-size: clamp(2.5rem, 5vw, 3.8rem);
      font-weight: 700;
      color: var(--primary);
      line-height: 1.2;
      letter-spacing: -0.02em;
      margin-bottom: 1.5rem;
    }
    .hero-sub {
      font-size: 1.2rem;
      color: var(--text-secondary);
      margin-bottom: 2.5rem;
    }
    .hero-cta {
      display: flex;
      gap: 1rem;
      flex-wrap: wrap;
    }

    /* 板块标题 */
    .section-title {
      font-size: 2rem;
      font-weight: 600;
      color: var(--primary);
      margin-bottom: 0.75rem;
      display: flex;
      align-items: center;
      gap: 0.5rem;
    }
    .section-title::before {
      content: '';
      display: inline-block;
      width: 6px;
      height: 28px;
      background: var(--gold);
      border-radius: 4px;
    }
    .section-lead {
      color: var(--text-secondary);
      max-width: 700px;
      margin-bottom: 3rem;
    }

    /* 卡片网格 */
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 24px;
    }
    .advantage-card {
      background: var(--bg-card);
      border-radius: var(--radius-card);
      padding: 2rem 1.5rem;
      box-shadow: var(--shadow-card);
      transition: all var(--transition);
      text-align: center;
    }
    .advantage-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    .advantage-icon {
      width: 56px;
      height: 56px;
      margin: 0 auto 1.25rem;
      color: var(--accent);
      font-size: 2.2rem;
      display: flex;
      align-items: center;
      justify-content: center;
      border: 1px solid var(--gold);
      border-radius: 16px;
      background: #fdf8f2;
    }

    /* 数据带 */
    .stats-band {
      background: var(--primary);
      padding: 2.5rem 0;
      color: white;
    }
    .stats-grid {
      display: flex;
      justify-content: space-around;
      text-align: center;
      flex-wrap: wrap;
      gap: 1.5rem;
    }
    .stat-item {
      flex: 1 1 140px;
    }
    .stat-number {
      font-size: 2.5rem;
      font-weight: 800;
      color: var(--gold);
    }

    /* 服务双列卡片 */
    .service-row {
      display: flex;
      flex-direction: column;
      gap: 24px;
    }
    .service-card {
      display: flex;
      background: var(--bg-card);
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-card);
      transition: var(--transition);
    }
    .service-card:hover {
      box-shadow: var(--shadow-hover);
    }
    .service-img {
      width: 260px;
      flex-shrink: 0;
      object-fit: cover;
    }
    .service-body {
      padding: 2rem;
      display: flex;
      flex-direction: column;
      justify-content: center;
    }
    .service-body h3 {
      font-size: 1.35rem;
      margin-bottom: 0.5rem;
    }
    .service-link {
      color: var(--accent);
      font-weight: 600;
      margin-top: 1rem;
      display: inline-flex;
      align-items: center;
      gap: 4px;
    }

    /* 流程 */
    .process-steps {
      display: flex;
      justify-content: space-between;
      text-align: center;
      position: relative;
      gap: 1.5rem;
      flex-wrap: wrap;
    }
    .step {
      flex: 1 1 160px;
    }
    .step-circle {
      width: 50px;
      height: 50px;
      background: var(--accent);
      color: white;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      font-size: 1.3rem;
      margin: 0 auto 0.8rem;
    }

    /* 案例 */
    .case-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 24px;
    }
    .case-card {
      border-radius: var(--radius-card);
      overflow: hidden;
      position: relative;
      box-shadow: var(--shadow-card);
    }
    .case-img {
      aspect-ratio: 16/9;
      object-fit: cover;
      width: 100%;
    }
    .case-tag {
      position: absolute;
      bottom: 15px;
      left: 15px;
      background: rgba(255,255,255,0.9);
      padding: 0.3rem 1rem;
      border-radius: 20px;
      border: 1px solid var(--gold);
      font-weight: 600;
      color: var(--primary);
    }

    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
      display: flex;
      flex-direction: column;
      gap: 12px;
    }
    .faq-item {
      background: var(--bg-card);
      border-radius: 16px;
      border: 1px solid var(--border-light);
    }
    .faq-question {
      width: 100%;
      padding: 1.2rem 1.5rem;
      display: flex;
      justify-content: space-between;
      font-weight: 600;
      background: transparent;
      font-size: 1.05rem;
    }
    .faq-answer {
      padding: 0 1.5rem 1.2rem;
      color: var(--text-secondary);
      display: none;
    }
    .faq-item.open .faq-answer {
      display: block;
    }
    .faq-item.open .faq-icon {
      transform: rotate(45deg);
    }

    /* CTA */
    .cta-dark {
      background: var(--bg-dark);
      color: white;
      text-align: center;
      padding: 5rem 1.5rem;
      border-radius: 28px;
      margin: 0 24px;
    }

    /* 页脚 */
    .footer {
      background: var(--primary);
      color: var(--text-on-dark);
      padding: 3rem 0 1.5rem;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1.5fr;
      gap: 2rem;
    }
    .footer a {
      color: var(--text-on-dark);
      opacity: 0.8;
      display: block;
      margin-bottom: 0.4rem;
    }
    .footer a:hover {
      opacity: 1;
      color: var(--gold);
    }

    @media (max-width: 1024px) {
      .grid-3, .case-grid {
        grid-template-columns: repeat(2,1fr);
      }
      .service-card {
        flex-direction: column;
      }
      .service-img {
        width: 100%;
        height: 200px;
      }
    }

    @media (max-width: 768px) {
      .nav-menu {
        display: none;
        flex-direction: column;
        position: absolute;
        top: 72px;
        left: 0;
        width: 100%;
        background: white;
        padding: 2rem;
        box-shadow: var(--shadow-card);
      }
      .nav-menu.active {
        display: flex;
      }
      .hamburger {
        display: flex;
      }
      .hero {
        flex-direction: column;
        min-height: auto;
      }
      .hero-right {
        width: 100%;
        min-height: 300px;
      }
      .grid-3, .case-grid, .footer-grid {
        grid-template-columns: 1fr;
      }
      .stats-grid {
        flex-direction: column;
      }
    }