/* roulang page: index */
:root {
      --primary: #1B3A5C;
      --primary-hover: #142b45;
      --accent: #C4933A;
      --accent-light: rgba(196, 147, 58, 0.1);
      --bg: #FAF9F6;
      --card-bg: #FFFFFF;
      --footer-bg: #F0EFEA;
      --text: #1E1E1E;
      --text-secondary: #4A4A4A;
      --text-muted: #6B6B6B;
      --border: #EAE8E3;
      --radius-card: 8px;
      --radius-btn: 6px;
      --radius-tag: 4px;
      --shadow-sm: 0 2px 12px rgba(0,0,0,0.04), 0 1px 2px rgba(0,0,0,0.05);
      --shadow-hover: 0 8px 24px rgba(0,0,0,0.08);
      --transition: all 0.25s ease;
      --font-heading: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      --font-body: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
      --max-width: 1200px;
    }

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

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

    h1, h2, h3, h4 {
      font-family: var(--font-heading);
      font-weight: 600;
      line-height: 1.4;
      margin-bottom: 0.5rem;
    }

    h1 {
      font-size: 36px;
      font-weight: 700;
      letter-spacing: -0.5px;
      margin-bottom: 1rem;
    }

    h2 {
      font-size: 28px;
      margin-bottom: 2rem;
      position: relative;
      display: inline-block;
    }

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

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

    a:hover {
      color: var(--primary-hover);
      text-decoration: underline;
    }

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

    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 1.5rem;
    }

    section {
      padding: 80px 0;
    }

    .bg-light {
      background-color: #F4F6F9;
    }

    .btn {
      display: inline-block;
      font-weight: 600;
      font-size: 15px;
      letter-spacing: 0.5px;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      border: 2px solid transparent;
      cursor: pointer;
      transition: var(--transition);
      text-align: center;
      background: transparent;
      line-height: 1.2;
    }

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

    .btn-primary:hover {
      background-color: var(--primary-hover);
      border-color: var(--primary-hover);
      transform: translateY(-1px);
      box-shadow: var(--shadow-hover);
      color: white;
      text-decoration: none;
    }

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

    .btn-outline:hover {
      background-color: var(--accent-light);
      border-color: var(--accent);
      color: var(--accent);
      text-decoration: none;
    }

    .btn-white {
      background: transparent;
      border-color: white;
      color: white;
    }

    .btn-white:hover {
      background: white;
      color: var(--primary);
      border-color: white;
      text-decoration: none;
    }

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

    .btn-gold:hover {
      background: #b0812f;
      border-color: #b0812f;
      color: white;
      text-decoration: none;
    }

    /* 导航 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: rgba(255,255,255,0.92);
      backdrop-filter: blur(10px);
      box-shadow: 0 1px 8px rgba(0,0,0,0.04);
      z-index: 100;
      padding: 0.75rem 0;
    }

    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 1.5rem;
    }

    .logo {
      font-family: var(--font-heading);
      font-weight: 700;
      font-size: 24px;
      color: var(--primary);
      display: flex;
      align-items: center;
      gap: 8px;
      text-decoration: none;
      white-space: nowrap;
    }

    .logo i {
      font-size: 32px;
      color: var(--accent);
    }

    .nav-left, .nav-right {
      display: flex;
      align-items: center;
      gap: 2rem;
    }

    .nav-link {
      font-size: 15px;
      font-weight: 500;
      color: var(--text-secondary);
      text-decoration: none;
      position: relative;
      padding: 4px 0;
      transition: var(--transition);
    }

    .nav-link::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 50%;
      width: 0;
      height: 2px;
      background: var(--primary);
      transition: width 0.2s ease, left 0.2s ease;
    }

    .nav-link:hover {
      color: var(--primary);
      text-decoration: none;
    }

    .nav-link:hover::after {
      width: 100%;
      left: 0;
    }

    .hamburger {
      display: none;
      background: none;
      border: none;
      font-size: 24px;
      color: var(--primary);
      cursor: pointer;
    }

    .mobile-menu {
      display: none;
      position: fixed;
      top: 70px;
      left: 0;
      width: 100%;
      background: white;
      box-shadow: 0 8px 20px rgba(0,0,0,0.08);
      padding: 1.5rem;
      flex-direction: column;
      gap: 1.2rem;
      z-index: 99;
    }

