/* roulang page: index */
:root {
      --primary: #0A1628;
      --accent: #00E5A0;
      --warm-accent: #FF6B3D;
      --bg-white: #FFFFFF;
      --bg-light: #F4F6FA;
      --bg-dark-start: #0A1628;
      --bg-dark-end: #162033;
      --text-primary: #0A1628;
      --text-body: #2D3748;
      --text-muted: #718096;
      --text-on-dark: #FFFFFF;
      --text-dark-muted: #B0BEC5;
      --border-light: #E2E8F0;
      --border-dark: #2D3748;
      --shadow-card: 0 4px 20px rgba(10,22,40,0.08);
      --shadow-nav: 0 1px 0 rgba(0,0,0,0.04);
      --shadow-nav-scroll: 0 2px 8px rgba(0,0,0,0.06);
      --radius-btn: 8px;
      --radius-card: 12px;
      --radius-dashboard: 16px;
      --radius-faq: 8px;
      --space-section: 80px;
      --space-mobile-section: 48px;
      --container-max: 1200px;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Inter", system-ui, sans-serif;
      --transition-smooth: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
    }

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

    body {
      font-family: var(--font-sans);
      background-color: var(--bg-white);
      color: var(--text-body);
      line-height: 1.7;
      -webkit-font-smoothing: antialiased;
      -moz-osx-font-smoothing: grayscale;
      scroll-behavior: smooth;
    }

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

    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition-smooth);
    }

    button, .btn {
      cursor: pointer;
      font-family: inherit;
      transition: var(--transition-smooth);
      display: inline-flex;
      align-items: center;
      justify-content: center;
      border: none;
      background: none;
      font-weight: 600;
      font-size: 0.95rem;
      border-radius: var(--radius-btn);
    }

    .container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding-left: 24px;
      padding-right: 24px;
    }

    @media (max-width: 768px) {
      .container {
        padding-left: 16px;
        padding-right: 16px;
      }
    }

    /* 导航 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 64px;
      background: var(--bg-white);
      border-bottom: 1px solid transparent;
      z-index: 50;
      transition: box-shadow 0.3s ease, border-color 0.3s ease;
      display: flex;
      align-items: center;
    }

    .site-header.scrolled {
      box-shadow: var(--shadow-nav-scroll);
      border-bottom-color: rgba(0,0,0,0.02);
    }

    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
    }

    .logo {
      font-weight: 700;
      font-size: 1.4rem;
      letter-spacing: -0.2px;
      display: flex;
      align-items: baseline;
      gap: 2px;
      color: var(--primary);
    }
    .logo .accent {
      color: var(--accent);
      margin-left: 1px;
    }

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

    .nav-links a {
      font-size: 0.95rem;
      font-weight: 500;
      color: #4A5568;
      padding: 6px 0;
      border-bottom: 2px solid transparent;
      transition: var(--transition-smooth);
    }

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

    .header-cta {
      background: var(--accent);
      color: white;
      padding: 10px 22px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 0.9rem;
      box-shadow: 0 2px 6px rgba(0,229,160,0.2);
    }
    .header-cta:hover {
      background: #00c98c;
      transform: scale(1.02);
    }

    .burger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      padding: 8px;
      z-index: 100;
    }
    .burger span {
      width: 22px;
      height: 2px;
      background: var(--primary);
      transition: 0.2s;
      border-radius: 2px;
    }
    .burger.active span:nth-child(1) { transform: rotate(45deg) translate(5px,5px); }
    .burger.active span:nth-child(2) { opacity: 0; }
    .burger.active span:nth-child(3) { transform: rotate(-45deg) translate(5px,-5px); }

    @media (max-width: 768px) {
      .nav-links, .header-cta.desktop-only {
        display: none;
      }
      .burger {
        display: flex;
      }
      .header-cta.mobile-cta {
        display: block;
        background: var(--accent);
        color: white;
        padding: 10px 20px;
        border-radius: var(--radius-btn);
        margin-top: 24px;
        text-align: center;
        font-weight: 600;
      }
    }

    .mobile-menu {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: rgba(255,255,255,0.98);
      backdrop-filter: blur(12px);
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 28px;
      z-index: 45;
      opacity: 0;
      visibility: hidden;
      transition: opacity 0.25s ease, visibility 0.25s;
    }
    .mobile-menu.open {
      opacity: 1;
      visibility: visible;
    }
    .mobile-menu a {
      font-size: 1.4rem;
      font-weight: 600;
      color: var(--primary);
      padding: 8px 24px;
      border-radius: 40px;
    }
    .mobile-menu a:hover {
      background: rgba(0,229,160,0.08);
    }

    /* 区块通用 */
    section {
      padding: var(--space-section) 0;
    }
    @media (max-width: 768px) {
      section {
        padding: var(--space-mobile-section) 0;
      }
    }

    .section-title {
      font-size: 2rem;
      font-weight: 600;
      color: var(--text-primary);
      margin-bottom: 16px;
      letter-spacing: -0.3px;
    }
    @media (max-width: 768px) {
      .section-title { font-size: 1.65rem; }
    }

    /* Hero */
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 48px;
      align-items: center;
      min-height: 85vh;
      padding-top: 64px;
    }
    .hero-left h1 {
      font-size: 2.8rem;
      font-weight: 700;
      line-height: 1.2;
      color: var(--primary);
      margin-bottom: 20px;
    }
    .hero-left .sub {
      font-size: 1.15rem;
      color: var(--text-body);
      margin-bottom: 28px;
      max-width: 90%;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
      margin-bottom: 32px;
    }
    .btn-primary {
      background: var(--accent);
      color: white;
      padding: 12px 28px;
      box-shadow: 0 4px 14px rgba(0,229,160,0.25);
    }
    .btn-primary:hover { background: #00c98c; transform: scale(1.03); }
    .btn-outline {
      border: 1px solid var(--border-light);
      background: white;
      color: var(--primary);
      padding: 12px 28px;
    }
    .btn-outline:hover { border-color: var(--accent); background: #f0fdf7; }

    .mini-stats {
      display: flex;
      gap: 32px;
      margin-top: 12px;
    }
    .stat-item .stat-number {
      font-size: 2rem;
      font-weight: 700;
      color: var(--accent);
      font-feature-settings: "tnum";
      letter-spacing: -0.5px;
    }
    .stat-item .stat-label {
      font-size: 0.85rem;
      color: var(--text-muted);
    }

    .hero-right {
      position: relative;
      display: flex;
      justify-content: center;
    }
    .hero-img-wrapper {
      background: radial-gradient(circle at 50% 50%, rgba(0,229,160,0.06) 0%, transparent 70%);
      border-radius: 32px;
      padding: 16px;
      animation: float 6s ease-in-out infinite;
    }
    @keyframes float {
      0%,100%{ transform: translateY(0); }
      50%{ transform: translateY(-10px); }
    }

    @media (max-width: 768px) {
      .hero-grid { grid-template-columns: 1fr; gap: 32px; text-align: center; }
      .hero-left h1 { font-size: 2rem; }
      .hero-left .sub { max-width: 100%; }
      .mini-stats { justify-content: center; }
      .hero-right { order: -1; }
    }

    /* 数据看板 */
    .dashboard-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      margin-top: 32px;
    }
    .dash-card {
      background: rgba(244,246,250,0.9);
      backdrop-filter: blur(4px);
      border: 1px solid var(--border-light);
      border-radius: var(--radius-dashboard);
      padding: 28px 24px;
      transition: var(--transition-smooth);
    }
    .dash-number {
      font-size: 2.8rem;
      font-weight: 700;
      color: var(--primary);
      font-feature-settings: "tnum";
    }
    .trend-line {
      height: 40px;
      width: 100%;
      margin: 16px 0 8px;
      background: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 30"><polyline points="2,22 20,18 40,14 60,10 80,6 98,2" stroke="%2300E5A0" stroke-width="2.5" fill="none" stroke-linecap="round"/></svg>') no-repeat center;
      background-size: contain;
    }
    .dash-label {
      font-weight: 500;
      color: var(--text-muted);
      font-size: 0.9rem;
    }

