/* roulang page: index */
:root {
      --primary: #0F4C5C;
      --primary-light: rgba(15, 76, 92, 0.08);
      --secondary: #F49E4C;
      --secondary-hover: #E8832A;
      --bg: #FAFAF8;
      --surface: #FFFFFF;
      --surface-alt: #F4F6F5;
      --text: #1A1A1A;
      --text-muted: #5C6B6F;
      --border: rgba(15, 76, 92, 0.08);
      --shadow-sm: 0 2px 12px rgba(15, 76, 92, 0.06);
      --shadow-md: 0 8px 24px rgba(15, 76, 92, 0.12);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-input: 6px;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Inter", system-ui, -apple-system, sans-serif;
      --transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
      --max-width: 1200px;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-sans);
      background: var(--bg);
      color: var(--text);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }
    .container {
      width: 100%;
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
    }
    img {
      max-width: 100%;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition);
    }
    button {
      font-family: inherit;
      cursor: pointer;
      border: none;
      background: none;
      transition: var(--transition);
    }
    h1, h2, h3 {
      font-weight: 600;
    }
    h1 {
      font-size: 42px;
      letter-spacing: -0.5px;
      line-height: 1.2;
    }
    h2 {
      font-size: 32px;
      letter-spacing: -0.3px;
      margin-bottom: 16px;
    }
    h3 {
      font-size: 20px;
      margin-bottom: 8px;
    }
    .section {
      padding: 100px 0;
    }
    .text-muted {
      color: var(--text-muted);
    }

    /* 导航 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 64px;
      background: rgba(255,255,255,0.85);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      z-index: 1000;
      border-bottom: 1px solid transparent;
      transition: var(--transition);
    }
    .header.scrolled {
      border-bottom: 1px solid var(--border);
      box-shadow: var(--shadow-sm);
    }
    .nav {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 64px;
    }
    .logo {
      font-size: 24px;
      font-weight: 700;
      color: var(--primary);
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .logo i {
      font-size: 28px;
      color: var(--secondary);
    }
    .nav-links {
      display: flex;
      gap: 32px;
      align-items: center;
    }
    .nav-links a {
      font-size: 15px;
      font-weight: 500;
      color: var(--text);
      position: relative;
      padding: 4px 0;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--secondary);
      transition: width 0.2s ease;
    }
    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 100%;
    }
    .menu-toggle {
      display: none;
      font-size: 24px;
      color: var(--primary);
    }
    .mobile-menu {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: rgba(250,250,248,0.96);
      backdrop-filter: blur(16px);
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 32px;
      transform: translateY(-100%);
      transition: 0.35s ease;
      z-index: 999;
    }
    .mobile-menu.open {
      transform: translateY(0);
    }
    .mobile-menu a {
      font-size: 22px;
      font-weight: 600;
      color: var(--primary);
    }
    .mobile-menu .close-menu {
      position: absolute;
      top: 24px;
      right: 24px;
      font-size: 30px;
    }

    /* 按钮 */
    .btn {
      display: inline-block;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 15px;
      letter-spacing: 0.3px;
      text-align: center;
    }
    .btn-primary {
      background: var(--secondary);
      color: #fff;
    }
    .btn-primary:hover {
      background: var(--secondary-hover);
      transform: scale(1.03);
    }
    .btn-outline {
      background: transparent;
      border: 1.5px solid var(--primary);
      color: var(--primary);
    }
    .btn-outline:hover {
      background: var(--primary-light);
      transform: scale(1.03);
    }
    .btn-text {
      color: var(--secondary);
      font-weight: 500;
    }
    .btn-text i {
      margin-left: 4px;
      font-size: 14px;
    }

    /* Hero */
    .hero {
      min-height: 90vh;
      display: flex;
      align-items: center;
      background: radial-gradient(at 70% 30%, rgba(244,158,76,0.06), transparent 60%);
      padding-top: 64px;
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 48px;
      align-items: center;
    }
    .hero-content h1 {
      margin-bottom: 20px;
    }
    .hero-content .subtitle {
      font-size: 18px;
      color: var(--text-muted);
      margin-bottom: 32px;
      max-width: 480px;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .hero-image img {
      border-radius: 24px;
      box-shadow: var(--shadow-md);
      width: 100%;
    }

