/* roulang page: index */
:root {
      --primary: #0A66C2;
      --primary-light: #F0F6FF;
      --accent: #FF6B35;
      --accent-hover: #E55A2B;
      --gray-900: #1E293B;
      --gray-700: #334155;
      --gray-600: #475569;
      --gray-500: #64748B;
      --gray-400: #94A3B8;
      --gray-200: #E2E8F0;
      --gray-100: #F1F5F9;
      --gray-50: #F8FAFC;
      --success: #10B981;
      --danger: #EF4444;
      --danger-bg: #FEF2F2;
      --success-bg: #F0FDF4;
      --border-radius-card: 16px;
      --border-radius-btn: 50px;
      --border-radius-input: 8px;
      --shadow-card: 0 4px 20px rgba(0,0,0,0.04);
      --shadow-card-hover: 0 12px 40px rgba(10,102,194,0.12);
      --shadow-nav: 0 1px 3px rgba(0,0,0,0.05);
      --shadow-hero: 0 20px 60px rgba(10,102,194,0.15);
      --font-sans: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      --font-mono: "Inter", "Roboto", sans-serif;
    }

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

    html {
      scroll-behavior: smooth;
    }

    body {
      font-family: var(--font-sans);
      line-height: 1.75;
      color: var(--gray-700);
      background-color: var(--gray-50);
      -webkit-font-smoothing: antialiased;
    }

    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 导航栏 */
    .navbar {
      position: sticky;
      top: 0;
      z-index: 50;
      background: rgba(255,255,255,0.92);
      backdrop-filter: blur(10px);
      box-shadow: var(--shadow-nav);
      border-bottom: 1px solid rgba(226,232,240,0.6);
    }

    .navbar .container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
    }

    .logo a {
      display: flex;
      align-items: center;
      text-decoration: none;
      font-weight: 700;
      font-size: 1.5rem;
      color: var(--primary);
      letter-spacing: -0.5px;
    }

    .logo img {
      height: 36px;
      margin-right: 10px;
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 28px;
      list-style: none;
    }

    .nav-links a {
      font-size: 0.95rem;
      font-weight: 500;
      color: var(--gray-600);
      text-decoration: none;
      padding: 6px 0;
      border-bottom: 2px solid transparent;
      transition: color 0.2s, border-color 0.2s;
    }

    .nav-links a:hover {
      color: var(--primary);
      border-bottom-color: var(--primary);
    }

    .btn-cta {
      background: var(--accent);
      color: #fff;
      font-weight: 600;
      padding: 10px 26px;
      border-radius: var(--border-radius-btn);
      text-decoration: none;
      box-shadow: 0 4px 14px rgba(255,107,53,0.3);
      transition: background 0.2s, box-shadow 0.2s;
      border: none;
      cursor: pointer;
      white-space: nowrap;
    }

    .btn-cta:hover {
      background: var(--accent-hover);
      box-shadow: 0 6px 20px rgba(255,107,53,0.4);
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      background: transparent;
      border: none;
      cursor: pointer;
    }

    .hamburger span {
      display: block;
      width: 24px;
      height: 2.5px;
      background: var(--primary);
      border-radius: 2px;
      transition: 0.2s;
    }

    /* 移动端菜单 */
    .mobile-menu {
      display: none;
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: #fff;
      z-index: 55;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 32px;
    }

    .mobile-menu.active {
      display: flex;
    }

    .mobile-menu a {
      font-size: 1.5rem;
      color: var(--gray-700);
      text-decoration: none;
      font-weight: 500;
    }

    .mobile-menu .close-btn {
      position: absolute;
      top: 24px;
      right: 24px;
      background: none;
      border: none;
      font-size: 2rem;
      cursor: pointer;
      color: var(--gray-700);
    }

    /* HERO */
    .hero {
      min-height: 90vh;
      display: flex;
      align-items: center;
      background: linear-gradient(180deg, #FFFFFF 0%, var(--primary-light) 100%);
    }

    .hero .container {
      display: flex;
      align-items: center;
      gap: 48px;
    }

    .hero-content {
      flex: 1;
    }

    .hero-content h1 {
      font-size: 3.5rem;
      font-weight: 700;
      line-height: 1.2;
      letter-spacing: -0.02em;
      color: var(--gray-900);
      margin-bottom: 20px;
    }

