/* roulang page: index */
:root {
      --primary: #0066CC;
      --primary-light: rgba(0, 102, 204, 0.08);
      --secondary: #00A86B;
      --bg: #FAFAFA;
      --surface: #FFFFFF;
      --dark-bg: #1A1A1A;
      --gray-light: #F5F5F5;
      --text-primary: #111111;
      --text-body: #444444;
      --text-secondary: #888888;
      --text-disabled: #CCCCCC;
      --border-light: #EEEEEE;
      --border-input: #DDDDDD;
      --shadow-card: 0 2px 20px rgba(0,0,0,0.04);
      --shadow-hover: 0 8px 30px rgba(0,0,0,0.08);
      --shadow-nav: 2px 0 15px rgba(0,0,0,0.03);
      --radius-btn: 8px;
      --radius-card: 16px;
      --radius-tag: 20px;
      --sidebar-width: 240px;
      --font-stack: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      --transition-base: 0.3s ease;
    }

    * {
      box-sizing: border-box;
    }

    body {
      font-family: var(--font-stack);
      background-color: var(--bg);
      color: var(--text-body);
      line-height: 1.6;
      margin: 0;
      padding: 0;
      display: flex;
      min-height: 100vh;
      overflow-x: hidden;
    }

    h1, h2, h3, h4, h5, h6 {
      color: var(--text-primary);
      font-weight: 600;
      line-height: 1.3;
      margin-bottom: 0.75rem;
    }

    a {
      color: var(--primary);
      text-decoration: none;
      transition: var(--transition-base);
    }
    a:hover {
      color: #004999;
    }

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

    /* 侧边栏 App Shell */
    .app-sidebar {
      position: fixed;
      left: 0;
      top: 0;
      width: var(--sidebar-width);
      height: 100vh;
      background: var(--surface);
      box-shadow: var(--shadow-nav);
      display: flex;
      flex-direction: column;
      z-index: 1030;
      border-right: 1px solid var(--border-light);
      transition: transform 0.3s ease;
    }

    .sidebar-brand {
      padding: 24px 20px 20px;
      border-bottom: 1px solid var(--border-light);
    }
    .brand-logo {
      display: flex;
      align-items: center;
      gap: 12px;
      text-decoration: none;
      color: var(--text-primary);
    }
    .brand-logo img {
      width: 40px;
      height: 40px;
      border-radius: 8px;
    }
    .brand-text {
      font-weight: 700;
      font-size: 18px;
      line-height: 1.2;
    }
    .brand-sub {
      font-size: 11px;
      color: var(--text-secondary);
      font-weight: 400;
    }

    .sidebar-nav {
      flex: 1;
      padding: 24px 12px;
      display: flex;
      flex-direction: column;
      gap: 4px;
    }
    .nav-item {
      display: flex;
      align-items: center;
      gap: 12px;
      padding: 12px 16px;
      border-radius: 8px;
      color: var(--text-body);
      font-size: 14px;
      font-weight: 500;
      transition: var(--transition-base);
      position: relative;
      text-decoration: none;
    }
    .nav-item i {
      width: 20px;
      font-size: 18px;
      color: var(--text-secondary);
      transition: var(--transition-base);
    }
    .nav-item:hover {
      background: var(--gray-light);
      color: var(--primary);
    }
    .nav-item:hover i {
      color: var(--primary);
    }
    .nav-item.active {
      background: var(--primary-light);
      color: var(--primary);
    }
    .nav-item.active i {
      color: var(--primary);
    }
    .nav-item.active::before {
      content: '';
      position: absolute;
      left: 0;
      top: 50%;
      transform: translateY(-50%);
      height: 20px;
      width: 4px;
      background: var(--primary);
      border-radius: 0 4px 4px 0;
    }

    .sidebar-footer {
      padding: 16px 20px 24px;
      border-top: 1px solid var(--border-light);
    }
    .btn-sidebar-contact {
      background: var(--primary);
      color: white;
      border: none;
      padding: 12px 16px;
      border-radius: var(--radius-btn);
      font-weight: 500;
      width: 100%;
      transition: var(--transition-base);
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
    }
    .btn-sidebar-contact:hover {
      background: #004999;
      transform: scale(1.02);
    }

    /* 主内容区 */
    .main-content {
      margin-left: var(--sidebar-width);
      flex: 1;
      width: calc(100% - var(--sidebar-width));
      transition: margin 0.3s;
    }

    /* 移动端顶部导航 */
    .mobile-header {
      display: none;
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: white;
      z-index: 1040;
      padding: 12px 20px;
      box-shadow: 0 2px 10px rgba(0,0,0,0.04);
      align-items: center;
      justify-content: space-between;
    }
    .mobile-logo {
      display: flex;
      align-items: center;
      gap: 10px;
      font-weight: 700;
      font-size: 18px;
    }
    .mobile-logo img {
      width: 32px;
      height: 32px;
    }
    .hamburger {
      font-size: 24px;
      background: none;
      border: none;
      color: var(--text-primary);
      width: 44px;
      height: 44px;
      display: flex;
      align-items: center;
      justify-content: center;
    }

