/* roulang page: index */
:root {
      --primary: #4E6EF2;
      --primary-light: rgba(78, 110, 242, 0.12);
      --primary-glow: rgba(78, 110, 242, 0.3);
      --secondary: #00B578;
      --warning: #FF9F0A;
      --danger: #FA5151;
      --bg-light: #F5F6FA;
      --bg-white: #FFFFFF;
      --bg-dark: #1F2329;
      --text-primary: #1F2329;
      --text-secondary: #86909C;
      --text-white: #FFFFFF;
      --border-light: #E5E6EB;
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-pill: 24px;
      --shadow-card: 0 4px 20px rgba(0,0,0,0.04);
      --shadow-card-hover: 0 8px 30px rgba(0,0,0,0.08);
      --shadow-btn-hover: 0 4px 12px;
      --transition: 200ms ease-out;
      --font-stack: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      --header-height: 64px;
      --max-width: 1200px;
      --side-padding: 24px;
    }

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

    html {
      scroll-behavior: smooth;
      scroll-padding-top: var(--header-height);
    }

    body {
      font-family: var(--font-stack);
      background-color: var(--bg-light);
      color: var(--text-primary);
      line-height: 1.5;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
      -moz-osx-font-smoothing: grayscale;
    }

    .container {
      max-width: var(--max-width);
      margin-left: auto;
      margin-right: auto;
      padding-left: var(--side-padding);
      padding-right: var(--side-padding);
      width: 100%;
    }

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

    a {
      text-decoration: none;
      color: inherit;
    }

    button, .btn {
      cursor: pointer;
      font-family: var(--font-stack);
      border: none;
      background: none;
      transition: transform var(--transition), box-shadow var(--transition), background-color var(--transition), opacity var(--transition);
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      font-weight: 600;
    }

    .btn-primary {
      background-color: var(--primary);
      color: var(--text-white);
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-size: 16px;
      box-shadow: 0 4px 10px rgba(78,110,242,0.25);
    }
    .btn-primary:hover {
      transform: translateY(-2px);
      box-shadow: var(--shadow-btn-hover) var(--primary-glow);
      background-color: #3D5DE0;
    }

    .btn-outline {
      background: transparent;
      color: var(--text-white);
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-size: 16px;
      border: 1px solid rgba(255,255,255,0.5);
      backdrop-filter: blur(4px);
    }
    .btn-outline:hover {
      background: rgba(255,255,255,0.15);
      border-color: #fff;
      transform: translateY(-2px);
      box-shadow: 0 4px 12px rgba(0,0,0,0.2);
    }

    .btn-link {
      color: var(--primary);
      font-weight: 600;
      padding: 10px 20px;
      border-radius: var(--radius-btn);
    }
    .btn-link:hover {
      background-color: var(--primary-light);
    }

    h1, h2, h3, h4 {
      font-weight: 700;
      line-height: 1.3;
    }

    /* 导航 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--header-height);
      z-index: 100;
      background: rgba(255,255,255,0.7);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      border-bottom: 1px solid rgba(229,230,235,0.3);
      transition: background var(--transition), box-shadow var(--transition);
    }
    .header.scrolled {
      background: rgba(255,255,255,0.95);
      box-shadow: 0 2px 12px rgba(0,0,0,0.04);
    }
    .nav {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 100%;
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 var(--side-padding);
    }
    .logo {
      font-size: 24px;
      font-weight: 800;
      color: var(--primary);
      letter-spacing: 1px;
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .logo i {
      font-size: 28px;
    }
    .nav-links {
      display: flex;
      gap: 32px;
      align-items: center;
    }
    .nav-links a {
      font-size: 16px;
      font-weight: 500;
      color: var(--text-primary);
      position: relative;
      padding: 8px 0;
      transition: color var(--transition);
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: var(--primary);
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary);
      transition: width var(--transition);
    }
    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 100%;
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 6px;
      background: none;
      border: none;
      cursor: pointer;
      padding: 8px;
      z-index: 110;
    }
    .hamburger span {
      width: 26px;
      height: 2px;
      background: var(--text-primary);
      border-radius: 2px;
      transition: all var(--transition);
    }
    .mobile-menu {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: #fff;
      display: flex;
      flex-direction: column;
      justify-content: center;
      align-items: center;
      gap: 32px;
      font-size: 22px;
      font-weight: 600;
      transform: translateX(100%);
      transition: transform 0.3s ease;
      z-index: 100;
    }
    .mobile-menu.active {
      transform: translateX(0);
    }
    .mobile-menu a {
      color: var(--text-primary);
    }
    .close-menu {
      position: absolute;
      top: 24px;
      right: 24px;
      font-size: 32px;
      background: none;
      border: none;
      cursor: pointer;
    }

    /* 首屏 */
    .hero {
      min-height: 90vh;
      display: flex;
      align-items: center;
      background: radial-gradient(circle at 30% 50%, #1A1F3A, #0A0E27);
      position: relative;
      overflow: hidden;
      margin-top: 0;
      padding: 120px 0 80px;
    }
    .hero::before {
      content: '';
      position: absolute;
      inset: 0;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      opacity: 0.35;
      mix-blend-mode: overlay;
    }
    .hero-content {
      position: relative;
      z-index: 2;
      display: flex;
      align-items: center;
      gap: 60px;
      flex-wrap: wrap;
    }
    .hero-text {
      flex: 1 1 500px;
    }
    .hero-text h1 {
      font-size: 44px;
      color: #fff;
      margin-bottom: 24px;
      line-height: 1.2;
      font-weight: 800;
    }
    .hero-text .subtitle {
      font-size: 18px;
      color: #A8B1CC;
      margin-bottom: 40px;
      max-width: 550px;
    }
    .hero-actions {
      display: flex;
      gap: 20px;
      flex-wrap: wrap;
    }
    .hero-visual {
      flex: 1 1 400px;
      display: flex;
      justify-content: center;
    }
    .hero-visual img {
      max-height: 360px;
      border-radius: var(--radius-card);
      box-shadow: 0 20px 40px rgba(0,0,0,0.5);
      background: rgba(255,255,255,0.05);
    }

    /* 通用区块 */
    section {
      padding: 80px 0;
    }
    .section-title {
      text-align: center;
      margin-bottom: 56px;
    }
    .section-title h2 {
      font-size: 32px;
      color: var(--text-primary);
      margin-bottom: 12px;
    }
    .section-title p {
      font-size: 16px;
      color: var(--text-secondary);
      max-width: 600px;
      margin: 0 auto;
    }

    /* 痛点卡片 */
    .pain-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
      gap: 24px;
    }
    .pain-card {
      background: var(--bg-white);
      padding: 32px 24px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
      transition: box-shadow var(--transition), transform var(--transition);
    }
    .pain-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-card-hover);
    }
    .pain-icon {
      font-size: 32px;
      color: var(--primary);
      margin-bottom: 20px;
    }
    .pain-card h3 {
      font-size: 20px;
      margin-bottom: 12px;
    }
    .pain-card p {
      color: var(--text-secondary);
      font-size: 15px;
    }

    /* 解决方案交替 */
    .solution-row {
      display: flex;
      align-items: center;
      gap: 60px;
      margin-bottom: 80px;
      flex-wrap: wrap;
    }
    .solution-row.reverse {
      flex-direction: row-reverse;
    }
    .solution-img, .solution-text {
      flex: 1 1 400px;
    }
    .solution-img img {
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
    }
    .solution-text h3 {
      font-size: 26px;
      margin-bottom: 16px;
    }
    .solution-text p {
      color: var(--text-secondary);
      margin-bottom: 20px;
      font-size: 16px;
    }
    .data-badge {
      display: inline-block;
      background: var(--primary-light);
      color: var(--primary);
      font-weight: 700;
      padding: 6px 14px;
      border-radius: 20px;
      font-size: 14px;
      margin-right: 8px;
      margin-bottom: 8px;
    }