    .mobile-menu a {
      font-size: 16px;
      color: var(--text);
      text-decoration: none;
      padding: 8px 0;
      border-bottom: 1px solid var(--border);
    }

    /* Hero */
    .hero {
      padding: 120px 0 80px;
      min-height: 85vh;
      display: flex;
      align-items: center;
    }

    .hero-grid {
      display: flex;
      align-items: center;
      gap: 3rem;
    }

    .hero-left {
      flex: 0 0 60%;
    }

    .hero-right {
      flex: 0 0 40%;
      position: relative;
    }

    .hero-image {
      border-radius: 12px;
      overflow: hidden;
      box-shadow: var(--shadow-hover);
    }

    .hero-data-card {
      position: absolute;
      bottom: -20px;
      left: -20px;
      background: white;
      padding: 16px 24px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      font-weight: 600;
      color: var(--primary);
      display: flex;
      gap: 12px;
      align-items: center;
      border-left: 4px solid var(--accent);
    }

    .hero-subtitle {
      font-size: 18px;
      color: var(--text-secondary);
      margin-bottom: 2rem;
    }

    /* 卡片网格 */
    .card-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .feature-card {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      padding: 28px;
      border: 1px solid var(--border);
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
    }

    .feature-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }

    .feature-icon {
      font-size: 36px;
      color: var(--accent);
      margin-bottom: 1rem;
    }

    /* 案例瀑布流 */
    .masonry {
      columns: 3;
      column-gap: 32px;
    }

    .case-card {
      break-inside: avoid;
      margin-bottom: 32px;
      background: var(--card-bg);
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
    }

    .case-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }

    .case-img {
      width: 100%;
      aspect-ratio: 3/2;
      object-fit: cover;
    }

    .case-content {
      padding: 20px;
    }

    .case-tag {
      font-size: 13px;
      color: var(--text-muted);
      margin-top: 8px;
    }

    /* 方案对比 */
    .compare-row {
      display: flex;
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
    }

    .compare-col {
      flex: 1;
      padding: 40px;
      background: #F4F6F9;
    }

    .compare-col:last-child {
      background: #FAF9F6;
      border-left: 1px solid var(--border);
    }

    .compare-list {
      list-style: none;
      margin: 1.5rem 0;
    }

    .compare-list li {
      margin-bottom: 0.75rem;
      display: flex;
      align-items: center;
      gap: 8px;
    }

    .compare-list i {
      color: var(--accent);
    }

    /* FAQ */
    .accordion {
      max-width: 800px;
      margin: 0 auto;
    }

    .accordion-item {
      border-bottom: 1px solid var(--border);
    }

    .accordion-title {
      font-size: 20px;
      font-weight: 600;
      padding: 20px 0;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      color: var(--text);
    }

    .accordion-content {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      background: #F9F9F7;
      border-radius: 0 0 8px 8px;
    }

    .accordion-content p {
      padding: 16px 24px;
      color: var(--text-secondary);
    }

    .accordion-item.active .accordion-content {
      max-height: 300px;
    }

    /* CTA */
    .cta-full {
      background: var(--primary);
      color: white;
      text-align: center;
    }

    .cta-buttons {
      display: flex;
      justify-content: center;
      gap: 16px;
      flex-wrap: wrap;
    }

    /* 页脚 */
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 2rem;
    }

    .footer-links a {
      display: block;
      color: var(--text-secondary);
      margin-bottom: 0.5rem;
    }

    .copyright {
      border-top: 1px solid var(--border);
      margin-top: 2rem;
      padding-top: 1.5rem;
      color: var(--text-muted);
      font-size: 14px;
    }

    @media (max-width: 1024px) {
      .nav-left, .nav-right {
        display: none;
      }
      .hamburger {
        display: block;
      }
      .hero-grid {
        flex-direction: column;
      }
      .hero-left, .hero-right {
        flex: auto;
      }
      .card-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .masonry {
        columns: 2;
      }
      .compare-row {
        flex-direction: column;
      }
    }

    @media (max-width: 640px) {
      h1 {
        font-size: 30px;
      }
      .card-grid {
        grid-template-columns: 1fr;
      }
      .masonry {
        columns: 1;
      }
      .footer-grid {
        grid-template-columns: 1fr;
      }
      .hero-data-card {
        position: static;
        margin-top: 1rem;
      }
      .nav-container {
        justify-content: space-between;
      }
    }