/* roulang page: index */
/* ----- 设计变量 ----- */
    :root {
      --primary: #4E6EF2;
      --primary-hover: #3A5CE0;
      --primary-soft: rgba(78, 110, 242, 0.08);
      --primary-border: rgba(78, 110, 242, 0.25);
      --green: #00B578;
      --orange: #FF9F0A;
      --red: #FA5151;
      --bg: #F5F6FA;
      --surface: #FFFFFF;
      --text: #1F2329;
      --text-secondary: #86909C;
      --border-light: #E5E8EF;
      --shadow-sm: 0 2px 12px rgba(31, 35, 41, 0.04);
      --shadow-md: 0 8px 24px rgba(31, 35, 41, 0.08);
      --shadow-nav: 0 2px 8px rgba(0,0,0,0.06);
      --radius-card: 12px;
      --radius-btn: 12px;
      --radius-full: 50px;
      --font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      --transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
      --container-max: 1200px;
      --section-gap: 80px;
    }

    /* ----- 基础重置 ----- */
    *, *::before, *::after {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }
    html {
      scroll-behavior: smooth;
      -webkit-font-smoothing: antialiased;
    }
    body {
      font-family: var(--font-family);
      background: var(--bg);
      color: var(--text);
      line-height: 1.6;
      font-size: 16px;
      font-weight: 400;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition);
    }
    button, input {
      font-family: inherit;
      border: none;
      outline: none;
      background: none;
    }
    .container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
    }

    /* ----- 按钮系统 ----- */
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      font-weight: 500;
      border-radius: var(--radius-btn);
      cursor: pointer;
      transition: var(--transition);
      font-size: 16px;
      padding: 12px 28px;
      line-height: 1.4;
    }
    .btn-primary {
      background: var(--primary);
      color: white;
      box-shadow: 0 2px 8px rgba(78,110,242,0.2);
    }
    .btn-primary:hover {
      background: var(--primary-hover);
      box-shadow: 0 4px 14px rgba(78,110,242,0.35);
      transform: translateY(-1px);
    }
    .btn-primary:focus-visible {
      box-shadow: 0 0 0 3px rgba(78, 110, 242, 0.3);
    }
    .btn-secondary {
      background: rgba(78, 110, 242, 0.05);
      color: var(--primary);
      border: 1px solid rgba(78, 110, 242, 0.2);
    }
    .btn-secondary:hover {
      background: rgba(78, 110, 242, 0.1);
      border-color: var(--primary);
    }
    .btn-ghost {
      color: var(--primary);
      padding: 8px 16px;
    }
    .btn-ghost:hover {
      text-decoration: underline;
      background: var(--primary-soft);
    }
    .btn-large {
      font-size: 18px;
      padding: 16px 40px;
      border-radius: var(--radius-card);
    }

    /* 脉冲动画（仅用于CTA大按钮） */
    @keyframes pulse {
      0% { box-shadow: 0 0 0 0 rgba(78, 110, 242, 0.3); }
      70% { box-shadow: 0 0 0 12px rgba(78, 110, 242, 0); }
      100% { box-shadow: 0 0 0 0 rgba(78, 110, 242, 0); }
    }
    .btn-pulse {
      animation: pulse 2s infinite;
    }

    /* ----- 导航 (PC + 移动底部胶囊) ----- */
    .navbar {
      position: sticky;
      top: 0;
      z-index: 100;
      background: var(--surface);
      transition: var(--transition);
      box-shadow: none;
    }
    .navbar.scrolled {
      box-shadow: var(--shadow-nav);
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 68px;
    }
    .logo {
      display: flex;
      align-items: baseline;
      gap: 6px;
      font-weight: 700;
      font-size: 24px;
      color: var(--primary);
      letter-spacing: 0.5px;
    }
    .logo .domain {
      font-size: 13px;
      font-weight: 400;
      color: var(--text-secondary);
      margin-left: 4px;
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
      list-style: none;
    }
    .nav-links a {
      font-size: 15px;
      font-weight: 500;
      color: var(--text);
      padding: 8px 0;
      position: relative;
      white-space: nowrap;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary);
      border-radius: 1px;
      transition: width 0.2s ease;
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: var(--primary);
    }
    .nav-links a.active::after {
      width: 100%;
    }
    .nav-cta {
      margin-left: 16px;
    }

    /* 移动端底部导航 */
    .mobile-bottom-nav {
      display: none;
      position: fixed;
      bottom: 0;
      left: 0;
      right: 0;
      background: var(--surface);
      box-shadow: 0 -2px 12px rgba(0,0,0,0.04);
      z-index: 110;
      padding: 6px 16px;
      justify-content: space-around;
      align-items: center;
      height: 64px;
    }
    .mobile-nav-item {
      display: flex;
      flex-direction: column;
      align-items: center;
      font-size: 12px;
      color: var(--text-secondary);
      gap: 4px;
      font-weight: 500;
    }
    .mobile-nav-item svg {
      width: 22px;
      height: 22px;
      stroke: currentColor;
      fill: none;
      stroke-width: 1.8;
    }
    .mobile-nav-item.active {
      color: var(--primary);
    }

    /* ----- 板块通用 ----- */
    section {
      padding: var(--section-gap) 0;
    }
    .section-title {
      text-align: center;
      margin-bottom: 48px;
    }
    .section-title h2 {
      font-size: 28px;
      font-weight: 600;
      line-height: 1.4;
      color: var(--text);
      margin-bottom: 12px;
    }
    .section-title p {
      color: var(--text-secondary);
      font-size: 16px;
    }

    /* ----- Hero ----- */
    .hero {
      background: radial-gradient(circle at 80% 20%, rgba(78,110,242,0.08) 0%, transparent 60%), var(--bg);
      padding: 40px 0 80px;
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 48px;
      align-items: center;
    }
    .hero-content h1 {
      font-size: 36px;
      font-weight: 700;
      line-height: 1.3;
      color: var(--text);
      margin-bottom: 20px;
      animation: fadeInUp 0.6s ease;
    }
    .hero-content .sub {
      font-size: 16px;
      color: var(--text-secondary);
      margin-bottom: 32px;
      line-height: 1.6;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .hero-image {
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-md);
      min-height: 320px;
      width: 100%;
      background-color: #E8ECF4;
    }
    @keyframes fadeInUp {
      0% { opacity: 0; transform: translateY(18px); }
      100% { opacity: 1; transform: translateY(0); }
    }

    /* 痛点卡片 */
    .pain-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .pain-card {
      background: #F0F2FA;
      border-radius: var(--radius-card);
      padding: 28px 24px;
      display: flex;
      gap: 18px;
      align-items: flex-start;
      transition: var(--transition);
    }
    .pain-card:hover {
      background: white;
      box-shadow: var(--shadow-sm);
    }
    .pain-icon {
      color: var(--orange);
      font-size: 24px;
      line-height: 1;
      font-weight: 600;
    }
    .pain-text h3 {
      font-size: 20px;
      font-weight: 600;
      margin-bottom: 8px;
    }
    .pain-text p {
      color: var(--text-secondary);
      font-size: 14px;
    }

    /* 解决方案卡片 */
    .solutions-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
    }
    .solution-card {
      background: var(--surface);
      border-radius: var(--radius-card);
      padding: 28px 20px;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      display: flex;
      flex-direction: column;
      align-items: flex-start;
      position: relative;
    }
    .solution-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-md);
    }
    .solution-icon {
      width: 64px;
      height: 64px;
      background: rgba(78,110,242,0.08);
      border-radius: 16px;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 20px;
      color: var(--primary);
    }
    .solution-card h3 {
      font-size: 20px;
      font-weight: 600;
      margin-bottom: 12px;
    }
    .solution-card p {
      color: var(--text-secondary);
      font-size: 14px;
      margin-bottom: 18px;
      flex: 1;
    }