    @media (max-width: 768px) {
      .dashboard-grid { grid-template-columns: 1fr; }
    }

    /* 服务矩阵 非对称网格 */
    .services-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      margin-top: 32px;
    }
    .service-card {
      background: white;
      border: 1px solid var(--border-light);
      border-radius: var(--radius-card);
      padding: 28px 24px;
      transition: var(--transition-smooth);
      display: flex;
      flex-direction: column;
    }
    .service-card.featured {
      grid-column: span 2;
      background: #fafcff;
    }
    .service-card:hover {
      border-color: var(--accent);
      transform: translateY(-4px);
      box-shadow: var(--shadow-card);
    }
    .service-icon {
      font-size: 1.8rem;
      margin-bottom: 18px;
      color: var(--accent);
    }
    .service-card h3 {
      font-size: 1.35rem;
      font-weight: 600;
      margin-bottom: 8px;
      color: var(--primary);
    }
    .service-desc {
      color: var(--text-muted);
      margin-bottom: 18px;
      flex:1;
    }
    .service-link {
      font-weight: 600;
      color: var(--accent);
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .service-link:hover { gap: 12px; }

    @media (max-width: 768px) {
      .services-grid { grid-template-columns: 1fr; }
      .service-card.featured { grid-column: span 1; }
    }

    /* 对比 */
    .compare-panel {
      display: grid;
      grid-template-columns: 1fr auto 1fr;
      gap: 0;
      margin-top: 40px;
      align-items: stretch;
    }
    .compare-left, .compare-right {
      padding: 32px;
      border-radius: 16px;
    }
    .compare-left {
      background: #F4F6FA;
      color: #4A5568;
    }
    .compare-right {
      background: white;
      border: 1px solid var(--accent);
      box-shadow: 0 0 0 5px rgba(0,229,160,0.06);
    }
    .compare-item {
      display: flex;
      align-items: center;
      gap: 12px;
      margin-bottom: 18px;
    }
    .vs-divider {
      display: flex;
      align-items: center;
      justify-content: center;
      padding: 0 12px;
    }
    .vs-circle {
      background: white;
      border-radius: 50%;
      width: 48px;
      height: 48px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      box-shadow: 0 4px 12px rgba(0,0,0,0.06);
      color: var(--primary);
    }

    @media (max-width: 768px) {
      .compare-panel { grid-template-columns: 1fr; }
      .vs-divider { margin: 16px 0; }
    }

    /* FAQ */
    .faq-list {
      max-width: 720px;
      margin: 32px auto 0;
    }
    .faq-item {
      background: #F4F6FA;
      border-radius: var(--radius-faq);
      margin-bottom: 12px;
      border: 1px solid transparent;
      transition: var(--transition-smooth);
    }
    .faq-item.active {
      background: white;
      border-color: var(--accent);
    }
    .faq-question {
      padding: 16px 20px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      color: var(--primary);
      cursor: pointer;
      user-select: none;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      padding: 0 20px;
      color: #4A5568;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-bottom: 16px;
    }

    /* CTA 深色 */
    .cta-dark {
      background: linear-gradient(135deg, var(--bg-dark-start), var(--bg-dark-end));
      background-image: linear-gradient(135deg, #0A1628, #162033), url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" width="4" height="4"><circle cx="2" cy="2" r="0.6" fill="rgba(255,255,255,0.06)"/></svg>');
      text-align: center;
      padding: 80px 0;
    }
    .cta-dark h2 {
      color: white;
      font-size: 2.2rem;
    }
    .cta-buttons {
      display: flex;
      gap: 16px;
      justify-content: center;
      margin: 28px 0 16px;
    }
    .btn-white {
      background: white;
      color: var(--primary);
      padding: 12px 32px;
    }
    .btn-ghost {
      border: 1px solid rgba(255,255,255,0.5);
      color: white;
      padding: 12px 32px;
    }

    footer {
      background: #1A1D22;
      color: #B0BEC5;
      padding: 48px 0 24px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 32px;
    }
    @media (max-width: 768px) {
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }