/* roulang page: index */
:root {
      --primary: #FF6B35;
      --primary-light: #FF8C42;
      --primary-soft: rgba(255, 107, 53, 0.12);
      --primary-gradient: linear-gradient(135deg, #FF6B35 0%, #FF8C42 50%, #FFB347 100%);
      --secondary: #1A1D23;
      --bg: #F8F7F4;
      --surface: #FFFFFF;
      --text: #1A1D23;
      --text-secondary: #5A5E66;
      --border: #E0DED9;
      --success: #00C897;
      --warning: #FF6B35;
      --shadow-sm: 0 2px 12px rgba(26, 29, 35, 0.06);
      --shadow-md: 0 8px 30px rgba(26, 29, 35, 0.12);
      --radius-lg: 16px;
      --radius-md: 12px;
      --radius-sm: 8px;
      --transition: 0.25s cubic-bezier(0.2, 0.0, 0.0, 1);
      --nav-height: 64px;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: 'Noto Sans SC', 'Inter', system-ui, -apple-system, sans-serif;
      background-color: var(--bg);
      color: var(--text);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition);
    }
    button {
      font-family: inherit;
      cursor: pointer;
      border: none;
      background: none;
    }
    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }
    /* 导航 */
    .nav {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--nav-height);
      background: rgba(255, 255, 255, 0.95);
      backdrop-filter: blur(10px);
      z-index: 100;
      display: flex;
      align-items: center;
      transition: box-shadow var(--transition);
    }
    .nav.scrolled {
      box-shadow: 0 1px 12px rgba(0,0,0,0.08);
    }
    .nav .container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }
    .logo {
      display: flex;
      align-items: center;
      gap: 8px;
      font-weight: 800;
      font-size: 22px;
      color: var(--secondary);
      letter-spacing: -0.3px;
    }
    .logo-icon {
      width: 32px;
      height: 32px;
      background: var(--primary-gradient);
      border-radius: 8px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: white;
      font-size: 18px;
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
      font-weight: 500;
      font-size: 15px;
      color: var(--text-secondary);
    }
    .nav-links a:hover, .nav-links a.active {
      color: var(--primary);
    }
    .btn-nav {
      background: var(--primary-gradient);
      color: white;
      padding: 10px 24px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      font-size: 14px;
      transition: var(--transition);
      box-shadow: 0 4px 14px rgba(255, 107, 53, 0.3);
    }
    .btn-nav:hover {
      transform: translateY(-2px);
      box-shadow: 0 8px 20px rgba(255, 107, 53, 0.4);
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      padding: 4px;
    }
    .hamburger span {
      width: 24px;
      height: 2px;
      background: var(--secondary);
      transition: var(--transition);
    }
    /* 移动端菜单 */
    .mobile-menu {
      position: fixed;
      top: var(--nav-height);
      left: 0;
      width: 100%;
      background: white;
      padding: 24px;
      box-shadow: var(--shadow-md);
      display: none;
      flex-direction: column;
      gap: 20px;
      z-index: 99;
      border-top: 1px solid var(--border);
    }
    .mobile-menu a {
      font-size: 18px;
      font-weight: 500;
      padding: 8px 0;
      border-bottom: 1px solid var(--border);
    }
    /* 通用板块 */
    section {
      padding: 100px 0;
    }
    .section-title {
      font-size: 36px;
      font-weight: 700;
      line-height: 1.3;
      margin-bottom: 16px;
      color: var(--secondary);
    }
    .section-sub {
      font-size: 18px;
      color: var(--text-secondary);
      margin-bottom: 48px;
      max-width: 600px;
    }
    .text-center {
      text-align: center;
    }
    .mx-auto {
      margin-left: auto;
      margin-right: auto;
    }
    /* 按钮系统 */
    .btn-primary {
      background: var(--primary-gradient);
      color: white;
      padding: 14px 32px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      font-size: 16px;
      box-shadow: 0 4px 14px rgba(255, 107, 53, 0.35);
      transition: var(--transition);
      display: inline-block;
      text-align: center;
    }
    .btn-primary:hover {
      transform: translateY(-2px);
      box-shadow: 0 10px 24px rgba(255, 107, 53, 0.45);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
      padding: 14px 32px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      font-size: 16px;
      transition: var(--transition);
      display: inline-block;
    }
    .btn-outline:hover {
      background: rgba(255,107,53,0.08);
    }
    .btn-light {
      border: 2px solid white;
      color: white;
      padding: 14px 32px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      background: transparent;
      transition: var(--transition);
    }
    .btn-light:hover {
      background: white;
      color: var(--primary);
    }
    /* Hero */
    .hero {
      padding: 160px 0 100px;
      background: radial-gradient(circle at 80% 20%, rgba(255,107,53,0.08) 0%, var(--bg) 70%);
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 60px;
      align-items: center;
    }
    .hero h1 {
      font-size: 48px;
      font-weight: 800;
      line-height: 1.2;
      color: var(--secondary);
      margin-bottom: 20px;
    }
    .hero-sub {
      font-size: 18px;
      color: var(--text-secondary);
      margin-bottom: 32px;
    }
    .badge-group {
      display: flex;
      gap: 16px;
      margin-bottom: 32px;
      flex-wrap: wrap;
    }
    .badge {
      background: var(--primary-soft);
      color: var(--primary);
      padding: 8px 20px;
      border-radius: 40px;
      font-weight: 700;
      font-size: 15px;
    }
    .hero-image {
      background: var(--surface);
      border-radius: 24px;
      padding: 12px;
      box-shadow: 0 20px 40px rgba(255,107,53,0.18);
      border: 1px solid rgba(255,107,53,0.2);
    }
    .hero-image img {
      border-radius: 16px;
      width: 100%;
    }
    /* 数据看板 */
    .dashboard-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
    }
    .stat-card {
      background: var(--surface);
      border-radius: var(--radius-lg);
      padding: 28px;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      text-align: center;
    }
    .stat-icon {
      font-size: 28px;
      margin-bottom: 12px;
    }
    .stat-label {
      font-size: 14px;
      color: var(--text-secondary);
      margin-bottom: 8px;
    }
    .stat-number {
      font-size: 32px;
      font-weight: 800;
      font-feature-settings: "tnum";
      color: var(--secondary);
    }
    .stat-trend {
      font-size: 14px;
      margin-top: 8px;
      font-weight: 600;
    }
    .trend-up { color: var(--success); }
    /* 服务卡片 */
    .services-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .service-card {
      background: var(--surface);
      border-radius: var(--radius-lg);
      padding: 32px;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
    }
    .service-card:hover {
      transform: translateY(-8px);
      box-shadow: var(--shadow-md);
    }
    .service-icon {
      width: 64px;
      height: 64px;
      background: var(--primary-gradient);
      border-radius: 16px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: white;
      font-size: 28px;
      margin-bottom: 20px;
      transition: transform 0.3s;
    }
    .service-card:hover .service-icon {
      transform: scale(1.05);
    }
    .service-card h3 {
      font-size: 20px;
      font-weight: 600;
      margin-bottom: 8px;
    }
    .service-desc {
      font-size: 14px;
      color: var(--text-secondary);
      margin-bottom: 16px;
      line-height: 1.6;
    }
    .data-tag {
      font-weight: 700;
      color: var(--primary);
      font-size: 15px;
    }
    /* 流程对比 */
    .process-row {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 48px;
      align-items: start;
    }
    .steps {
      display: flex;
      flex-direction: column;
      gap: 24px;
    }
    .step-item {
      display: flex;
      gap: 16px;
    }
    .step-num {
      font-size: 48px;
      font-weight: 800;
      color: rgba(255,107,53,0.2);
      line-height: 1;
    }
    .comparison {
      background: var(--surface);
      border-radius: var(--radius-lg);
      padding: 28px;
      box-shadow: var(--shadow-sm);
    }
    .compare-row {
      display: flex;
      justify-content: space-between;
      margin-bottom: 16px;
    }
    .vs-badge {
      background: var(--primary);
      color: white;
      border-radius: 50%;
      width: 40px;
      height: 40px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 800;
      margin: 12px auto;
    }
    .old { color: #d32f2f; background: #ffebee; padding: 4px 12px; border-radius: 20px; }
    .new { color: #2e7d32; background: #e8f5e9; padding: 4px 12px; border-radius: 20px; }
    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      border-bottom: 1px solid var(--border);
    }
    .faq-question {
      width: 100%;
      display: flex;
      justify-content: space-between;
      align-items: center;
      padding: 20px 0;
      font-weight: 600;
      font-size: 18px;
      text-align: left;
      background: transparent;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      color: var(--text-secondary);
    }
    .faq-answer.open {
      max-height: 200px;
      padding-bottom: 16px;
    }
    /* CTA */
    .cta-section {
      background: linear-gradient(135deg, #1A1D23 0%, #0D0F12 100%);
      color: white;
      padding: 100px 0;
      text-align: center;
    }
    /* 页脚 */
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
      padding: 60px 0 40px;
    }
    .footer-bottom {
      border-top: 1px solid var(--border);
      padding: 24px 0;
      text-align: center;
      color: var(--text-secondary);
      font-size: 14px;
    }
    @media (max-width: 1024px) {
      .hero-grid { grid-template-columns: 1fr; }
      .dashboard-grid { grid-template-columns: repeat(2, 1fr); }
      .services-grid { grid-template-columns: 1fr 1fr; }
      .section-title { font-size: 32px; }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .hero h1 { font-size: 32px; }
      .dashboard-grid { grid-template-columns: 1fr 1fr; }
      .services-grid { grid-template-columns: 1fr; }
      .process-row { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }