/* roulang page: index */
:root {
      --primary-dark: #2D2D2D;
      --accent-copper: #C47E5A;
      --accent-copper-hover: #B06E4A;
      --bg-warm: #FAF8F6;
      --bg-light: #F0EDEA;
      --text-dark: #1A1A1A;
      --text-mid: #6B6B6B;
      --text-light: #999;
      --deep-green: #3D6B5A;
      --border-light: rgba(0,0,0,0.04);
      --border-medium: #E8E5E2;
      --radius-lg: 12px;
      --radius-md: 8px;
      --radius-sm: 6px;
      --shadow-sm: 0 2px 12px rgba(0,0,0,0.04);
      --shadow-hover: 0 8px 30px rgba(0,0,0,0.08);
      --font-sans: -apple-system, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
    }
    * {
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--bg-warm);
      color: var(--text-dark);
      margin: 0;
      line-height: 1.7;
      -webkit-font-smoothing: antialiased;
      scroll-behavior: smooth;
    }
    h1, h2, h3, h4 {
      font-weight: 600;
      color: var(--primary-dark);
    }
    h1 {
      font-size: 42px;
      font-weight: 700;
      line-height: 1.2;
      letter-spacing: -0.5px;
    }
    h2 {
      font-size: 32px;
      line-height: 1.3;
    }
    h3 {
      font-size: 22px;
      line-height: 1.4;
    }
    h4 {
      font-size: 18px;
      line-height: 1.5;
    }
    p {
      color: var(--text-mid);
      font-size: 16px;
      margin-bottom: 1.2em;
    }
    .text-small {
      font-size: 14px;
      color: var(--text-mid);
    }
    a {
      color: var(--accent-copper);
      text-decoration: none;
      transition: all 0.25s ease;
    }
    a:hover {
      color: var(--accent-copper-hover);
      text-decoration: underline;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    .container-custom {
      max-width: 1200px;
      margin: 0 auto;
      padding-left: 20px;
      padding-right: 20px;
    }
    section {
      padding: 100px 0;
    }
    @media (max-width: 992px) {
      section {
        padding: 60px 0;
      }
    }
    @media (max-width: 768px) {
      section {
        padding: 40px 0;
      }
    }
    /* 导航栏 */
    .navbar-custom {
      height: 72px;
      background: rgba(255,255,255,0.92);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      border-bottom: 1px solid rgba(0,0,0,0.05);
      display: flex;
      align-items: center;
      position: sticky;
      top: 0;
      z-index: 1000;
    }
    .logo {
      font-size: 24px;
      font-weight: 700;
      color: var(--accent-copper);
      letter-spacing: 1px;
      display: flex;
      align-items: center;
      gap: 8px;
      text-decoration: none;
    }
    .logo i {
      font-size: 28px;
      color: var(--accent-copper);
    }
    .nav-search {
      width: 280px;
      background: #F5F2EF;
      border-radius: 24px;
      border: 1px solid transparent;
      padding: 8px 18px;
      display: flex;
      align-items: center;
      transition: all 0.2s ease;
      box-shadow: inset 0 1px 4px rgba(0,0,0,0.02);
    }
    .nav-search input {
      background: transparent;
      border: none;
      outline: none;
      width: 100%;
      font-size: 15px;
      color: var(--primary-dark);
    }
    .nav-search input::placeholder {
      color: #9A9A9A;
      font-weight: 400;
    }
    .nav-search i {
      color: #6B6B6B;
      margin-right: 8px;
    }
    .nav-search:focus-within {
      border-color: var(--accent-copper);
      box-shadow: 0 0 0 3px rgba(196,126,90,0.15);
      background: white;
    }
    .nav-links a {
      font-size: 15px;
      font-weight: 500;
      color: #4A4A4A;
      margin-left: 28px;
      text-decoration: none;
      position: relative;
    }
    .nav-links a:hover, .nav-links a.active {
      color: var(--accent-copper);
    }
    .nav-links a.active::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 100%;
      height: 2px;
      background: var(--accent-copper);
    }
    .mobile-toggle {
      display: none;
      background: none;
      border: none;
      font-size: 24px;
      color: var(--primary-dark);
    }
    @media (max-width: 992px) {
      .nav-search {
        width: 200px;
      }
    }
    @media (max-width: 768px) {
      .nav-links, .nav-search {
        display: none;
      }
      .mobile-toggle {
        display: block;
      }
      .mobile-menu {
        position: fixed;
        top: 72px;
        left: 0;
        width: 100%;
        background: rgba(255,255,255,0.98);
        backdrop-filter: blur(12px);
        padding: 24px;
        flex-direction: column;
        gap: 16px;
        display: none;
        z-index: 999;
      }
      .mobile-menu.active {
        display: flex;
      }
      .mobile-search {
        width: 100%;
        background: #F5F2EF;
        border-radius: 24px;
        padding: 10px 20px;
        display: flex;
        margin-bottom: 10px;
