/* roulang page: index */
:root {
      --primary: #C8A96E;
      --primary-deep: #B8944F;
      --secondary: #2C2C2C;
      --bg: #FAF7F2;
      --surface: #FFFFFF;
      --accent: #E8923A;
      --text-main: #1E1E1E;
      --text-muted: #6B6B6B;
      --text-white: #FFFFFF;
      --success: #3A7D5A;
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-chip: 20px;
      --shadow-card: 0 2px 12px rgba(0,0,0,0.04);
      --shadow-hover: 0 8px 28px rgba(0,0,0,0.08);
      --font-serif: 'Noto Serif SC', 'Source Han Serif SC', Georgia, serif;
      --font-sans: 'Noto Sans SC', 'Inter', -apple-system, sans-serif;
      --transition: all 0.25s ease;
      --spacing-section: 100px;
    }
    * { box-sizing: border-box; margin: 0; padding: 0; }
    body {
      font-family: var(--font-sans);
      background-color: var(--bg);
      color: var(--text-main);
      line-height: 1.7;
      font-size: 16px;
      scroll-behavior: smooth;
    }
    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }
    h1, h2, h3, h4 {
      font-family: var(--font-serif);
      font-weight: 700;
      color: var(--secondary);
      margin-bottom: 0.75rem;
    }
    h1 { font-size: 42px; line-height: 1.2; letter-spacing: -0.5px; }
    h2 { font-size: 32px; line-height: 1.3; position: relative; display: inline-block; margin-bottom: 2rem; }
    h2::after {
      content: '';
      position: absolute;
      left: 0;
      bottom: -10px;
      width: 40px;
      height: 4px;
      background-color: var(--primary);
      border-radius: 2px;
    }
    h3 { font-size: 22px; line-height: 1.4; font-weight: 600; }
    h4 { font-size: 16px; line-height: 1.5; font-weight: 700; letter-spacing: 0.5px; font-family: var(--font-sans); color: var(--text-white); }
    .section { padding: var(--spacing-section) 0; }
    @media (max-width: 768px) {
      h1 { font-size: 34px; }
      h2 { font-size: 28px; }
      .section { padding: 70px 0; }
    }

    /* 导航栏 */
    .top-bar-custom {
      background: var(--secondary);
      height: 72px;
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 100;
      border-bottom: 1px solid var(--primary);
      display: flex;
      align-items: center;
      padding: 0 28px;
    }
    .logo {
      font-family: var(--font-serif);
      font-weight: 700;
      font-size: 24px;
      color: var(--primary);
      margin-right: auto;
      white-space: nowrap;
      text-decoration: none;
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .logo i { font-size: 20px; color: var(--accent); }
    .nav-links {
      display: flex;
      gap: 8px;
      align-items: center;
      flex-wrap: wrap;
    }
    .nav-chip {
      background: transparent;
      color: var(--text-white);
      padding: 8px 18px;
      border-radius: 20px;
      font-size: 14px;
      font-weight: 500;
      text-decoration: none;
      transition: var(--transition);
      white-space: nowrap;
    }
    .nav-chip:hover { background: rgba(200,169,110,0.2); }
    .nav-chip.active {
      background: var(--primary);
      color: var(--secondary);
      font-weight: 600;
    }
    .nav-cta {
      background: var(--accent);
      color: white;
      padding: 10px 22px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 14px;
      margin-left: 16px;
      text-decoration: none;
      transition: var(--transition);
      white-space: nowrap;
    }
    .nav-cta:hover { background: #d47e2a; color: white; }
    .hamburger {
      display: none;
      font-size: 24px;
      color: var(--text-white);
      cursor: pointer;
      background: none;
      border: none;
    }
    @media (max-width: 1024px) {
      .nav-links { display: none; }
      .hamburger { display: block; margin-left: 20px; }
      .mobile-menu-open .nav-links {
        display: flex;
        flex-direction: column;
        position: absolute;
        top: 72px;
        left: 0;
        width: 100%;
        background: var(--secondary);
        padding: 20px;
        gap: 12px;
        border-top: 1px solid var(--primary);
      }
      .nav-cta { margin-left: 0; }
    }

    /* 按钮系统 */
    .btn-primary {
      background: var(--primary);
      color: white;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      text-decoration: none;
      display: inline-block;
      transition: var(--transition);
      border: none;
      cursor: pointer;
      font-size: 16px;
    }
    .btn-primary:hover {
      background: var(--primary-deep);
      box-shadow: 0 6px 20px rgba(200,169,110,0.4);
      color: white;
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      text-decoration: none;
      transition: var(--transition);
      display: inline-block;
      font-size: 16px;
    }
    .btn-outline:hover {
      background: var(--primary);
      color: white;
    }
    .btn-text {
      color: var(--primary);
      font-weight: 600;
      text-decoration: none;
      position: relative;
      padding-bottom: 2px;
      transition: var(--transition);
    }
    .btn-text::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary);
      transition: width 0.3s;
    }
    .btn-text:hover::after { width: 100%; }
    .btn-white {
      background: white;
      color: var(--primary);
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 700;
      text-decoration: none;
      display: inline-block;
      transition: var(--transition);
    }
    .btn-white:hover { background: #f0f0f0; }