    .hero-content .subtitle {
      font-size: 1.25rem;
      color: var(--gray-500);
      margin-bottom: 32px;
      max-width: 480px;
    }

    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
      margin-bottom: 24px;
    }

    .btn-primary {
      background: var(--accent);
      color: #fff;
      padding: 14px 32px;
      border-radius: var(--border-radius-btn);
      font-weight: 600;
      text-decoration: none;
      box-shadow: 0 4px 14px rgba(255,107,53,0.3);
      transition: background 0.2s, box-shadow 0.2s;
      border: none;
      cursor: pointer;
    }

    .btn-primary:hover {
      background: var(--accent-hover);
      box-shadow: 0 6px 20px rgba(255,107,53,0.4);
    }

    .btn-secondary {
      background: transparent;
      color: var(--primary);
      border: 2px solid var(--primary);
      padding: 14px 32px;
      border-radius: var(--border-radius-btn);
      font-weight: 600;
      text-decoration: none;
      transition: background 0.2s;
    }

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

    .hero-trust {
      font-size: 0.9rem;
      color: var(--gray-500);
      display: flex;
      align-items: center;
      gap: 8px;
    }

    .hero-image {
      flex: 1;
      display: flex;
      justify-content: center;
      transform: perspective(1000px) rotateY(-5deg);
    }

    .hero-image img {
      max-width: 100%;
      border-radius: 24px;
      box-shadow: var(--shadow-hero);
    }

    /* 指标看板 */
    .metrics {
      background: var(--primary-light);
      padding: 40px 0;
    }

    .metrics-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
      text-align: center;
    }

    .metric-item {
      padding: 16px;
    }

    .metric-number {
      font-family: var(--font-mono);
      font-size: 2.5rem;
      font-weight: 800;
      color: var(--primary);
      font-variant-numeric: tabular-nums;
    }

    .metric-label {
      color: var(--gray-600);
      font-size: 1rem;
      margin-top: 4px;
    }

    /* 通用区块标题 */
    .section-title {
      font-size: 2.25rem;
      font-weight: 600;
      color: var(--gray-900);
      text-align: center;
      margin-bottom: 16px;
    }

    .section-subtitle {
      font-size: 1.1rem;
      color: var(--gray-500);
      text-align: center;
      margin-bottom: 48px;
    }

    /* 服务矩阵 */
    .services {
      padding: 80px 0;
    }

    .services-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 32px;
    }

    .service-card {
      background: #fff;
      border-radius: var(--border-radius-card);
      padding: 2rem;
      box-shadow: var(--shadow-card);
      transition: all 0.3s cubic-bezier(0.25,0.8,0.25,1.2);
      display: flex;
      flex-direction: column;
    }

    .service-card:hover {
      transform: translateY(-8px);
      box-shadow: var(--shadow-card-hover);
    }

    .service-icon {
      width: 64px;
      height: 64px;
      background: var(--primary-light);
      border-radius: 12px;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 24px;
      color: var(--primary);
      font-size: 1.8rem;
    }

    .service-card h3 {
      font-size: 1.25rem;
      font-weight: 600;
      margin-bottom: 12px;
      color: var(--gray-900);
    }

    .service-card p {
      color: var(--gray-600);
      margin-bottom: 20px;
      flex: 1;
    }

    .text-link {
      color: var(--primary);
      font-weight: 500;
      text-decoration: none;
      display: inline-flex;
      align-items: center;
      gap: 4px;
      transition: gap 0.2s;
    }

    .text-link:hover {
      gap: 8px;
    }

    /* 对比区块 */
    .comparison {
      padding: 80px 0;
      background: #fff;
    }

    .comparison-wrapper {
      display: grid;
      grid-template-columns: 1fr auto 1fr;
      align-items: center;
      gap: 32px;
    }

    .compare-card {
      padding: 32px;
      border-radius: var(--border-radius-card);
    }

    .compare-card.old {
      background: var(--danger-bg);
    }

    .compare-card.new {
      background: var(--success-bg);
    }

    .compare-card h3 {
      font-size: 1.5rem;
      margin-bottom: 24px;
      display: flex;
      align-items: center;
      gap: 12px;
    }

    .compare-list {
      list-style: none;
    }

    .compare-list li {
      display: flex;
      align-items: flex-start;
      gap: 12px;
      margin-bottom: 16px;
      font-size: 1rem;
    }