    /* 数据墙 */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
      text-align: center;
    }
    .stat-item {
      background: var(--surface);
      border-radius: var(--radius-card);
      padding: 32px 16px;
      box-shadow: var(--shadow-sm);
      background: linear-gradient(135deg, rgba(78,110,242,0.02) 0%, rgba(0,181,120,0.02) 100%);
    }
    .stat-number {
      font-size: 48px;
      font-weight: 700;
      color: var(--primary);
      line-height: 1.1;
    }
    .stat-label {
      color: var(--text-secondary);
      font-size: 14px;
      margin-top: 8px;
    }

    /* 客户证言 */
    .testimonials-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .testimonial-card {
      background: var(--surface);
      border-radius: var(--radius-card);
      padding: 28px;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
    }
    .testimonial-card:hover {
      box-shadow: var(--shadow-md);
    }
    .testimonial-header {
      display: flex;
      align-items: center;
      gap: 16px;
      margin-bottom: 20px;
    }
    .avatar {
      width: 48px;
      height: 48px;
      border-radius: 50%;
      background: #E5E8EF;
      background-image: url('/assets/images/coverpic/cover-2.webp');
      background-size: cover;
    }
    .testimonial-text {
      font-style: italic;
      margin-bottom: 16px;
      color: var(--text);
    }
    .stars {
      color: var(--orange);
      letter-spacing: 2px;
    }

    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
      display: flex;
      flex-direction: column;
      gap: 16px;
    }
    .faq-item {
      background: var(--surface);
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      overflow: hidden;
    }
    .faq-question {
      width: 100%;
      padding: 20px 24px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 500;
      font-size: 18px;
      cursor: pointer;
      transition: background 0.2s;
    }
    .faq-question:hover {
      background: #F8F9FC;
    }
    .faq-icon {
      font-size: 22px;
      transition: transform 0.25s ease;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease, padding 0.2s;
      background: #F8F9FC;
      padding: 0 24px;
    }
    .faq-item.open .faq-answer {
      max-height: 200px;
      padding: 16px 24px;
    }
    .faq-item.open .faq-icon {
      transform: rotate(45deg);
    }

    /* CTA */
    .cta-section {
      background: var(--primary);
      color: white;
      border-radius: 24px;
      padding: 64px 32px;
      text-align: center;
      margin: 0 24px;
    }
    .cta-section h2 {
      font-size: 28px;
      font-weight: 600;
      margin-bottom: 16px;
    }
    .cta-section p {
      margin-bottom: 32px;
      opacity: 0.9;
    }
    .btn-light {
      background: white;
      color: var(--primary);
      font-weight: 600;
    }

    /* 页脚 */
    .footer {
      background: #1F2329;
      color: #86909C;
      padding: 48px 0 24px;
      margin-top: 80px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr;
      gap: 40px;
    }
    .footer a {
      color: #86909C;
    }
    .footer a:hover {
      color: var(--primary);
    }
    .copyright {
      border-top: 0.5px solid #86909C;
      margin-top: 32px;
      padding-top: 20px;
      text-align: center;
      font-size: 14px;
    }

    /* ----- 响应式 ----- */
    @media (max-width: 1024px) {
      .solutions-grid { grid-template-columns: repeat(2, 1fr); }
    }
    @media (max-width: 768px) {
      .container { padding: 0 16px; }
      section { padding: 60px 0; }
      .hero-grid { grid-template-columns: 1fr; }
      .hero-content h1 { font-size: 28px; }
      .pain-grid, .testimonials-grid { grid-template-columns: 1fr; }
      .solutions-grid { grid-template-columns: 1fr; }
      .stats-grid { grid-template-columns: repeat(2, 1fr); }
      .nav-links, .nav-cta { display: none; }
      .mobile-bottom-nav { display: flex; }
      .footer-grid { grid-template-columns: 1fr; }
      .cta-section { margin: 0 16px; }
    }