    /* Hero */
    .hero {
      padding-top: 120px;
      display: flex;
      align-items: center;
      gap: 40px;
    }
    .hero-left { flex: 1.1; }
    .hero-right { flex: 0.9; }
    .hero-right img {
      width: 100%;
      border-radius: 16px;
      box-shadow: 0 20px 40px rgba(0,0,0,0.08);
      object-fit: cover;
      height: auto;
    }
    .hero-subtitle {
      font-size: 18px;
      color: var(--text-muted);
      margin: 1rem 0 1.8rem;
      line-height: 1.6;
    }
    @media (max-width: 768px) {
      .hero { flex-direction: column; padding-top: 100px; }
      .hero-right img { height: 280px; object-fit: cover; }
    }

    /* 卡片网格 */
    .card-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 30px;
    }
    .card {
      background: var(--surface);
      border-radius: var(--radius-card);
      padding: 28px;
      box-shadow: var(--shadow-card);
      transition: var(--transition);
      border-bottom: 3px solid transparent;
      position: relative;
    }
    .card:hover {
      box-shadow: var(--shadow-hover);
      transform: translateY(-4px);
      border-bottom-color: var(--primary);
      background: linear-gradient(to bottom, #fff, #fdfaf5);
    }
    .card-icon {
      font-size: 40px;
      color: var(--primary);
      margin-bottom: 16px;
    }
    .card h3 { margin-bottom: 0.5rem; }
    .card p { color: var(--text-muted); margin-bottom: 1rem; }
    @media (max-width: 1024px) { .card-grid { grid-template-columns: repeat(2, 1fr); } }
    @media (max-width: 640px) { .card-grid { grid-template-columns: 1fr; } }

    /* 案例瀑布流 */
    .case-grid {
      columns: 2;
      column-gap: 30px;
      margin-top: 2rem;
    }
    .case-item {
      break-inside: avoid;
      margin-bottom: 30px;
      background: var(--surface);
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-card);
      transition: var(--transition);
    }
    .case-item:hover { box-shadow: var(--shadow-hover); transform: translateY(-3px); }
    .case-img img {
      width: 100%;
      display: block;
      object-fit: cover;
      height: auto;
    }
    .case-content {
      padding: 20px;
    }
    .case-tag {
      display: inline-block;
      border: 1px solid var(--accent);
      color: var(--accent);
      border-radius: 20px;
      padding: 4px 14px;
      font-size: 12px;
      font-weight: 600;
      margin-bottom: 8px;
    }
    @media (max-width: 768px) {
      .case-grid { columns: 1; }
    }

    /* 方案对比 */
    .compare-row {
      display: flex;
      gap: 40px;
      align-items: stretch;
    }
    .compare-col {
      flex: 1;
      background: var(--surface);
      border-radius: var(--radius-card);
      padding: 32px;
      box-shadow: var(--shadow-card);
    }
    .compare-highlight {
      border: 2px solid var(--primary);
      position: relative;
    }
    .compare-badge {
      position: absolute;
      top: -14px;
      right: 24px;
      background: var(--accent);
      color: white;
      padding: 6px 18px;
      border-radius: 20px;
      font-size: 13px;
      font-weight: 700;
    }
    .compare-list { list-style: none; margin: 1.5rem 0; }
    .compare-list li { margin-bottom: 10px; display: flex; align-items: center; gap: 8px; }
    @media (max-width: 768px) {
      .compare-row { flex-direction: column; }
    }

    /* 数据带 */
    .trust-bar {
      background: var(--secondary);
      color: white;
      padding: 50px 0;
      display: flex;
      justify-content: space-around;
      flex-wrap: wrap;
      text-align: center;
    }
    .trust-item .number {
      font-size: 36px;
      font-weight: 700;
      color: var(--accent);
      display: block;
    }
    .trust-item i { color: var(--primary); margin-right: 6px; }

    /* FAQ */
    .accordion-item {
      background: var(--surface);
      border-radius: 8px;
      margin-bottom: 12px;
      box-shadow: 0 1px 4px rgba(0,0,0,0.02);
    }
    .accordion-title {
      font-size: 18px;
      font-weight: 600;
      padding: 18px 24px;
      border-left: 4px solid var(--primary);
      cursor: pointer;
      transition: var(--transition);
    }
    .accordion-title:hover { background: #fef9f0; }
    .accordion-content {
      padding: 0 24px 20px;
      color: var(--text-muted);
      display: none;
    }
    .accordion-item.active .accordion-content { display: block; }

    /* CTA 横幅 */
    .cta-banner {
      background: var(--accent);
      padding: 80px 0;
      text-align: center;
      color: white;
    }
    .cta-banner h2 { color: white; }
    .cta-banner h2::after { background: white; }

    /* 页脚 */
    .footer {
      background: var(--secondary);
      color: #B0B0B0;
      padding: 60px 0 20px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 30px;
    }
    .footer-col h4::after {
      content: '';
      display: block;
      width: 30px;
      height: 3px;
      background: var(--primary);
      margin-top: 8px;
    }
    .footer a { color: #B0B0B0; text-decoration: none; }
    .footer a:hover { color: var(--primary); }
    @media (max-width: 768px) {
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }
    .copyright {
      border-top: 1px solid #444;
      margin-top: 40px;
      padding-top: 20px;
      text-align: center;
      font-size: 14px;
    }