/* roulang page: index */
:root {
      --primary: #4E6EF2;
      --primary-dark: #3A5AD9;
      --primary-light: #EEF1FD;
      --success: #00B578;
      --warning: #FF9F0A;
      --error: #FA5151;
      --text-primary: #1F2329;
      --text-secondary: #86909C;
      --bg-light: #F5F6FA;
      --bg-white: #FFFFFF;
      --border: #E5E8EC;
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-input: 12px;
      --radius-img: 24px;
      --shadow-sm: 0 2px 12px rgba(0,0,0,0.04);
      --shadow-md: 0 4px 20px rgba(0,0,0,0.08);
      --shadow-img: 0 8px 30px rgba(0,0,0,0.06);
      --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
      --spacing-section: 80px;
    }

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

    body {
      font-family: var(--font-sans);
      color: var(--text-primary);
      background-color: var(--bg-white);
      line-height: 1.6;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }

    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }

    h1, h2, h3 {
      color: var(--text-primary);
    }

    h1 {
      font-size: 36px;
      font-weight: 700;
      line-height: 1.3;
    }

    h2 {
      font-size: 28px;
      font-weight: 600;
      line-height: 1.4;
      margin-bottom: 24px;
    }

    h3 {
      font-size: 20px;
      font-weight: 500;
      line-height: 1.5;
    }

    a {
      color: var(--text-primary);
      text-decoration: none;
      transition: color 0.2s ease;
    }

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

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

    button, .btn {
      cursor: pointer;
      font-family: var(--font-sans);
      border: none;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      transition: all 0.2s ease;
    }

    /* 导航 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 64px;
      background: rgba(255,255,255,0.95);
      backdrop-filter: blur(8px);
      border-bottom: 1px solid var(--border);
      z-index: 100;
      transition: background 0.2s ease;
    }

    .site-header.scrolled {
      background: #FFFFFF;
    }

    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 100%;
    }

    .logo {
      font-size: 22px;
      font-weight: 700;
      color: var(--text-primary);
      letter-spacing: 1px;
    }

    .logo i {
      color: var(--primary);
      margin-right: 6px;
    }

    .nav-links {
      display: flex;
      gap: 32px;
    }

    .nav-links a {
      font-size: 16px;
      font-weight: 500;
      position: relative;
      padding: 8px 0;
    }

    .nav-links a.active,
    .nav-links a:hover {
      color: var(--primary);
    }

    .nav-links a.active::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 100%;
      height: 2px;
      background: var(--primary);
      border-radius: 1px;
    }

    .btn-primary {
      background: var(--primary);
      color: white;
      border-radius: var(--radius-btn);
      padding: 8px 20px;
      font-weight: 600;
      font-size: 16px;
    }

    .btn-primary:hover {
      background: var(--primary-dark);
    }

    .hamburger {
      display: none;
      background: none;
      border: none;
      width: 32px;
      height: 32px;
      flex-direction: column;
      justify-content: center;
      gap: 6px;
    }

    .hamburger span {
      display: block;
      width: 24px;
      height: 2px;
      background: var(--text-primary);
      border-radius: 2px;
      transition: 0.2s;
    }

    /* 移动端抽屉 */
    .mobile-drawer {
      position: fixed;
      top: 0;
      left: -100%;
      width: 80vw;
      height: 100vh;
      background: white;
      box-shadow: 2px 0 20px rgba(0,0,0,0.1);
      z-index: 200;
      padding: 24px;
      display: flex;
      flex-direction: column;
      gap: 24px;
      transition: left 0.25s ease-out;
    }

    .mobile-drawer.open {
      left: 0;
    }

    .drawer-overlay {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background: rgba(0,0,0,0.4);
      z-index: 150;
      display: none;
    }

    .drawer-overlay.show {
      display: block;
    }

    .mobile-drawer a {
      font-size: 18px;
      font-weight: 500;
      padding: 12px 0;
      border-bottom: 1px solid var(--border);
    }

    /* Hero */
    .hero {
      padding: 140px 0 80px;
      background: var(--bg-light);
    }

    .hero-grid {
      display: flex;
      align-items: center;
      gap: 60px;
    }

    .hero-left {
      flex: 0 0 58%;
    }

    .hero-right {
      flex: 1;
      position: relative;
    }

    .hero-img {
      width: 100%;
      border-radius: var(--radius-img);
      box-shadow: var(--shadow-img);
      animation: float 4s ease-in-out infinite;
      object-fit: cover;
    }

    @keyframes float {
      0%, 100% { transform: translateY(0); }
      50% { transform: translateY(-8px); }
    }

    .hero-subtitle {
      color: var(--text-secondary);
      font-size: 16px;
      margin: 20px 0 28px;
      line-height: 1.6;
    }

    .btn-group {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }

    .btn-secondary {
      background: var(--bg-light);
      color: var(--text-primary);
      border-radius: var(--radius-btn);
      padding: 10px 24px;
      font-weight: 600;
    }

    .btn-secondary:hover {
      background: #E5E8EC;
    }

    .trust-badges {
      display: flex;
      gap: 32px;
      margin-top: 32px;
    }

    .badge-item {
      text-align: center;
    }

    .badge-number {
      font-size: 24px;
      font-weight: 700;
      color: var(--primary);
    }

    .badge-label {
      font-size: 14px;
      color: var(--text-secondary);
    }

    /* 亮点网格 */
    .features {
      padding: var(--spacing-section) 0;
    }

    .features-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .feature-card {
      background: white;
      border-radius: var(--radius-card);
      padding: 24px;
      box-shadow: var(--shadow-sm);
      transition: all 0.2s ease;
    }

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

    .feature-icon {
      width: 48px;
      height: 48px;
      background: var(--primary-light);
      border-radius: 12px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--primary);
      font-size: 24px;
      margin-bottom: 16px;
    }

    .feature-card h3 {
      font-size: 18px;
      font-weight: 600;
      margin-bottom: 8px;
    }

    .feature-card p {
      color: var(--text-secondary);
      font-size: 14px;
      line-height: 1.5;
    }

    /* 案例瀑布 */
    .cases {
      padding: var(--spacing-section) 0;
      background: var(--bg-white);
    }

    .case-grid {
      columns: 2;
      column-gap: 24px;
      margin-top: 16px;
    }

    .case-card {
      break-inside: avoid;
      margin-bottom: 24px;
      border-radius: var(--radius-card);
      overflow: hidden;
      position: relative;
      box-shadow: var(--shadow-sm);
      transition: box-shadow 0.25s;
    }

    .case-card:hover {
      box-shadow: var(--shadow-md);
    }

    .case-img-wrap {
      position: relative;
      overflow: hidden;
      height: auto;
    }

    .case-img {
      width: 100%;
      height: auto;
      display: block;
      object-fit: cover;
      transition: transform 0.25s;
    }

    .case-card:hover .case-img {
      transform: scale(1.02);
    }

    .case-overlay {
      position: absolute;
      bottom: 0;
      left: 0;
      right: 0;
      padding: 24px;
      background: linear-gradient(to top, rgba(0,0,0,0.6), transparent);
      color: white;
    }

    .case-title {
      font-size: 18px;
      font-weight: 700;
    }

    .case-tag {
      background: rgba(78,110,242,0.15);
      color: white;
      font-size: 12px;
      padding: 4px 10px;
      border-radius: 20px;
      display: inline-block;
      margin-top: 8px;
    }

    /* 方案对比 */
    .pricing {
      padding: var(--spacing-section) 0;
      background: var(--bg-light);
    }

    .pricing-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .plan-card {
      background: white;
      border-radius: var(--radius-card);
      border: 1px solid var(--border);
      padding: 24px;
      position: relative;
      transition: box-shadow 0.2s, border-color 0.2s;
    }

    .plan-card:hover {
      box-shadow: var(--shadow-md);
      border-color: var(--primary);
    }

    .plan-recommended {
      border: 2px solid var(--primary);
    }

    .plan-badge {
      position: absolute;
      top: -10px;
      right: 20px;
      background: var(--success);
      color: white;
      font-size: 12px;
      padding: 4px 12px;
      border-radius: 20px;
      font-weight: 600;
    }

    .plan-name {
      font-size: 20px;
      font-weight: 600;
    }

    .plan-price {
      font-size: 28px;
      font-weight: 700;
      color: var(--primary);
      margin: 16px 0;
    }

    .plan-features {
      list-style: none;
      margin: 20px 0;
    }

    .plan-features li {
      font-size: 14px;
      margin-bottom: 12px;
      display: flex;
      align-items: center;
      gap: 8px;
      color: var(--text-secondary);
    }

    .fa-check-circle {
      color: var(--success);
    }

    .fa-times-circle {
      color: #ccc;
    }

    /* FAQ */
    .faq {
      padding: var(--spacing-section) 0;
    }

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

    .faq-question {
      width: 100%;
      background: none;
      padding: 16px 0;
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-size: 16px;
      font-weight: 500;
      color: var(--text-primary);
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.15s ease-out;
      background: var(--bg-light);
      border-radius: 8px;
      margin-bottom: 8px;
    }

    .faq-answer p {
      padding: 16px;
      font-size: 14px;
      color: var(--text-secondary);
      line-height: 1.6;
    }

    .faq-item.active .faq-answer {
      max-height: 200px;
    }

    /* CTA */
    .cta-section {
      background: var(--primary);
      padding: var(--spacing-section) 0;
      color: white;
    }

    .cta-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 40px;
      align-items: center;
    }

    .cta-form input, .cta-form textarea {
      width: 100%;
      padding: 12px 16px;
      border-radius: var(--radius-input);
      border: none;
      font-size: 16px;
      margin-bottom: 16px;
      transition: box-shadow 0.2s;
    }

    .cta-form input:focus, .cta-form textarea:focus {
      outline: none;
      box-shadow: 0 0 0 3px rgba(255,255,255,0.4);
    }

    .btn-white {
      background: white;
      color: var(--primary);
      font-weight: 600;
      padding: 12px 32px;
      border-radius: var(--radius-btn);
    }

    .btn-white:hover {
      background: transparent;
      color: white;
      border: 1px solid white;
    }

    .contact-info i {
      margin-right: 8px;
      width: 20px;
    }

    /* 页脚 */
    .footer {
      background: #1F2329;
      color: var(--text-secondary);
      padding: 60px 0 20px;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 30px;
    }

    .footer-logo {
      color: white;
      font-size: 20px;
      font-weight: 700;
    }

    .footer a {
      color: var(--text-secondary);
      font-size: 14px;
    }

    .footer a:hover {
      color: var(--primary);
    }

    .copyright {
      border-top: 1px solid #333;
      margin-top: 40px;
      padding-top: 20px;
      font-size: 12px;
      text-align: center;
    }

    @media (max-width: 1023px) {
      .hamburger {
        display: flex;
      }
      .nav-links, .header .btn-primary {
        display: none;
      }
      .hero-grid {
        flex-direction: column;
      }
      .pricing-grid {
        grid-template-columns: 1fr;
      }
      .features-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .case-grid {
        columns: 1;
      }
    }

    @media (max-width: 767px) {
      .container {
        padding: 0 20px;
      }
      h1 {
        font-size: 32px;
      }
      .features-grid {
        grid-template-columns: 1fr;
      }
      .cta-grid {
        grid-template-columns: 1fr;
      }
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
      .trust-badges {
        flex-wrap: wrap;
      }
    }