/* roulang page: index */
:root {
      --color-primary: #0E3B43;
      --color-primary-dark: #09181B;
      --color-primary-light: #18525D;
      --color-accent-gold: #C68A4C;
      --color-accent-blue: #1D6388;
      --color-bg-clean: #F7F9FA;
      --color-text-main: #1D292C;
      --color-text-muted: #596E73;
      --color-border-subtle: #E2E8EA;
      --radius-sm: 4px;
      --radius-md: 6px;
      --shadow-light: 0 1px 3px rgba(0,0,0,0.05), 0 10px 15px -5px rgba(0,0,0,0.04);
      --shadow-hover: 0 4px 6px -1px rgba(0,0,0,0.1), 0 20px 25px -5px rgba(0,0,0,0.08);
      --transition-base: all 0.25s ease-in-out;
    }

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

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

    body {
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
      line-height: 1.75;
      color: var(--color-text-main);
      background-color: var(--color-bg-clean);
      -webkit-font-smoothing: antialiased;
    }

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

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

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

    .container {
      width: 100%;
      max-width: 1280px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 1.5rem;
      padding-right: 1.5rem;
    }

    .section-py {
      padding-top: 5rem;
      padding-bottom: 5rem;
    }

    .section-py-sm {
      padding-top: 3rem;
      padding-bottom: 3rem;
    }

    .section-title-wrap {
      margin-bottom: 3rem;
      max-width: 800px;
    }

    .section-tag {
      display: inline-block;
      font-size: 0.8125rem;
      font-weight: 600;
      letter-spacing: 0.05em;
      color: var(--color-accent-gold);
      text-transform: uppercase;
      margin-bottom: 0.5rem;
      padding: 0.2rem 0.6rem;
      background: rgba(198, 138, 76, 0.1);
      border-radius: var(--radius-sm);
      border-left: 3px solid var(--color-accent-gold);
    }

    .section-title {
      font-size: 2.125rem;
      font-weight: 700;
      color: var(--color-primary);
      line-height: 1.35;
      margin-bottom: 1rem;
    }

    .section-desc {
      font-size: 1.0625rem;
      color: var(--color-text-muted);
      line-height: 1.8;
    }

    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 0.75rem 1.625rem;
      font-size: 0.9375rem;
      font-weight: 600;
      border-radius: var(--radius-sm);
      cursor: pointer;
      transition: var(--transition-base);
      border: 1px solid transparent;
      gap: 0.5rem;
    }

    .btn-gold {
      background-color: var(--color-accent-gold);
      color: #ffffff;
      border-color: var(--color-accent-gold);
    }

    .btn-gold:hover {
      background-color: #b0763b;
      box-shadow: 0 4px 12px rgba(198, 138, 76, 0.3);
    }

    .btn-primary {
      background-color: var(--color-primary);
      color: #ffffff;
    }

    .btn-primary:hover {
      background-color: var(--color-primary-light);
    }

    .btn-outline {
      background-color: transparent;
      border-color: var(--color-primary);
      color: var(--color-primary);
    }

    .btn-outline:hover {
      background-color: var(--color-primary);
      color: #ffffff;
    }

    .btn-outline-white {
      background-color: transparent;
      border-color: rgba(255, 255, 255, 0.4);
      color: #ffffff;
    }

    .btn-outline-white:hover {
      background-color: #ffffff;
      color: var(--color-primary-dark);
    }

    /* 顶部导航 */
    .top-bar {
      background-color: var(--color-primary-dark);
      color: #A3B5B8;
      font-size: 0.75rem;
      padding: 0.45rem 0;
      border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    }

    .top-bar-inner {
      display: flex;
      justify-content: space-between;
      align-items: center;
      flex-wrap: wrap;
      gap: 0.5rem;
    }

    .main-nav {
      background: #ffffff;
      border-bottom: 1px solid var(--color-border-subtle);
      position: sticky;
      top: 0;
      z-index: 1000;
      box-shadow: 0 2px 8px rgba(0,0,0,0.03);
    }

    .nav-inner {
      display: flex;
      justify-content: space-between;
      align-items: center;
      height: 70px;
    }

    .nav-logo {
      display: flex;
      align-items: center;
      gap: 0.75rem;
      font-size: 1.25rem;
      font-weight: 700;
      color: var(--color-primary);
    }

    .nav-logo-icon {
      width: 32px;
      height: 32px;
      background: var(--color-primary);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      color: #ffffff;
      position: relative;
    }

    .nav-logo-icon::after {
      content: "";
      width: 14px;
      height: 14px;
      border: 2px solid var(--color-accent-gold);
      border-radius: 50%;
      position: absolute;
    }