    /* 板块通用 */
    .section {
      padding: 100px 0;
    }
    .section-title {
      font-size: 32px;
      font-weight: 700;
      text-align: center;
      margin-bottom: 12px;
    }
    .section-subtitle {
      font-size: 16px;
      color: var(--text-secondary);
      text-align: center;
      margin-bottom: 48px;
    }

    /* Hero */
    .hero {
      background: var(--bg);
      min-height: 100vh;
      display: flex;
      align-items: center;
      padding: 0;
    }
    .hero-image {
      width: 100%;
      border-radius: 24px;
      box-shadow: 0 20px 35px rgba(0,0,0,0.05);
      animation: floatSlow 6s ease-in-out infinite;
    }
    @keyframes floatSlow {
      0% { transform: translateY(0); }
      50% { transform: translateY(-5px); }
      100% { transform: translateY(0); }
    }
    .trust-badge {
      display: flex;
      align-items: center;
      gap: 8px;
      font-size: 14px;
      color: var(--text-body);
    }
    .trust-badge i {
      color: var(--secondary);
      font-size: 18px;
    }

    /* 优势网格 */
    .feature-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 40px 60px;
    }
    .feature-item {
      display: flex;
      gap: 20px;
      align-items: flex-start;
    }
    .feature-bar {
      width: 4px;
      height: 40px;
      background: var(--primary);
      border-radius: 2px;
      flex-shrink: 0;
      margin-top: 6px;
    }
    .feature-icon {
      font-size: 32px;
      color: var(--primary);
      opacity: 0.8;
    }

    /* 解决方案交替布局 */
    .solution-row {
      display: flex;
      align-items: center;
      gap: 60px;
      margin-bottom: 100px;
    }
    .solution-row.reverse {
      flex-direction: row-reverse;
    }
    .solution-img {
      flex: 1;
      border-radius: 12px;
      overflow: hidden;
      filter: grayscale(20%);
      background: var(--gray-light);
    }
    .solution-text {
      flex: 1;
    }
    .link-underline {
      position: relative;
      display: inline-block;
      font-weight: 500;
      color: var(--primary);
    }
    .link-underline::after {
      content: '';
      position: absolute;
      bottom: -2px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary);
      transition: width 0.3s ease;
    }
    .link-underline:hover::after {
      width: 100%;
    }

    /* 场景卡片 */
    .scenario-card {
      background: var(--surface);
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
      overflow: hidden;
      transition: var(--transition-base);
      height: fit-content;
    }
    .scenario-card.middle {
      margin-top: -20px;
    }
    .scenario-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    .tag-outline {
      border: 1px solid var(--primary);
      color: var(--primary);
      padding: 4px 12px;
      border-radius: var(--radius-tag);
      font-size: 11px;
      background: transparent;
    }

    /* 案例 */
    .case-card {
      background: var(--surface);
      border-radius: var(--radius-card);
      overflow: hidden;
    }
    .client-logo-grid {
      display: flex;
      justify-content: space-around;
      align-items: center;
      border-top: 1px solid var(--border-light);
      padding-top: 30px;
      filter: grayscale(100%);
      opacity: 0.7;
      transition: 0.3s;
    }
    .client-logo-grid img:hover {
      filter: grayscale(0%);
      opacity: 1;
    }

    /* 价格 */
    .pricing-card {
      background: var(--surface);
      border-radius: 20px;
      padding: 32px;
      box-shadow: var(--shadow-card);
      position: relative;
      transition: var(--transition-base);
      height: 100%;
    }
    .pricing-card.recommended {
      border-left: 4px solid var(--primary);
      box-shadow: var(--shadow-hover);
    }
    .price-number {
      font-size: 48px;
      font-weight: 700;
      color: var(--primary);
    }

    /* FAQ */
    .accordion-button {
      font-weight: 500;
      font-size: 16px;
      background: white;
      box-shadow: none;
      padding: 18px 20px;
    }
    .accordion-button:not(.collapsed) {
      background: var(--gray-light);
      color: var(--primary);
    }
    .accordion-body {
      background: var(--gray-light);
      font-size: 14px;
      line-height: 1.8;
    }

    /* CTA */
    .cta-section {
      background-color: var(--primary-light);
      background-image: radial-gradient(circle at 20% 30%, rgba(0,102,204,0.03) 0%, transparent 40%);
    }

    /* 页脚 */
    .footer {
      background: var(--dark-bg);
      color: #BBBBBB;
    }
    .footer a {
      color: #BBBBBB;
    }
    .footer a:hover {
      color: var(--primary);
    }

    @media (max-width: 768px) {
      .app-sidebar {
        transform: translateX(-100%);
      }
      .app-sidebar.open {
        transform: translateX(0);
      }
      .main-content {
        margin-left: 0;
        width: 100%;
      }
      .mobile-header {
        display: flex;
      }
      .section {
        padding: 60px 0;
      }
      .hero {
        min-height: auto;
        padding-top: 80px;
      }
      .feature-grid {
        grid-template-columns: 1fr;
      }
      .solution-row {
        flex-direction: column !important;
      }
      .scenario-card.middle {
        margin-top: 0;
      }
    }