/* roulang page: index */
:root {
      --primary: #1A3C40;
      --primary-light: #152F33;
      --accent: #C9A96E;
      --accent-light: #D4BC8A;
      --bg: #FAFAF8;
      --bg-dark: #1A3C40;
      --card-bg: #FFFFFF;
      --card-border: #E8E4DB;
      --text-primary: #1A3C40;
      --text-body: #3D3D3D;
      --text-muted: #6B6B6B;
      --text-on-dark: #FFFFFF;
      --highlight: #B84C3D;
      --divider: #D4CFC4;
      --radius-card: 12px;
      --radius-btn: 8px;
      --shadow-sm: 0 1px 3px rgba(26,60,64,0.06), 0 4px 16px rgba(26,60,64,0.04);
      --shadow-hover: 0 2px 8px rgba(26,60,64,0.10), 0 8px 24px rgba(26,60,64,0.08);
      --font-sans: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
      --font-number: "Inter", "Segoe UI", sans-serif;
    }

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

    body {
      font-family: var(--font-sans);
      background-color: var(--bg);
      color: var(--text-body);
      font-size: 16px;
      line-height: 1.75;
      -webkit-font-smoothing: antialiased;
    }

    h1, h2, h3, h4 {
      font-family: var(--font-sans);
      color: var(--text-primary);
      font-weight: 600;
    }

    h1 {
      font-size: 42px;
      font-weight: 700;
      line-height: 1.2;
      letter-spacing: -0.5px;
    }

    h2 {
      font-size: 32px;
      font-weight: 600;
      line-height: 1.3;
      margin-bottom: 2rem;
    }

    h3 {
      font-size: 20px;
      font-weight: 600;
      line-height: 1.4;
    }

    .section-title {
      position: relative;
      display: inline-block;
      margin-bottom: 3rem;
    }
    .section-title::after {
      content: '';
      position: absolute;
      left: 0;
      bottom: -8px;
      width: 60px;
      height: 2px;
      background: var(--accent);
    }

    p {
      color: var(--text-body);
      line-height: 1.75;
      margin-bottom: 1.5rem;
    }

    a {
      color: var(--primary);
      text-decoration: none;
      transition: color 0.2s;
    }
    a:hover {
      color: var(--primary-light);
    }

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

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

    /* 按钮系统 */
    .btn-primary {
      display: inline-block;
      background: var(--primary);
      color: white;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 16px;
      text-align: center;
      border: none;
      cursor: pointer;
      transition: all 0.25s ease;
      box-shadow: 0 2px 6px rgba(26,60,64,0.15);
      text-decoration: none;
    }
    .btn-primary:hover {
      background: var(--primary-light);
      transform: translateY(-2px);
      box-shadow: 0 8px 20px rgba(26,60,64,0.25);
      color: white;
    }

    .btn-outline {
      display: inline-block;
      background: transparent;
      color: var(--primary);
      border: 2px solid var(--primary);
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 16px;
      text-align: center;
      cursor: pointer;
      transition: all 0.25s ease;
      text-decoration: none;
    }
    .btn-outline:hover {
      background: var(--primary);
      color: white;
      border-color: var(--primary);
      transform: translateY(-2px);
    }

    .btn-light {
      background: transparent;
      border: 2px solid white;
      color: white;
      padding: 14px 38px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 16px;
      transition: 0.25s;
      display: inline-block;
      text-decoration: none;
    }
    .btn-light:hover {
      background: white;
      color: var(--primary);
    }

    /* 导航栏 */
    .custom-nav {
      background: rgba(250,250,248,0.85);
      backdrop-filter: blur(12px);
      border-bottom: 1px solid transparent;
      transition: all 0.3s ease;
      position: fixed;
      top: 0;
      width: 100%;
      z-index: 100;
      height: 72px;
      display: flex;
      align-items: center;
    }
    .custom-nav.scrolled {
      background: rgba(250,250,248,0.98);
      box-shadow: 0 2px 12px rgba(0,0,0,0.04);
      border-bottom: 1px solid var(--card-border);
    }

    .nav-container {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 20px;
    }

    .logo {
      font-size: 22px;
      font-weight: 700;
      color: var(--primary);
      letter-spacing: 1px;
      white-space: nowrap;
    }
    .logo a {
      color: inherit;
      text-decoration: none;
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 28px;
      list-style: none;
      margin: 0;
    }
    .nav-links a {
      font-size: 15px;
      font-weight: 500;
      color: var(--text-body);
      position: relative;
      padding: 8px 0;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary);
      transition: width 0.25s;
    }
    .nav-links a:hover {
      color: var(--primary);
    }
    .nav-links a:hover::after {
      width: 100%;
    }

    .nav-cta {
      margin-left: 12px;
    }
    .nav-cta .btn-primary {
      padding: 10px 22px;
      font-size: 14px;
    }

    .hamburger {
      display: none;
      background: none;
      border: none;
      font-size: 26px;
      color: var(--primary);
      cursor: pointer;
    }

    @media (max-width: 768px) {
      .nav-links {
        display: none;
        position: absolute;
        top: 72px;
        left: 0;
        width: 100%;
        background: rgba(250,250,248,0.98);
        backdrop-filter: blur(12px);
        flex-direction: column;
        padding: 24px 0;
        gap: 20px;
        box-shadow: 0 8px 20px rgba(0,0,0,0.05);
      }
      .nav-links.active {
        display: flex;
      }
      .hamburger {
        display: block;
      }
      .custom-nav {
        height: 60px;
      }
    }

    /* Hero */
    .hero {
      padding: 140px 0 100px;
      background: linear-gradient(135deg, #FAFAF8 0%, #EDF0EE 100%);
      display: flex;
      align-items: center;
    }
    .hero-grid {
      display: flex;
      align-items: center;
      gap: 60px;
    }
    .hero-content {
      flex: 1;
    }
    .hero-image {
      flex: 1;
      text-align: right;
    }
    .hero-image img {
      border-radius: 16px;
      box-shadow: 0 20px 40px rgba(0,0,0,0.08);
      max-width: 100%;
      height: auto;
    }
    .hero-tag {
      font-size: 13px;
      font-weight: 500;
      letter-spacing: 1px;
      color: var(--accent);
      text-transform: uppercase;
      margin-bottom: 16px;
    }
    .hero h1 {
      margin-bottom: 24px;
    }
    .hero-sub {
      font-size: 18px;
      color: var(--text-muted);
      margin-bottom: 32px;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }

    @media (max-width: 768px) {
      .hero-grid {
        flex-direction: column;
      }
      .hero-image {
        order: -1;
        margin-bottom: 32px;
      }
      h1 {
        font-size: 32px;
      }
      .hero {
        padding: 100px 0 60px;
      }
    }

    /* 板块通用 */
    section {
      padding: 100px 0;
    }
    @media (max-width: 768px) {
      section {
        padding: 60px 0;
      }
    }

    .bg-light {
      background: #FFFFFF;
    }
    .bg-dark {
      background: var(--bg-dark);
      color: white;
    }

    /* 核心优势 */
    .advantage-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 30px;
    }
    .adv-card {
      background: transparent;
      padding: 28px 20px;
      border-bottom: 1px solid var(--divider);
      transition: all 0.3s;
      text-align: left;
    }
    .adv-card i {
      font-size: 36px;
      color: var(--primary);
      margin-bottom: 16px;
    }
    .adv-card h3 {
      margin-bottom: 8px;
    }
    .adv-card:hover {
      transform: translateY(-6px);
      border-bottom-color: var(--primary);
    }

    @media (max-width: 1024px) {
      .advantage-grid { grid-template-columns: repeat(2,1fr); }
    }
    @media (max-width: 520px) {
      .advantage-grid { grid-template-columns: 1fr; }
    }

    /* 服务图文 */
    .service-row {
      display: flex;
      align-items: center;
      gap: 60px;
      margin-bottom: 80px;
    }
    .service-img {
      flex: 5;
      border-radius: 12px;
      overflow: hidden;
      box-shadow: var(--shadow-sm);
    }
    .service-text {
      flex: 7;
    }
    .service-text h3 {
      margin: 12px 0 16px;
    }
    .service-list {
      list-style: none;
      padding: 0;
    }
    .service-list li {
      margin-bottom: 10px;
      display: flex;
      align-items: center;
    }
    .service-list i {
      color: var(--primary);
      margin-right: 12px;
    }

    @media (max-width: 768px) {
      .service-row {
        flex-direction: column;
      }
      .service-img {
        margin-bottom: 24px;
      }
    }

    /* 场景卡片 */
    .scene-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 30px;
    }
    .scene-card {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: 0.3s;
    }
    .scene-card img {
      height: 200px;
      object-fit: cover;
      width: 100%;
    }
    .scene-body {
      padding: 20px 24px;
    }
    .scene-card:hover {
      box-shadow: var(--shadow-hover);
    }
    .scene-card:hover img {
      transform: scale(1.03);
      transition: 0.4s;
    }
    @media (max-width: 768px) {
      .scene-grid { grid-template-columns: 1fr; }
    }

    /* 案例数据 */
    .case-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 30px;
    }
    .case-card {
      background: #F7F4EC;
      border-radius: 16px;
      padding: 32px;
      display: flex;
      gap: 30px;
      align-items: center;
    }
    .big-number {
      font-family: var(--font-number);
      font-size: 56px;
      font-weight: 700;
      color: var(--highlight);
      line-height: 1.1;
    }
    @media (max-width: 768px) {
      .case-grid { grid-template-columns: 1fr; }
      .case-card { flex-direction: column; }
    }

    /* FAQ */
    .accordion-item {
      border-bottom: 1px solid var(--card-border);
    }
    .accordion-title {
      font-size: 18px;
      font-weight: 600;
      color: var(--text-primary);
      padding: 20px 0;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }
    .accordion-content {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      color: var(--text-body);
    }
    .accordion-item.active .accordion-content {
      max-height: 200px;
      padding-bottom: 20px;
    }
    .accordion-item.active i {
      transform: rotate(45deg);
    }

    /* CTA 横幅 */
    .cta-banner {
      background: var(--bg-dark);
      padding: 80px 0;
      text-align: center;
    }
    .cta-banner h2 {
      color: white;
    }
    .cta-banner p {
      color: rgba(255,255,255,0.85);
    }

    /* 页脚 */
    .footer {
      background: #2C2C2C;
      color: rgba(255,255,255,0.7);
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 2fr;
      gap: 40px;
    }
    .footer a {
      color: rgba(255,255,255,0.7);
    }
    .footer a:hover {
      color: white;
    }
    .footer-logo {
      font-size: 22px;
      font-weight: 700;
      color: white;
    }
    @media (max-width: 768px) {
      .footer-grid { grid-template-columns: 1fr; }
    }

    .copyright {
      text-align: center;
      margin-top: 40px;
      font-size: 13px;
      color: rgba(255,255,255,0.5);
    }