    .nav-links {
      display: flex;
      align-items: center;
      list-style: none;
      gap: 1.5rem;
    }

    .nav-links a {
      font-size: 0.9375rem;
      font-weight: 500;
      color: #334447;
      padding: 0.4rem 0.2rem;
      position: relative;
    }

    .nav-links a:hover, .nav-links a.active {
      color: var(--color-accent-gold);
    }

    .nav-links a.active::after {
      content: "";
      position: absolute;
      bottom: -4px;
      left: 0;
      right: 0;
      height: 2px;
      background: var(--color-accent-gold);
    }

    .mobile-menu-btn {
      display: none;
      background: none;
      border: none;
      font-size: 1.5rem;
      color: var(--color-primary);
      cursor: pointer;
    }

    /* 首屏 Hero */
    .hero-section {
      position: relative;
      background-color: var(--color-primary-dark);
      color: #ffffff;
      min-height: 600px;
      display: flex;
      align-items: center;
      overflow: hidden;
    }

    .hero-bg-media {
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      object-fit: cover;
      opacity: 0.28;
      filter: saturate(0.8) contrast(1.1);
    }

    .hero-overlay {
      position: absolute;
      inset: 0;
      background: linear-gradient(90deg, rgba(9,24,27,0.96) 0%, rgba(9,24,27,0.85) 55%, rgba(9,24,27,0.4) 100%);
    }

    .hero-content {
      position: relative;
      z-index: 10;
      max-width: 820px;
      padding: 4.5rem 0;
    }

    .hero-badge-wrap {
      display: flex;
      align-items: center;
      gap: 0.75rem;
      margin-bottom: 1.5rem;
    }

    .hero-badge {
      background: rgba(198, 138, 76, 0.2);
      border: 1px solid var(--color-accent-gold);
      color: var(--color-accent-gold);
      padding: 0.25rem 0.75rem;
      font-size: 0.8125rem;
      border-radius: var(--radius-sm);
      font-weight: 600;
    }

    .hero-cert {
      color: #9ab4b9;
      font-size: 0.8125rem;
      border-left: 1px solid rgba(255,255,255,0.2);
      padding-left: 0.75rem;
    }

    .hero-title {
      font-size: 2.75rem;
      line-height: 1.25;
      font-weight: 800;
      margin-bottom: 1.25rem;
      letter-spacing: -0.02em;
    }

    .hero-title span {
      color: var(--color-accent-gold);
    }

    .hero-subtitle {
      font-size: 1.125rem;
      line-height: 1.85;
      color: #C0CFD2;
      margin-bottom: 2.25rem;
    }

    .hero-btns {
      display: flex;
      flex-wrap: wrap;
      gap: 1rem;
    }

    /* 模块通用卡片 */
    .card-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
      gap: 1.5rem;
    }

    .card-base {
      background: #ffffff;
      border: 1px solid var(--color-border-subtle);
      border-radius: var(--radius-md);
      padding: 1.875rem;
      box-shadow: var(--shadow-light);
      transition: var(--transition-base);
    }

    .card-base:hover {
      box-shadow: var(--shadow-hover);
      border-color: #cbd8db;
      transform: translateY(-2px);
    }

    /* 左右图文布局 */
    .split-layout {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 3.5rem;
      align-items: center;
    }

    .split-media img {
      width: 100%;
      height: 380px;
      object-fit: cover;
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-light);
      border: 1px solid var(--color-border-subtle);
    }

    /* 深色对比模块 */
    .dark-showcase {
      background-color: var(--color-primary-dark);
      color: #ffffff;
      border-top: 1px solid rgba(255, 255, 255, 0.08);
      border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    }

    .dark-showcase .section-title {
      color: #ffffff;
    }

    .dark-showcase .section-desc {
      color: #9fb7bc;
    }

    .dark-card {
      background: #0f272c;
      border: 1px solid rgba(255, 255, 255, 0.09);
      border-radius: var(--radius-md);
      padding: 1.875rem;
    }

    /* 流程图步进 */
    .process-timeline {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 1.25rem;
      position: relative;
    }

    .process-step {
      background: #ffffff;
      border: 1px solid var(--color-border-subtle);
      border-radius: var(--radius-md);
      padding: 1.5rem;
      position: relative;
      border-top: 3px solid var(--color-primary);
    }

    .step-number {
      font-size: 1.5rem;
      font-weight: 800;
      color: var(--color-accent-gold);
      margin-bottom: 0.75rem;
      font-family: monospace;
    }

    /* 数据指标条 */
    .metrics-bar {
      background-color: var(--color-primary);
      color: #ffffff;
      padding: 3.5rem 0;
    }

