/* roulang page: index */
:root {
      --gold: #D4A017;
      --gold-dark: #B8860B;
      --red: #C41E3A;
      --black: #1A1A1A;
      --warm-white: #F5F3EE;
      --text-dark: #111111;
      --text-body: #333333;
      --text-muted: #666666;
      --border-light: #E0DCD5;
      --white: #FFFFFF;
      --shadow-sm: 0 2px 8px rgba(0,0,0,0.04);
      --shadow-md: 0 8px 24px rgba(0,0,0,0.08);
      --shadow-hover: 0 12px 28px rgba(0,0,0,0.12);
      --radius-sm: 6px;
      --radius-md: 12px;
      --radius-lg: 16px;
      --font-sans: 'PingFang SC', 'Microsoft YaHei', '苹方', '雅黑', system-ui, -apple-system, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
      --transition: 0.25s ease;
    }

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

    body {
      font-family: var(--font-sans);
      background-color: var(--white);
      color: var(--text-body);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }

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

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

    button, input, select, textarea {
      font-family: inherit;
    }

    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }

    /* ---------- 导航栏 ---------- */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 64px;
      background: var(--white);
      box-shadow: 0 1px 6px rgba(0,0,0,0.04);
      display: flex;
      align-items: center;
      z-index: 1000;
      transition: background var(--transition);
    }

    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }

    .logo {
      font-size: 1.45rem;
      font-weight: 700;
      color: var(--text-dark);
      display: flex;
      align-items: center;
      gap: 6px;
      letter-spacing: -0.3px;
    }

    .logo span {
      color: var(--gold);
    }

    .nav-menu {
      display: flex;
      align-items: center;
      gap: 32px;
      list-style: none;
    }

    .nav-menu a {
      font-size: 0.95rem;
      font-weight: 500;
      color: var(--text-body);
      padding: 8px 0;
      position: relative;
    }

    .nav-menu a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 50%;
      width: 0;
      height: 2px;
      background: var(--gold);
      transition: all 0.25s ease;
      transform: translateX(-50%);
    }

    .nav-menu a:hover::after,
    .nav-menu a.active::after {
      width: 100%;
    }

    .nav-menu a:hover {
      color: var(--gold);
    }

    .nav-cta {
      background: var(--gold);
      color: var(--white);
      padding: 10px 20px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      font-size: 0.95rem;
      transition: background 0.2s, transform 0.2s;
      white-space: nowrap;
      border: none;
      cursor: pointer;
    }

    .nav-cta:hover {
      background: var(--gold-dark);
      transform: translateY(-2px);
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      background: transparent;
      border: none;
      cursor: pointer;
      width: 28px;
    }

    .hamburger span {
      height: 3px;
      width: 100%;
      background: var(--text-dark);
      border-radius: 3px;
      transition: all 0.3s;
    }

    @media (max-width: 768px) {
      .nav-menu {
        position: fixed;
        top: 64px;
        left: 0;
        width: 100%;
        background: var(--white);
        flex-direction: column;
        align-items: flex-start;
        padding: 32px 24px;
        gap: 28px;
        box-shadow: 0 10px 20px rgba(0,0,0,0.05);
        transform: translateY(-120%);
        transition: transform 0.3s ease;
        z-index: 999;
      }

      .nav-menu.active {
        transform: translateY(0);
      }

      .hamburger {
        display: flex;
      }

      .nav-cta.desktop-only {
        display: none;
      }

      .nav-menu .nav-cta {
        display: inline-block;
        margin-top: 8px;
      }
    }

    /* ---------- 板块通用 ---------- */
    section {
      padding: 80px 0;
    }

    @media (max-width: 768px) {
      section {
        padding: 50px 0;
      }
    }

    .section-title {
      font-size: 2.2rem;
      font-weight: 700;
      color: var(--text-dark);
      margin-bottom: 16px;
      position: relative;
      display: inline-block;
      letter-spacing: -0.5px;
    }

    .section-title::after {
      content: '';
      display: block;
      width: 50px;
      height: 3px;
      background: var(--gold);
      margin-top: 10px;
      border-radius: 2px;
    }

    .text-center .section-title::after {
      margin-left: auto;
      margin-right: auto;
    }

    /* ---------- Hero ---------- */
    .hero {
      padding-top: 120px;
      padding-bottom: 60px;
      display: flex;
      align-items: center;
      background: var(--white);
    }

    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 40px;
      align-items: center;
    }

    .hero-content h1 {
      font-size: 3.2rem;
      font-weight: 700;
      line-height: 1.2;
      color: var(--text-dark);
      letter-spacing: -0.02em;
      margin-bottom: 20px;
    }

    .hero-content h1 span {
      color: var(--gold);
    }

    .hero-sub {
      font-size: 1.2rem;
      color: var(--text-muted);
      margin-bottom: 32px;
    }

    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }

    .btn-primary {
      background: var(--gold);
      color: var(--white);
      padding: 14px 32px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      transition: 0.2s;
      border: none;
      cursor: pointer;
    }

    .btn-primary:hover {
      background: var(--gold-dark);
      transform: translateY(-2px);
    }

    .btn-outline {
      border: 2px solid var(--gold);
      color: var(--gold);
      padding: 12px 32px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      background: transparent;
      transition: 0.2s;
    }

    .btn-outline:hover {
      background: var(--gold);
      color: var(--white);
    }

