/* roulang page: index */
:root {
      --primary: #4E6EF2;
      --primary-deep: #3A5BE0;
      --green: #00B578;
      --orange: #FF9F0A;
      --red: #FA5151;
      --bg-base: #F5F6FA;
      --white: #FFFFFF;
      --text-primary: #1F2329;
      --text-secondary: #86909C;
      --border-light: #E5E8EF;
      --blue-light-bg: #EEF1FE;
      --glass-bg: rgba(255,255,255,0.72);
      --shadow-card: 0 4px 16px rgba(0,0,0,0.04), 0 2px 6px rgba(0,0,0,0.02);
      --shadow-hover: 0 8px 24px rgba(0,0,0,0.08);
      --radius-card: 16px;
      --radius-mid: 12px;
      --radius-small: 8px;
      --radius-pill: 24px;
      --transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
      --font-sans: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      --max-width: 1200px;
    }

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

    body {
      font-family: var(--font-sans);
      background-color: var(--bg-base);
      color: var(--text-primary);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }

    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 40px;
    }

    /* 导航 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      transition: var(--transition);
      background: rgba(255,255,255,0.85);
      backdrop-filter: blur(20px);
      border-bottom: 1px solid rgba(229,232,239,0.5);
    }
    .navbar.scrolled {
      background: rgba(255,255,255,0.95);
      box-shadow: 0 2px 12px rgba(0,0,0,0.04);
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 40px;
    }
    .logo {
      display: flex;
      align-items: center;
      font-weight: 700;
      font-size: 24px;
      color: var(--text-primary);
      letter-spacing: 0.5px;
    }
    .logo i {
      color: var(--primary);
      margin-right: 8px;
      font-size: 28px;
    }
    .logo span {
      font-size: 12px;
      color: var(--text-secondary);
      margin-left: 8px;
      font-weight: 400;
      letter-spacing: 0;
      align-self: flex-end;
      margin-bottom: 2px;
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
    }
    .nav-links a {
      text-decoration: none;
      color: var(--text-primary);
      font-weight: 500;
      font-size: 16px;
      transition: color 0.2s;
      position: relative;
    }
    .nav-links a:hover {
      color: var(--primary);
    }
    .nav-cta {
      background: var(--primary);
      color: white !important;
      padding: 10px 24px;
      border-radius: var(--radius-small);
      font-weight: 500;
      transition: var(--transition);
      box-shadow: 0 2px 8px rgba(78,110,242,0.3);
    }
    .nav-cta:hover {
      background: var(--primary-deep);
      box-shadow: 0 4px 12px rgba(78,110,242,0.5);
      transform: translateY(-1px);
    }
    .mobile-menu-btn {
      display: none;
      background: none;
      border: none;
      font-size: 28px;
      color: var(--text-primary);
      cursor: pointer;
    }

    /* Hero */
    .hero {
      padding: 140px 0 100px;
      display: flex;
      align-items: center;
      gap: 60px;
      position: relative;
    }
    .hero::before {
      content: "";
      position: absolute;
      top: -80px;
      right: -120px;
      width: 500px;
      height: 500px;
      background: radial-gradient(circle, rgba(78,110,242,0.12) 0%, rgba(78,110,242,0) 70%);
      border-radius: 50%;
      z-index: 0;
    }
    .hero-text {
      flex: 0 0 55%;
      position: relative;
      z-index: 2;
    }
    .hero-text h1 {
      font-size: 52px;
      font-weight: 700;
      line-height: 1.2;
      color: var(--text-primary);
      margin-bottom: 20px;
    }
    .highlight {
      color: var(--primary);
    }
    .hero-text p {
      font-size: 18px;
      color: var(--text-secondary);
      max-width: 500px;
      margin-bottom: 32px;
      line-height: 1.6;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--primary);
      color: white;
      padding: 14px 36px;
      border-radius: var(--radius-small);
      font-weight: 600;
      font-size: 16px;
      text-decoration: none;
      display: inline-flex;
      align-items: center;
      gap: 8px;
      transition: var(--transition);
      border: none;
      cursor: pointer;
      box-shadow: 0 4px 14px rgba(78,110,242,0.3);
    }
    .btn-primary:hover {
      background: var(--primary-deep);
      box-shadow: 0 6px 20px rgba(78,110,242,0.5);
      transform: translateY(-2px);
    }
    .btn-secondary {
      background: transparent;
      border: 1.5px solid var(--primary);
      color: var(--primary);
      padding: 14px 36px;
      border-radius: var(--radius-small);
      font-weight: 600;
      font-size: 16px;
      text-decoration: none;
      transition: var(--transition);
      display: inline-flex;
      align-items: center;
      gap: 8px;
    }
    .btn-secondary:hover {
      background: var(--primary);
      color: white;
    }
    .hero-image {
      flex: 0 0 45%;
      position: relative;
      z-index: 2;
    }
    .hero-image img {
      width: 100%;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
    }
    .floating-card {
      position: absolute;
      bottom: -20px;
      left: -25px;
      background: var(--glass-bg);
      backdrop-filter: blur(18px);
      border: 1px solid rgba(255,255,255,0.5);
      border-radius: var(--radius-mid);
      padding: 16px 24px;
      display: flex;
      gap: 20px;
      box-shadow: var(--shadow-card);
    }
    .floating-stat h4 {
      font-size: 22px;
      color: var(--primary);
      font-weight: 700;
    }
    .floating-stat span {
      font-size: 13px;
      color: var(--text-secondary);
    }

    /* 板块标题 */
    .section-title {
      text-align: center;
      margin-bottom: 60px;
    }
    .section-title h2 {
      font-size: 38px;
      font-weight: 600;
      color: var(--text-primary);
      display: inline-block;
      position: relative;
    }
    .section-title h2::after {
      content: '';
      position: absolute;
      bottom: -12px;
      left: 50%;
      transform: translateX(-50%);
      width: 48px;
      height: 3px;
      background: var(--primary);
      border-radius: 2px;
    }

    /* 核心亮点 */
    .features {
      padding: 80px 0;
    }
    .features-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .feature-card {
      background: var(--white);
      padding: 40px 28px;
      border-radius: var(--radius-mid);
      box-shadow: var(--shadow-card);
      transition: var(--transition);
      text-align: left;
    }
    .feature-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
    }
    .feature-icon {
      background: var(--blue-light-bg);
      width: 56px;
      height: 56px;
      display: flex;
      align-items: center;
      justify-content: center;
      border-radius: 12px;
      margin-bottom: 24px;
      color: var(--primary);
      font-size: 26px;
    }
    .feature-card h3 {
      font-size: 22px;
      font-weight: 600;
      margin-bottom: 10px;
    }
    .feature-card p {
      color: var(--text-secondary);
      font-size: 15px;
    }

    /* 服务瀑布流 */
    .services {
      padding: 80px 0;
    }
    .service-item {
      display: flex;
      align-items: center;
      gap: 60px;
      margin-bottom: 100px;
    }
    .service-item.reverse {
      flex-direction: row-reverse;
    }
    .service-img {
      flex: 0 0 60%;
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-card);
    }
    .service-img img {
      width: 100%;
      display: block;
    }
    .service-content {
      flex: 0 0 40%;
    }
    .service-content h3 {
      font-size: 28px;
      font-weight: 600;
      margin-bottom: 16px;
    }
    .service-content p {
      color: var(--text-secondary);
      margin-bottom: 18px;
    }
    .data-point {
      font-size: 36px;
      font-weight: 700;
      color: var(--primary);
      line-height: 1.2;
    }
    .data-label {
      font-size: 14px;
      color: var(--text-secondary);
    }

    /* 对比表 */
    .pricing {
      padding: 80px 0;
    }
    .pricing-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      align-items: start;
    }
    .plan-card {
      background: var(--white);
      border-radius: var(--radius-mid);
      padding: 36px 28px;
      box-shadow: var(--shadow-card);
      position: relative;
      transition: var(--transition);
      border-top: 4px solid transparent;
    }
    .plan-card.recommended {
      border-top: 4px solid var(--primary);
      box-shadow: var(--shadow-hover);
      transform: scale(1.02);
    }
    .badge {
      background: var(--orange);
      color: white;
      font-size: 12px;
      padding: 4px 12px;
      border-radius: 20px;
      position: absolute;
      top: -12px;
      right: 20px;
      font-weight: 600;
    }
    .plan-card h3 {
      font-size: 24px;
      margin-bottom: 16px;
    }
    .plan-features {
      list-style: none;
      margin: 24px 0;
    }
    .plan-features li {
      margin-bottom: 12px;
      display: flex;
      align-items: center;
      gap: 10px;
      color: var(--text-primary);
    }
    .fa-check { color: var(--green); }
    .fa-times { color: #ccc; }

    /* 数据展示 */
    .stats {
      background: var(--white);
      padding: 70px 0;
      margin: 60px 0;
    }
    .stats-grid {
      display: flex;
      justify-content: space-around;
      text-align: center;
      flex-wrap: wrap;
    }
    .stat-item h3 {
      font-size: 44px;
      font-weight: 700;
      color: var(--primary);
    }

    /* FAQ */
    .faq {
      padding: 80px 0;
    }
    .faq-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 24px;
    }
    .faq-item {
      background: var(--white);
      border-radius: var(--radius-mid);
      padding: 20px 24px;
      box-shadow: var(--shadow-card);
      border-left: 4px solid var(--primary);
      transition: var(--transition);
    }
    .faq-question {
      font-weight: 600;
      font-size: 17px;
      margin-bottom: 8px;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
    }
    .faq-answer {
      color: var(--text-secondary);
      font-size: 15px;
      display: none;
      margin-top: 10px;
    }
    .faq-item.active .faq-answer {
      display: block;
    }

    /* CTA Banner */
    .cta-banner {
      background: linear-gradient(135deg, #2B3A8C 0%, #1F2329 100%);
      border-radius: var(--radius-card);
      padding: 80px 40px;
      text-align: center;
      margin: 80px 0;
      color: white;
    }
    .cta-banner h2 {
      font-size: 38px;
      margin-bottom: 24px;
    }
    .glow-btn {
      background: var(--primary);
      color: white;
      padding: 18px 48px;
      font-size: 18px;
      border-radius: var(--radius-small);
      border: none;
      box-shadow: 0 0 28px rgba(78,110,242,0.7);
      transition: var(--transition);
      cursor: pointer;
      font-weight: 600;
      margin: 24px 0;
    }
    .glow-btn:hover {
      background: var(--primary-deep);
      box-shadow: 0 0 36px rgba(78,110,242,0.9);
    }

    /* 页脚 */
    .footer {
      background: #1F2329;
      color: rgba(255,255,255,0.8);
      padding: 60px 0 30px;
      margin-top: 80px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }
    .footer a {
      color: rgba(255,255,255,0.7);
      text-decoration: none;
    }
    .footer a:hover { color: var(--primary); }
    .copyright {
      border-top: 1px solid rgba(255,255,255,0.1);
      margin-top: 40px;
      padding-top: 20px;
      text-align: center;
      font-size: 14px;
    }

    @media (max-width: 1024px) {
      .container { padding: 0 24px; }
      .hero { flex-direction: column; gap: 40px; }
      .features-grid { grid-template-columns: repeat(2,1fr); }
      .service-item { flex-direction: column; }
      .service-item.reverse { flex-direction: column; }
      .pricing-grid { grid-template-columns: 1fr; max-width: 400px; margin: 0 auto; }
    }

    @media (max-width: 768px) {
      .nav-links { display: none; }
      .mobile-menu-btn { display: block; }
      .features-grid { grid-template-columns: 1fr; }
      .faq-grid { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr; }
      .hero-text h1 { font-size: 36px; }
    }