    /* 功能卡片 */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      margin-top: 40px;
    }
    .feature-card {
      background: var(--surface);
      border: 1px solid var(--border);
      border-radius: var(--radius-card);
      padding: 32px 24px;
      transition: var(--transition);
      box-shadow: var(--shadow-sm);
    }
    .feature-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-md);
    }
    .feature-icon {
      font-size: 40px;
      color: var(--primary);
      margin-bottom: 20px;
      transition: 0.2s;
    }
    .feature-card:hover .feature-icon {
      color: var(--secondary);
      transform: rotate(2deg);
    }
    .feature-card h3 {
      margin-bottom: 10px;
    }

    /* 场景 */
    .scenario-row {
      display: flex;
      align-items: center;
      gap: 60px;
      margin-bottom: 80px;
    }
    .scenario-row.reverse {
      flex-direction: row-reverse;
    }
    .scenario-img {
      flex: 1 1 55%;
      border-radius: 16px;
      overflow: hidden;
      box-shadow: var(--shadow-sm);
    }
    .scenario-img img {
      width: 100%;
      height: auto;
      display: block;
    }
    .scenario-text {
      flex: 1 1 45%;
    }
    .tag {
      display: inline-block;
      background: var(--primary-light);
      color: var(--primary);
      font-size: 13px;
      font-weight: 600;
      padding: 4px 12px;
      border-radius: 20px;
      margin-bottom: 16px;
    }

    /* 案例 */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 24px;
      margin-top: 40px;
    }
    .case-card {
      background: var(--surface-alt);
      border-radius: var(--radius-card);
      padding: 28px;
      transition: var(--transition);
    }
    .case-number {
      font-size: 32px;
      font-weight: 700;
      color: var(--secondary);
      margin-bottom: 12px;
    }
    .case-quote {
      font-style: italic;
      margin-bottom: 16px;
      color: var(--text);
    }

    /* 价格 */
    .pricing-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      margin-top: 40px;
    }
    .pricing-card {
      background: var(--surface);
      border: 1px solid var(--border);
      border-radius: var(--radius-card);
      padding: 36px 28px;
      text-align: center;
      transition: var(--transition);
      position: relative;
    }
    .pricing-card.featured {
      border: 2px solid var(--primary);
      transform: scale(1.02);
      box-shadow: var(--shadow-md);
    }
    .badge {
      background: var(--secondary);
      color: #fff;
      font-size: 13px;
      padding: 4px 14px;
      border-radius: 20px;
      position: absolute;
      top: -12px;
      left: 50%;
      transform: translateX(-50%);
      font-weight: 600;
    }
    .price {
      font-size: 38px;
      font-weight: 700;
      color: var(--primary);
      margin: 16px 0;
    }
    .feature-list {
      list-style: none;
      text-align: left;
      margin: 24px 0;
    }
    .feature-list li {
      margin-bottom: 12px;
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .feature-list i {
      color: var(--secondary);
    }

    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 40px auto 0;
    }
    .faq-item {
      border-bottom: 1px solid var(--border);
      padding: 16px 0;
    }
    .faq-question {
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      font-size: 18px;
      cursor: pointer;
      padding: 8px 0;
      transition: 0.3s;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      color: var(--text-muted);
    }
    .faq-item.open .faq-answer {
      max-height: 200px;
      padding-bottom: 12px;
    }
    .faq-item.open .faq-question {
      color: var(--primary);
    }

    /* CTA */
    .cta-band {
      background: var(--primary);
      color: #fff;
      text-align: center;
      padding: 80px 24px;
      position: relative;
      overflow: hidden;
    }
    .cta-band::before {
      content: "";
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background-image: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 200 100" opacity="0.05"><path d="M20 30 Q 60 10 100 30 T 180 30" stroke="white" fill="none" stroke-width="1.5"/><circle cx="50" cy="40" r="3" fill="white"/><circle cx="130" cy="50" r="4" fill="white"/></svg>');
      background-size: cover;
    }
    .cta-band h2 {
      color: #fff;
    }

    /* 页脚 */
    .footer {
      background: #1A1A1A;
      color: #B0B8BC;
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 32px;
    }
    .footer a:hover {
      color: var(--secondary);
    }
    .copyright {
      border-top: 1px solid #2A2A2A;
      margin-top: 40px;
      padding-top: 20px;
      text-align: center;
      font-size: 14px;
    }

    @media (max-width: 1024px) {
      .hero-grid, .features-grid, .pricing-grid {
        grid-template-columns: 1fr;
      }
      .scenario-row, .scenario-row.reverse {
        flex-direction: column;
      }
      .cases-grid {
        grid-template-columns: 1fr;
      }
    }
    @media (max-width: 768px) {
      h1 { font-size: 32px; }
      h2 { font-size: 26px; }
      .section { padding: 60px 0; }
      .nav-links { display: none; }
      .menu-toggle { display: block; }
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
    }