    .vs-badge {
      background: var(--primary);
      color: #fff;
      font-weight: 700;
      padding: 12px 24px;
      border-radius: 50px;
      box-shadow: 0 8px 20px rgba(10,102,194,0.2);
      white-space: nowrap;
    }

    .icon-danger {
      color: var(--danger);
      font-weight: bold;
    }

    .icon-success {
      color: var(--success);
      font-weight: bold;
    }

    /* FAQ */
    .faq {
      padding: 80px 0;
      background: var(--gray-50);
    }

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

    .accordion-item {
      border-bottom: 1px solid var(--gray-200);
    }

    .accordion-question {
      width: 100%;
      background: none;
      border: none;
      text-align: left;
      padding: 20px 0;
      font-size: 1.1rem;
      font-weight: 500;
      color: var(--gray-900);
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      transition: color 0.2s;
    }

    .accordion-question:hover {
      color: var(--primary);
    }

    .arrow {
      transition: transform 0.3s;
      font-size: 1.2rem;
    }

    .accordion-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      color: var(--gray-600);
    }

    .accordion-answer p {
      padding-bottom: 20px;
    }

    .accordion-item.active .arrow {
      transform: rotate(180deg);
    }

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

    /* 表单 */
    .contact {
      padding: 80px 0;
      background: #fff;
    }

    .contact-form {
      max-width: 680px;
      margin: 0 auto;
      display: flex;
      flex-direction: column;
      gap: 20px;
    }

    .form-row {
      display: flex;
      gap: 16px;
    }

    .form-group {
      flex: 1;
      display: flex;
      flex-direction: column;
    }

    input, textarea {
      border: 1px solid var(--gray-200);
      border-radius: var(--border-radius-input);
      padding: 12px 16px;
      font-size: 1rem;
      font-family: var(--font-sans);
      transition: border 0.2s, box-shadow 0.2s;
      outline: none;
      background: #fff;
    }

    input:focus, textarea:focus {
      border-color: var(--primary);
      box-shadow: 0 0 0 3px rgba(10,102,194,0.1);
    }

    .btn-submit {
      background: var(--accent);
      color: #fff;
      padding: 16px;
      border-radius: var(--border-radius-btn);
      font-weight: 600;
      font-size: 1.1rem;
      border: none;
      cursor: pointer;
      box-shadow: 0 4px 14px rgba(255,107,53,0.3);
      transition: background 0.2s, box-shadow 0.2s;
    }

    .btn-submit:hover {
      background: var(--accent-hover);
    }

    .privacy-check {
      display: flex;
      align-items: center;
      gap: 10px;
      font-size: 0.9rem;
      color: var(--gray-500);
    }

    .trust-text {
      text-align: center;
      font-size: 0.9rem;
      color: var(--gray-400);
    }

    /* 页脚 */
    .footer {
      background: var(--gray-900);
      color: #CBD5E1;
      padding: 60px 0 30px;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
      margin-bottom: 40px;
    }

    .footer-logo {
      font-size: 1.6rem;
      font-weight: 700;
      color: #fff;
      margin-bottom: 16px;
    }

    .footer h4 {
      color: #fff;
      margin-bottom: 16px;
      font-weight: 600;
    }

    .footer a {
      color: #CBD5E1;
      text-decoration: none;
      display: block;
      margin-bottom: 8px;
      transition: color 0.2s;
    }

    .footer a:hover {
      color: #fff;
    }

    .social-icons {
      display: flex;
      gap: 12px;
    }

    .social-icons a {
      width: 40px;
      height: 40px;
      background: rgba(255,255,255,0.1);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      color: #CBD5E1;
    }

    .footer-bottom {
      border-top: 1px solid rgba(255,255,255,0.1);
      padding-top: 20px;
      text-align: center;
      font-size: 0.9rem;
      color: #94A3B8;
    }

    /* 响应式 */
    @media (max-width: 1024px) {
      .services-grid { grid-template-columns: repeat(2, 1fr); }
      .comparison-wrapper { grid-template-columns: 1fr; }
      .vs-badge { margin: 16px auto; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }

    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .hero .container { flex-direction: column; text-align: center; }
      .hero-content h1 { font-size: 2.5rem; }
      .hero-image { transform: none; margin-top: 24px; }
      .metrics-grid { grid-template-columns: 1fr 1fr; }
      .services-grid { grid-template-columns: 1fr; }
      .form-row { flex-direction: column; }
      .footer-grid { grid-template-columns: 1fr; }
    }