    .metrics-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 2rem;
      text-align: center;
    }

    .metric-value {
      font-size: 2.75rem;
      font-weight: 800;
      font-family: monospace;
      color: #ffffff;
      line-height: 1.1;
      margin-bottom: 0.5rem;
    }

    .metric-value span {
      color: var(--color-accent-gold);
      font-size: 1.75rem;
    }

    .metric-label {
      font-size: 0.9375rem;
      color: #B2D1D6;
      font-weight: 500;
    }

    /* FAQ 手风琴 */
    .faq-container {
      max-width: 860px;
      margin: 0 auto;
    }

    .faq-item {
      background: #ffffff;
      border: 1px solid var(--color-border-subtle);
      border-radius: var(--radius-md);
      margin-bottom: 1rem;
      overflow: hidden;
    }

    .faq-toggle {
      width: 100%;
      text-align: left;
      padding: 1.25rem 1.5rem;
      background: none;
      border: none;
      font-size: 1.0625rem;
      font-weight: 600;
      color: var(--color-primary);
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
    }

    .faq-toggle:hover {
      background-color: #fcfdfe;
    }

    .faq-indicator {
      font-size: 1.25rem;
      color: var(--color-accent-gold);
      transition: transform 0.2s ease;
    }

    .faq-answer {
      display: none;
      padding: 0 1.5rem 1.25rem 1.5rem;
      color: var(--color-text-muted);
      font-size: 0.9375rem;
      line-height: 1.75;
      border-top: 1px solid #f0f4f5;
    }

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

    .faq-item.open .faq-indicator {
      transform: rotate(45deg);
    }

    /* 表单组件 */
    .form-group {
      margin-bottom: 1.25rem;
    }

    .form-label {
      display: block;
      font-size: 0.875rem;
      font-weight: 600;
      color: #334447;
      margin-bottom: 0.4rem;
    }

    .form-control {
      width: 100%;
      padding: 0.75rem 1rem;
      border: 1px solid var(--color-border-subtle);
      border-radius: var(--radius-sm);
      background-color: #ffffff;
      color: var(--color-text-main);
      outline: none;
      transition: var(--transition-base);
    }

    .form-control:focus {
      border-color: var(--color-accent-blue);
      box-shadow: 0 0 0 3px rgba(29, 99, 136, 0.15);
    }

    /* 页脚 */
    .site-footer {
      background-color: var(--color-primary-dark);
      color: #92A6AA;
      font-size: 0.875rem;
      padding-top: 4.5rem;
      padding-bottom: 2rem;
      border-top: 1px solid rgba(255,255,255,0.08);
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1.5fr;
      gap: 3rem;
      margin-bottom: 3.5rem;
    }

    .footer-col h4 {
      color: #ffffff;
      font-size: 1rem;
      font-weight: 700;
      margin-bottom: 1.25rem;
      position: relative;
      padding-bottom: 0.5rem;
    }

    .footer-col h4::after {
      content: "";
      position: absolute;
      left: 0;
      bottom: 0;
      width: 24px;
      height: 2px;
      background: var(--color-accent-gold);
    }

    .footer-links {
      list-style: none;
    }

    .footer-links li {
      margin-bottom: 0.7rem;
    }

    .footer-links a:hover {
      color: #ffffff;
    }

    .footer-bottom {
      border-top: 1px solid rgba(255, 255, 255, 0.08);
      padding-top: 2rem;
      display: flex;
      justify-content: space-between;
      align-items: center;
      flex-wrap: wrap;
      gap: 1rem;
      font-size: 0.8125rem;
    }

    /* 响应式调整 */
    @media (max-width: 1024px) {
      .process-timeline {
        grid-template-columns: repeat(2, 1fr);
      }
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
    }

    @media (max-width: 768px) {
      .split-layout {
        grid-template-columns: 1fr;
      }
      .metrics-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .nav-links, .nav-action {
        display: none;
      }
      .mobile-menu-btn {
        display: block;
      }
      .nav-links.mobile-open {
        display: flex;
        flex-direction: column;
        position: absolute;
        top: 70px;
        left: 0;
        right: 0;
        background: #ffffff;
        padding: 1.5rem;
        border-bottom: 1px solid var(--color-border-subtle);
        box-shadow: 0 10px 15px rgba(0,0,0,0.1);
      }
      .hero-title {
        font-size: 2rem;
      }
      .footer-grid {
        grid-template-columns: 1fr;
      }
    }

    @media (max-width: 520px) {
      .process-timeline {
        grid-template-columns: 1fr;
      }
      .metrics-grid {
        grid-template-columns: 1fr;
      }
      .card-grid {
        grid-template-columns: 1fr;
      }
    }