/* roulang page: index */
:root {
      --primary: #2E5BFF;
      --primary-hover: #1E4BD8;
      --primary-light: #EEF1FF;
      --accent: #FF6B35;
      --accent-hover: #E55A2B;
      --success: #00B578;
      --warning: #FF9F0A;
      --error: #FA5151;
      --bg: #F5F6FA;
      --white: #FFFFFF;
      --dark-bg: #1A2236;
      --text-main: #1F2329;
      --text-secondary: #86909C;
      --text-disabled: #C0C4CC;
      --text-on-dark: #FFFFFF;
      --shadow-card: 0 2px 12px rgba(0,0,0,0.06);
      --shadow-card-hover: 0 8px 24px rgba(0,0,0,0.10);
      --shadow-nav: 0 2px 8px rgba(0,0,0,0.04);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-input: 8px;
      --radius-capsule: 24px;
      --space-section: 80px;
      --space-card-padding: 24px;
      --max-width: 1200px;
      --header-height: 64px;
      --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
      --transition: 0.2s ease;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    html {
      scroll-behavior: smooth;
    }
    body {
      font-family: var(--font-family);
      background-color: var(--bg);
      color: var(--text-main);
      line-height: 1.6;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }
    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
    }
    @media (max-width: 768px) {
      .container {
        padding: 0 16px;
      }
    }
    /* 导航 */
    .site-header {
      position: sticky;
      top: 0;
      z-index: 100;
      background: var(--white);
      box-shadow: var(--shadow-nav);
      height: var(--header-height);
      display: flex;
      align-items: center;
    }
    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }
    .logo {
      display: flex;
      align-items: baseline;
      gap: 6px;
      text-decoration: none;
      color: var(--text-main);
      font-weight: 700;
      font-size: 20px;
      letter-spacing: -0.3px;
    }
    .logo .brand {
      color: var(--primary);
    }
    .logo .domain {
      font-size: 12px;
      font-weight: 400;
      color: var(--text-secondary);
      margin-left: 2px;
    }
    .nav-menu {
      display: flex;
      align-items: center;
      gap: 28px;
      list-style: none;
    }
    .nav-menu a {
      text-decoration: none;
      font-size: 15px;
      font-weight: 500;
      color: var(--text-main);
      padding: 8px 0;
      border-bottom: 2px solid transparent;
      transition: color var(--transition), border-color var(--transition);
    }
    .nav-menu a:hover,
    .nav-menu a.active {
      color: var(--primary);
      border-bottom-color: var(--primary);
    }
    .header-cta {
      background: var(--primary);
      color: white;
      border: none;
      padding: 10px 22px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 14px;
      cursor: pointer;
      transition: background var(--transition), transform var(--transition);
      text-decoration: none;
      display: inline-block;
    }
    .header-cta:hover {
      background: var(--primary-hover);
      transform: scale(1.02);
    }
    .mobile-toggle {
      display: none;
      background: none;
      border: none;
      font-size: 24px;
      cursor: pointer;
      color: var(--text-main);
    }
    @media (max-width: 1024px) {
      .nav-menu {
        display: none;
      }
      .header-cta.desktop {
        display: none;
      }
      .mobile-toggle {
        display: block;
      }
    }
    .mobile-drawer {
      position: fixed;
      top: 0;
      right: 0;
      width: 280px;
      height: 100vh;
      background: var(--white);
      box-shadow: -4px 0 20px rgba(0,0,0,0.15);
      transform: translateX(100%);
      transition: transform 0.25s ease;
      z-index: 200;
      display: flex;
      flex-direction: column;
      padding: 24px;
    }
    .mobile-drawer.open {
      transform: translateX(0);
    }
    .drawer-close {
      align-self: flex-end;
      background: none;
      border: none;
      font-size: 28px;
      cursor: pointer;
    }
    .drawer-menu {
      list-style: none;
      margin-top: 32px;
    }
    .drawer-menu li {
      margin-bottom: 20px;
    }
    .drawer-menu a {
      font-size: 18px;
      font-weight: 600;
      color: var(--text-main);
      text-decoration: none;
    }
    .overlay {
      position: fixed;
      inset: 0;
      background: rgba(0,0,0,0.3);
      z-index: 150;
      display: none;
    }
    .overlay.show {
      display: block;
    }
    /* 板块通用 */
    section {
      padding: var(--space-section) 0;
    }
    @media (max-width: 768px) {
      section {
        padding: 60px 0;
      }
    }
    .section-title {
      font-size: 36px;
      font-weight: 700;
      line-height: 1.3;
      margin-bottom: 16px;
      color: var(--text-main);
    }
    .section-sub {
      font-size: 18px;
      color: var(--text-secondary);
      max-width: 700px;
    }
    @media (max-width: 768px) {
      .section-title {
        font-size: 28px;
      }
    }
    /* Hero */
    #hero {
      background: linear-gradient(135deg, #F5F6FA 0%, #E8ECF1 100%);
      padding: 0;
      min-height: 85vh;
      display: flex;
      align-items: center;
      position: relative;
      overflow: hidden;
    }
    .hero-grid {
      display: flex;
      align-items: center;
      gap: 60px;
      flex-wrap: wrap;
    }
    .hero-text {
      flex: 1 1 400px;
    }
    .hero-title {
      font-size: 48px;
      font-weight: 700;
      line-height: 1.2;
      margin-bottom: 20px;
    }
    .hero-desc {
      font-size: 18px;
      color: var(--text-secondary);
      margin-bottom: 32px;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--primary);
      color: white;
      border: none;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 16px;
      cursor: pointer;
      transition: background var(--transition), transform var(--transition);
      text-decoration: none;
      display: inline-block;
    }
    .btn-primary:hover {
      background: var(--primary-hover);
      transform: translateY(-1px);
    }
    .btn-secondary {
      background: transparent;
      color: var(--primary);
      border: 1.5px solid var(--primary);
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 16px;
      cursor: pointer;
      transition: background var(--transition);
      text-decoration: none;
    }
    .btn-secondary:hover {
      background: var(--primary-light);
    }
    .hero-image {
      flex: 1 1 400px;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      border-radius: 24px;
      min-height: 360px;
      box-shadow: var(--shadow-card-hover);
    }
    @media (max-width: 768px) {
      .hero-title {
        font-size: 32px;
      }
      .hero-grid {
        flex-direction: column;
        gap: 40px;
      }
      .hero-image {
        width: 100%;
        min-height: 260px;
      }
    }
    /* 痛点卡片 */
    .cards-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      margin-top: 40px;
    }
    .pain-card {
      background: var(--white);
      padding: var(--space-card-padding);
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
      transition: all 0.3s ease;
    }
    .pain-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-card-hover);
    }
    .pain-icon {
      font-size: 32px;
      margin-bottom: 16px;
      color: var(--primary);
    }
    .pain-title {
      font-size: 20px;
      font-weight: 700;
      margin-bottom: 8px;
    }
    @media (max-width: 768px) {
      .cards-grid {
        grid-template-columns: 1fr;
      }
    }
    /* 解决方案 四列不对称 */
    .solution-grid {
      display: grid;
      grid-template-columns: 1.2fr 1fr 1fr 1.2fr;
      gap: 24px;
      margin-top: 40px;
    }
    .solution-card {
      background: var(--white);
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-card);
      transition: all 0.3s ease;
      display: flex;
      flex-direction: column;
    }
    .solution-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-card-hover);
    }
    .solution-img {
      height: 160px;
      background-size: cover;
      background-position: center;
    }
    .solution-content {
      padding: 20px;
    }
    .solution-name {
      font-weight: 700;
      font-size: 18px;
      margin-bottom: 8px;
    }
    @media (max-width: 1024px) {
      .solution-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }
    @media (max-width: 520px) {
      .solution-grid {
        grid-template-columns: 1fr;
      }
    }
    /* 数据带 */
    .stats-bar {
      display: flex;
      justify-content: space-around;
      flex-wrap: wrap;
      gap: 32px;
      background: var(--white);
      padding: 40px 24px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
      margin-top: 40px;
    }
    .stat-item {
      text-align: center;
    }
    .stat-number {
      font-size: 48px;
      font-weight: 700;
      color: var(--primary);
      line-height: 1.1;
    }
    .stat-desc {
      color: var(--text-secondary);
      font-size: 14px;
    }
    /* 客户证言 */
    .testimonial-grid {
      display: flex;
      gap: 24px;
      overflow-x: auto;
      padding-bottom: 16px;
      margin-top: 32px;
    }
    .testimonial-card {
      min-width: 280px;
      background: #F0F1F5;
      border-radius: var(--radius-card);
      padding: 24px;
      flex-shrink: 0;
    }
    .testimonial-text {
      font-style: italic;
      margin-bottom: 16px;
    }
    /* FAQ */
    .faq-list {
      margin-top: 32px;
    }
    .faq-item {
      background: var(--white);
      border-radius: var(--radius-card);
      margin-bottom: 12px;
      box-shadow: var(--shadow-card);
    }
    .faq-question {
      width: 100%;
      background: none;
      border: none;
      padding: 18px 24px;
      font-weight: 700;
      font-size: 16px;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
      text-align: left;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      background: #F9FAFB;
      padding: 0 24px;
    }
    .faq-answer.open {
      max-height: 200px;
      padding: 16px 24px;
    }
    /* CTA */
    #cta {
      background: var(--dark-bg);
      color: white;
      text-align: center;
    }
    .cta-title {
      font-size: 36px;
      font-weight: 700;
    }
    .btn-accent {
      background: var(--accent);
      color: white;
      border: none;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 700;
      font-size: 16px;
      margin-top: 24px;
      cursor: pointer;
      transition: background var(--transition);
    }
    .btn-accent:hover {
      background: var(--accent-hover);
    }
    /* 页脚 */
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 32px;
      color: #CBD5E0;
    }
    .footer-brand {
      font-weight: 700;
      color: white;
      font-size: 18px;
    }
    .footer a {
      color: #86909C;
      text-decoration: none;
    }
    .footer a:hover {
      color: white;
    }
    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
    }