/* roulang page: index */
/* 设计变量与全局重置 */
    :root {
      --color-primary: #2D4A3E;
      --color-accent: #C8A96E;
      --color-bg: #FAF8F5;
      --color-bg-dark: #1A2A24;
      --color-text: #1A1A1A;
      --color-text-secondary: #5C5C5C;
      --color-text-muted: #8A8A8A;
      --color-border: #E5E0D8;
      --color-white: #FFFFFF;
      --color-success: #4A7C6F;
      --color-highlight: #D4A853;
      
      --font-heading: 'Playfair Display', 'Noto Serif SC', serif;
      --font-body: 'Inter', 'Noto Sans SC', sans-serif;
      
      --radius-sm: 8px;
      --radius-md: 12px;
      --radius-lg: 20px;
      --radius-full: 50%;
      
      --shadow-card: 0 8px 30px rgba(0,0,0,0.06);
      --shadow-nav: 0 1px 0 rgba(0,0,0,0.05);
      
      --spacing-xs: 8px;
      --spacing-sm: 16px;
      --spacing-md: 24px;
      --spacing-lg: 32px;
      --spacing-xl: 48px;
      --spacing-2xl: 64px;
      --spacing-3xl: 80px;
      --spacing-4xl: 120px;
      
      --max-width: 1280px;
      --header-height: 72px;
    }
    
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    
    html {
      scroll-behavior: smooth;
      -webkit-font-smoothing: antialiased;
      -moz-osx-font-smoothing: grayscale;
    }
    
    body {
      font-family: var(--font-body);
      font-size: 16px;
      font-weight: 400;
      line-height: 1.7;
      color: var(--color-text);
      background-color: var(--color-bg);
      overflow-x: hidden;
    }
    
    img {
      display: block;
      max-width: 100%;
      height: auto;
    }
    
    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.25s ease;
    }
    
    button, input, textarea {
      font-family: inherit;
      font-size: inherit;
    }
    
    .container {
      width: 100%;
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 20px;
    }
    
    @media (min-width: 768px) {
      .container {
        padding: 0 40px;
      }
    }
    
    @media (min-width: 1280px) {
      .container {
        padding: 0 80px;
      }
    }
    
    /* 组件基础样式 */
    .btn-primary {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      background: var(--color-accent);
      color: var(--color-white);
      font-weight: 600;
      font-size: 15px;
      letter-spacing: 0.03em;
      padding: 14px 36px;
      border-radius: var(--radius-sm);
      border: none;
      cursor: pointer;
      transition: background 0.35s ease, transform 0.2s ease;
      text-align: center;
    }
    
    .btn-primary:hover {
      background: var(--color-primary);
      transform: translateY(-2px);
    }
    
    .btn-secondary {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      background: transparent;
      color: var(--color-primary);
      font-weight: 500;
      font-size: 15px;
      padding: 13px 35px;
      border-radius: var(--radius-sm);
      border: 1px solid var(--color-primary);
      cursor: pointer;
      transition: all 0.35s ease;
    }
    
    .btn-secondary:hover {
      background: var(--color-primary);
      color: var(--color-white);
    }
    
    .btn-link {
      display: inline-flex;
      align-items: center;
      gap: 6px;
      color: var(--color-accent);
      font-weight: 500;
      font-size: 15px;
      transition: color 0.25s ease, gap 0.25s ease;
    }
    
    .btn-link i {
      transition: transform 0.25s ease;
    }
    
    .btn-link:hover {
      color: var(--color-primary);
    }
    
    .btn-link:hover i {
      transform: translateX(4px);
    }
    
    .badge {
      display: inline-block;
      background: transparent;
      border: 1px solid var(--color-accent);
      color: var(--color-accent);
      font-size: 12px;
      font-weight: 500;
      padding: 4px 14px;
      border-radius: var(--radius-lg);
      letter-spacing: 0.03em;
    }
    
    .card {
      background: var(--color-white);
      border-radius: var(--radius-md);
      border: 1px solid var(--color-border);
      padding: var(--spacing-lg);
      transition: transform 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94), box-shadow 0.3s ease;
    }
    
    .card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-card);
    }
    
    .card-dark {
      background: var(--color-bg-dark);
      color: var(--color-bg);
      border: none;
      padding: 40px;
      border-radius: var(--radius-md);
    }
    