    /* 数据区 */
    .stats-grid {
      display: flex;
      flex-wrap: wrap;
      gap: 24px;
      justify-content: center;
    }
    .stat-item {
      background: var(--bg-white);
      flex: 1 1 200px;
      padding: 32px 20px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
      text-align: center;
    }
    .stat-number {
      font-size: 42px;
      font-weight: 800;
      color: var(--primary);
      margin-bottom: 8px;
    }
    .stat-label {
      color: var(--text-secondary);
      font-size: 15px;
    }

    /* 证言 */
    .testimonial-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
      gap: 24px;
    }
    .testimonial-card {
      background: var(--bg-white);
      padding: 32px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
      position: relative;
    }
    .testimonial-card .quote-icon {
      font-size: 40px;
      color: var(--primary-light);
      position: absolute;
      top: 16px;
      right: 24px;
    }
    .testimonial-text {
      font-size: 16px;
      color: var(--text-primary);
      margin-bottom: 24px;
      font-style: italic;
    }
    .client-info {
      display: flex;
      align-items: center;
      gap: 12px;
    }
    .client-avatar {
      width: 48px;
      height: 48px;
      border-radius: 50%;
      background: var(--bg-light);
      object-fit: cover;
    }
    .stars {
      color: var(--warning);
      margin-bottom: 6px;
    }

    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      border-bottom: 1px solid var(--border-light);
      margin-bottom: 8px;
    }
    .faq-question {
      width: 100%;
      display: flex;
      justify-content: space-between;
      align-items: center;
      padding: 18px 8px;
      font-weight: 600;
      font-size: 18px;
      background: transparent;
      border: none;
      cursor: pointer;
      text-align: left;
      color: var(--text-primary);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease, padding 0.3s ease;
      background: #FAFBFC;
      border-radius: 0 0 8px 8px;
    }
    .faq-answer p {
      padding: 0 16px 16px;
      color: var(--text-secondary);
    }
    .faq-item.active .faq-answer {
      max-height: 160px;
      padding-top: 8px;
    }
    .faq-item.active .faq-arrow {
      transform: rotate(180deg);
    }
    .faq-arrow {
      transition: transform var(--transition);
      color: var(--primary);
    }

    /* CTA 深色区 */
    .cta-dark {
      background: var(--bg-dark);
      text-align: center;
      padding: 80px 0;
      border-radius: 0;
    }
    .cta-dark h2 {
      color: #fff;
      font-size: 32px;
      margin-bottom: 24px;
    }
    .cta-dark .btn-primary {
      font-size: 18px;
      padding: 16px 40px;
    }

    /* 页脚 */
    .footer {
      background: #1F2329;
      color: var(--text-secondary);
      padding: 48px 0 24px;
      font-size: 15px;
    }
    .footer-grid {
      display: flex;
      justify-content: space-between;
      align-items: center;
      flex-wrap: wrap;
      gap: 24px;
      margin-bottom: 32px;
    }
    .footer-links {
      display: flex;
      gap: 24px;
    }
    .footer-links a {
      color: var(--text-secondary);
    }
    .footer-links a:hover {
      color: #fff;
    }
    .copyright {
      text-align: center;
      border-top: 1px solid rgba(255,255,255,0.1);
      padding-top: 24px;
      font-size: 14px;
    }

    @media (max-width: 1024px) {
      .hero-content {
        gap: 40px;
      }
    }

    @media (max-width: 768px) {
      .nav-links {
        display: none;
      }
      .hamburger {
        display: flex;
      }
      .hero {
        padding: 100px 0 60px;
        min-height: auto;
      }
      .hero-text h1 {
        font-size: 32px;
      }
      .hero-text .subtitle {
        font-size: 16px;
      }
      .solution-row, .solution-row.reverse {
        flex-direction: column;
      }
      section {
        padding: 60px 0;
      }
    }

    @media (max-width: 520px) {
      .hero-actions {
        flex-direction: column;
        width: 100%;
      }
      .btn-primary, .btn-outline {
        width: 100%;
        justify-content: center;
      }
    }
    .hidden {
      display: none;
    }