    .hero-image img {
      border-radius: var(--radius-lg);
      box-shadow: var(--shadow-md);
      object-fit: cover;
      width: 100%;
    }

    @media (max-width: 768px) {
      .hero-grid {
        grid-template-columns: 1fr;
      }
      .hero-content h1 {
        font-size: 2.5rem;
      }
      .hero-image {
        order: -1;
      }
    }

    /* ---------- 核心优势 数据卡片 ---------- */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      margin-top: 40px;
    }

    .feature-card {
      background: var(--warm-white);
      padding: 32px 24px;
      border-radius: var(--radius-md);
      text-align: center;
      box-shadow: var(--shadow-sm);
      transition: all 0.3s;
      border: 1px solid var(--border-light);
    }

    .feature-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
    }

    .feature-number {
      font-size: 3rem;
      font-weight: 800;
      color: var(--gold);
      line-height: 1.2;
    }

    .feature-card:hover .feature-number {
      color: var(--red);
    }

    .feature-title {
      font-weight: 700;
      font-size: 1.4rem;
      margin: 12px 0 8px;
    }

    .feature-desc {
      color: var(--text-muted);
      font-size: 0.95rem;
    }

    @media (max-width: 768px) {
      .features-grid {
        grid-template-columns: 1fr;
      }
    }

    /* ---------- 服务项目 标签切换 ---------- */
    .services-layout {
      display: flex;
      gap: 32px;
      margin-top: 40px;
    }

    .service-tabs {
      display: flex;
      flex-direction: column;
      min-width: 180px;
      gap: 8px;
    }

    .tab-btn {
      background: transparent;
      border: none;
      padding: 12px 20px;
      font-weight: 600;
      color: var(--text-muted);
      border-left: 3px solid transparent;
      text-align: left;
      cursor: pointer;
      transition: 0.2s;
      font-size: 1rem;
    }

    .tab-btn.active {
      color: var(--gold);
      border-left-color: var(--gold);
      background: rgba(212,160,23,0.05);
    }

    .service-detail {
      flex: 1;
      display: flex;
      gap: 24px;
      background: var(--white);
      border: 1px solid var(--border-light);
      border-radius: var(--radius-md);
      padding: 24px;
      box-shadow: var(--shadow-sm);
    }

    .service-detail img {
      width: 180px;
      height: 140px;
      object-fit: cover;
      border-radius: var(--radius-sm);
    }

    .service-info h3 {
      font-size: 1.8rem;
      font-weight: 700;
    }

    .service-list {
      margin-top: 12px;
      list-style: none;
    }

    .service-list li::before {
      content: "●";
      color: var(--gold);
      margin-right: 8px;
    }

    @media (max-width: 768px) {
      .services-layout {
        flex-direction: column;
      }
      .service-tabs {
        flex-direction: row;
        overflow-x: auto;
      }
      .service-detail {
        flex-direction: column;
      }
    }

    /* ---------- 案例瀑布流 ---------- */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      margin-top: 40px;
    }

    .case-card {
      border-radius: var(--radius-md);
      overflow: hidden;
      background: var(--white);
      border: 1px solid var(--border-light);
      transition: all 0.3s;
    }

    .case-card:hover {
      transform: translateY(-5px);
      box-shadow: var(--shadow-md);
    }

    .case-img {
      height: 200px;
      overflow: hidden;
    }

    .case-img img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      transition: transform 0.4s;
    }

    .case-card:hover .case-img img {
      transform: scale(1.05);
    }

    .case-info {
      padding: 16px;
    }

    .tag {
      color: var(--red);
      font-size: 0.8rem;
      font-weight: 600;
    }

    @media (max-width: 992px) {
      .cases-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }

    @media (max-width: 520px) {
      .cases-grid {
        grid-template-columns: 1fr;
      }
    }

    /* 表格对比 */
    .compare-table {
      width: 100%;
      border-collapse: collapse;
      margin-top: 30px;
    }

    .compare-table th {
      background: var(--black);
      color: white;
      padding: 16px;
    }

    .compare-table td, .compare-table th {
      padding: 14px;
      border: 1px solid var(--border-light);
    }

    .highlight-col {
      background: rgba(212,160,23,0.06);
    }

    @media (max-width: 768px) {
      .compare-table, .compare-table tbody, .compare-table tr, .compare-table td {
        display: block;
      }
      .compare-table thead {
        display: none;
      }
      .compare-table tr {
        margin-bottom: 12px;
      }
    }

    /* FAQ */
    .faq-item {
      border-bottom: 1px solid var(--border-light);
      padding: 18px 0;
    }

    .faq-question {
      font-weight: 700;
      display: flex;
      justify-content: space-between;
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      color: var(--text-body);
    }

    /* CTA */
    .cta-section {
      background: var(--gold);
      color: var(--white);
    }

    .cta-form input, .cta-form select {
      width: 100%;
      padding: 14px;
      border-radius: var(--radius-sm);
      border: none;
      margin-bottom: 12px;
    }

    .footer {
      background: var(--black);
      color: #ccc;
      padding: 40px 0 20px;
    }

    .footer a:hover {
      color: var(--gold);
    }

    .footer-grid {
      display: grid;
      grid-template-columns: repeat(4,1fr);
      gap: 24px;
    }

    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr;
      }
    }