    /* 导航 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--header-height);
      background: rgba(250, 248, 245, 0.92);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      box-shadow: var(--shadow-nav);
      z-index: 1000;
      display: flex;
      align-items: center;
    }
    
    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }
    
    .logo {
      font-family: var(--font-heading);
      font-size: 22px;
      font-weight: 700;
      color: var(--color-primary);
      letter-spacing: 0.02em;
    }
    
    .logo span {
      font-weight: 400;
      font-size: 18px;
    }
    
    .nav-links {
      display: flex;
      align-items: center;
      gap: 48px;
    }
    
    .nav-links a {
      font-size: 15px;
      font-weight: 500;
      color: var(--color-text-secondary);
      letter-spacing: 0.02em;
      position: relative;
      padding: 4px 0;
    }
    
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -2px;
      left: 50%;
      width: 0;
      height: 2px;
      background: var(--color-accent);
      transition: width 0.25s ease, left 0.25s ease;
    }
    
    .nav-links a:hover,
    .nav-links a.active {
      color: var(--color-primary);
    }
    
    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 100%;
      left: 0;
    }
    
    .nav-cta {
      margin-left: 24px;
    }
    
    .hamburger {
      display: none;
      flex-direction: column;
      justify-content: center;
      gap: 6px;
      cursor: pointer;
      background: transparent;
      border: none;
      padding: 8px;
    }
    
    .hamburger span {
      display: block;
      height: 2px;
      background: var(--color-primary);
      transition: all 0.3s ease;
    }
    
    .hamburger span:nth-child(1) { width: 24px; }
    .hamburger span:nth-child(2) { width: 18px; }
    .hamburger span:nth-child(3) { width: 22px; }
    
    /* 移动端菜单 */
    .mobile-menu {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: var(--color-bg-dark);
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 40px;
      z-index: 999;
      opacity: 0;
      visibility: hidden;
      transition: opacity 0.35s ease, visibility 0.35s ease;
    }
    
    .mobile-menu.active {
      opacity: 1;
      visibility: visible;
    }
    
    .mobile-menu a {
      font-size: 24px;
      color: var(--color-bg);
      font-weight: 500;
      letter-spacing: 0.04em;
    }
    
    @media (max-width: 1023px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
    }
    
    /* Hero */
    .hero {
      padding-top: calc(var(--header-height) + 40px);
      padding-bottom: var(--spacing-4xl);
      display: flex;
      align-items: center;
      gap: 60px;
      flex-wrap: wrap;
    }
    
    .hero-content {
      flex: 1 1 400px;
    }
    
    .hero-badge {
      margin-bottom: var(--spacing-md);
      font-size: 13px;
      letter-spacing: 0.08em;
      text-transform: uppercase;
    }
    
    .hero h1 {
      font-family: var(--font-heading);
      font-size: 56px;
      font-weight: 700;
      line-height: 1.1;
      color: var(--color-text);
      margin-bottom: var(--spacing-md);
    }
    
    .hero-subtitle {
      font-size: 18px;
      color: var(--color-text-secondary);
      max-width: 480px;
      margin-bottom: var(--spacing-lg);
    }
    
    .hero-buttons {
      display: flex;
      gap: 24px;
      flex-wrap: wrap;
    }
    
    .hero-image {
      flex: 1 1 500px;
      position: relative;
      border-radius: var(--radius-sm);
      overflow: hidden;
      aspect-ratio: 4 / 3;
      background: #e5e0d8;
    }
    
    .hero-image img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      filter: sepia(0.1) brightness(0.95);
      transition: filter 0.4s;
    }
    
    .hero-image::after {
      content: '';
      position: absolute;
      inset: 0;
      background: rgba(200, 169, 110, 0.08);
      pointer-events: none;
    }
    
    .hero-floating-card {
      position: absolute;
      bottom: 24px;
      right: 24px;
      background: white;
      padding: 16px 24px;
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-card);
      font-size: 14px;
      font-weight: 500;
      color: var(--color-primary);
    }
    
    @media (max-width: 768px) {
      .hero h1 {
        font-size: 36px;
      }
      .hero {
        gap: 40px;
      }
    }
    
    /* 通用板块标题 */
    .section-title {
      font-family: var(--font-heading);
      font-size: 40px;
      font-weight: 600;
      line-height: 1.2;
      margin-bottom: 16px;
    }
    