      }
      .mobile-search input {
        background: transparent;
        border: none;
        outline: none;
        width: 100%;
      }
    }
    /* 按钮 */
    .btn-primary-custom {
      background: var(--accent-copper);
      color: white;
      border-radius: var(--radius-sm);
      padding: 14px 32px;
      font-weight: 600;
      font-size: 16px;
      letter-spacing: 1px;
      border: none;
      transition: all 0.25s ease;
      display: inline-block;
      text-decoration: none;
    }
    .btn-primary-custom:hover {
      background: var(--accent-copper-hover);
      transform: translateY(-2px);
      box-shadow: 0 12px 24px rgba(196,126,90,0.2);
      color: white;
      text-decoration: none;
    }
    .btn-outline-custom {
      background: transparent;
      border: 1px solid var(--accent-copper);
      color: var(--accent-copper);
      border-radius: var(--radius-sm);
      padding: 14px 32px;
      font-weight: 600;
      font-size: 16px;
      transition: all 0.25s ease;
      display: inline-block;
      text-decoration: none;
    }
    .btn-outline-custom:hover {
      background: var(--accent-copper);
      color: white;
      transform: translateY(-2px);
    }
    .text-link {
      color: var(--accent-copper);
      font-weight: 500;
      display: inline-flex;
      align-items: center;
      gap: 6px;
      transition: gap 0.2s;
    }
    .text-link i {
      font-size: 12px;
    }
    .text-link:hover {
      gap: 10px;
      text-decoration: none;
    }
    /* 卡片 */
    .service-card {
      background: white;
      border-radius: var(--radius-lg);
      padding: 32px;
      box-shadow: var(--shadow-sm);
      border: 1px solid var(--border-light);
      transition: all 0.3s ease;
    }
    .service-card:hover {
      box-shadow: var(--shadow-hover);
      transform: translateY(-4px);
    }
    .middle-card {
      margin-top: -12px;
      box-shadow: 0 12px 28px rgba(0,0,0,0.06);
    }
    .icon-circle {
      width: 64px;
      height: 64px;
      background: #F5F0EC;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--accent-copper);
      font-size: 28px;
      margin-bottom: 20px;
    }
    .case-card {
      background: white;
      border-radius: var(--radius-lg);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: 0.3s;
    }
    .case-card:hover {
      box-shadow: var(--shadow-hover);
    }
    .case-img {
      position: relative;
      overflow: hidden;
      aspect-ratio: 16 / 10;
    }
    .case-img img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      transition: transform 0.4s ease;
    }
    .case-card:hover .case-img img {
      transform: scale(1.03);
    }
    .case-overlay {
      position: absolute;
      bottom: 0;
      left: 0;
      width: 100%;
      height: 40%;
      background: linear-gradient(to top, rgba(196,126,90,0.5), transparent);
      opacity: 0;
      transition: 0.3s;
    }
    .case-card:hover .case-overlay {
      opacity: 1;
    }
    .tag {
      background: #F0EDEA;
      color: var(--primary-dark);
      font-size: 12px;
      padding: 4px 12px;
      border-radius: 20px;
      display: inline-block;
    }
    /* 优势数据 */
    .stat-number {
      font-size: 48px;
      font-weight: 700;
      color: var(--accent-copper);
    }
    /* FAQ */
    .accordion-custom .accordion-item {
      border: none;
      border-bottom: 1px solid var(--border-medium);
    }
    .accordion-button {
      font-weight: 600;
      font-size: 18px;
      color: var(--primary-dark);
      background: transparent;
      box-shadow: none;
      padding: 20px 0;
    }
    .accordion-button:not(.collapsed) {
      color: var(--accent-copper);
      background: transparent;
      border-left: 3px solid var(--accent-copper);
      padding-left: 17px;
    }
    .accordion-button:focus {
      box-shadow: none;
    }
    /* CTA */
    .cta-section {
      background: var(--primary-dark);
      color: white;
      border-radius: 0;
    }
    .cta-section h2 {
      color: white;
    }
    .form-control-custom {
      background: rgba(255,255,255,0.08);
      border: 1px solid rgba(255,255,255,0.15);
      color: white;
      border-radius: var(--radius-sm);
      padding: 12px 16px;
    }
    .form-control-custom:focus {
      border-color: var(--accent-copper);
      box-shadow: 0 0 0 3px rgba(196,126,90,0.2);
      background: rgba(255,255,255,0.12);
    }
    /* 页脚 */
    .footer {
      background: #1E1E1E;
      color: #999;
    }
    .footer a {
      color: #999;
    }
    .footer a:hover {
      color: var(--accent-copper);
    }
    /* 动画 */
    .fade-up {
      opacity: 0;
      transform: translateY(20px);
      transition: 0.6s ease;
    }
    .fade-up.visible {
      opacity: 1;
      transform: translateY(0);
    }