    .section-subtitle {
      color: var(--color-text-secondary);
      font-size: 18px;
      margin-bottom: 40px;
    }
    
    .accent-line {
      width: 60px;
      height: 2px;
      background: var(--color-accent);
      margin: 16px 0 24px;
    }
    
    .text-center {
      text-align: center;
    }
    
    .mx-auto {
      margin-left: auto;
      margin-right: auto;
    }
    
    /* 优势 */
    .advantages-grid {
      display: grid;
      grid-template-columns: 4fr 4fr 4fr;
      gap: 24px;
    }
    
    .adv-large {
      grid-row: span 2;
    }
    
    .adv-small {
      border-left: 3px solid var(--color-accent);
      padding-left: 24px;
      transition: border-width 0.25s;
    }
    
    .adv-small:hover {
      border-left-width: 6px;
    }
    
    @media (max-width: 1023px) {
      .advantages-grid {
        grid-template-columns: 1fr 1fr;
      }
      .adv-large {
        grid-row: span 1;
        grid-column: span 2;
      }
    }
    
    @media (max-width: 600px) {
      .advantages-grid {
        grid-template-columns: 1fr;
      }
    }
    
    /* 数据块 */
    .data-block {
      background: var(--color-bg-dark);
      padding: var(--spacing-3xl) 0;
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
      text-align: center;
    }
    
    .data-item .number {
      font-family: var(--font-heading);
      font-size: 48px;
      color: var(--color-accent);
      font-weight: 700;
    }
    
    .data-item .label {
      color: var(--color-text-muted);
      font-size: 14px;
      margin-top: 8px;
    }
    
    @media (max-width: 768px) {
      .data-block {
        grid-template-columns: 1fr 1fr;
      }
    }
    
    /* 服务卡片 */
    .services-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 32px;
    }
    
    .service-card img {
      width: 100%;
      aspect-ratio: 4 / 3;
      object-fit: cover;
      border-radius: var(--radius-sm);
      filter: grayscale(0.2) sepia(0.1);
      transition: filter 0.3s;
    }
    
    .service-card:hover img {
      filter: grayscale(0) sepia(0);
    }
    
    @media (max-width: 1023px) {
      .services-grid {
        grid-template-columns: 1fr 1fr;
      }
    }
    
    @media (max-width: 600px) {
      .services-grid {
        grid-template-columns: 1fr;
      }
    }
    
    /* 案例网格 */
    .cases-grid {
      display: grid;
      grid-template-columns: 8fr 4fr;
      gap: 24px;
    }
    
    .case-large img, .case-small img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      border-radius: var(--radius-sm);
    }
    
    .case-small {
      display: flex;
      flex-direction: column;
      gap: 24px;
    }
    
    @media (max-width: 768px) {
      .cases-grid {
        grid-template-columns: 1fr;
      }
    }
    
    /* 流程 */
    .process-steps {
      display: flex;
      justify-content: space-between;
      align-items: center;
    }
    
    .step {
      text-align: center;
      flex: 1;
      position: relative;
    }
    
    .step-number {
      font-family: var(--font-heading);
      font-size: 48px;
      color: #E5E0D8;
      transition: color 0.3s;
    }
    
    .step:hover .step-number {
      color: var(--color-accent);
    }
    
    @media (max-width: 768px) {
      .process-steps {
        flex-direction: column;
        gap: 24px;
      }
    }
    
    /* FAQ */
    .faq-item {
      border-bottom: 1px solid var(--color-border);
      padding: 20px 0;
      cursor: pointer;
    }
    
    .faq-question {
      display: flex;
      align-items: center;
      gap: 12px;
      font-weight: 500;
      font-size: 18px;
    }
    
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      padding-left: 24px;
      color: var(--color-text-secondary);
    }
    
    /* CTA */
    .cta-section {
      background: var(--color-primary);
      padding: var(--spacing-4xl) 0;
      text-align: center;
      color: white;
    }
    
    /* 页脚 */
    .footer {
      background: var(--color-bg-dark);
      color: var(--color-text-muted);
      padding: 60px 0 30px;
    }
    
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }
    
    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
    }
    
    .section-spacing {
      margin-top: var(--spacing-4xl);
      margin-bottom: var(--spacing-4xl);
    }