/* roulang page: index */
:root {
      --primary: #1d4ed8;
      --primary-hover: #1e40af;
      --accent: #0ea5e9;
      --success: #22c55e;
      --dark-surface: #0f172a;
      --dark-card: #1e293b;
      --bg-base: #f8fafc;
      --text-main: #1e293b;
      --text-muted: #64748b;
      --text-light: #ffffff;
      --border-color: #e2e8f0;
      --radius-sm: 8px;
      --radius-md: 12px;
      --radius-lg: 18px;
      --shadow-sm: 0 4px 6px -1px rgba(15, 23, 42, 0.05);
      --shadow-card: 0 10px 25px -5px rgba(15, 23, 42, 0.04), 0 8px 10px -6px rgba(15, 23, 42, 0.03);
      --shadow-hover: 0 20px 25px -5px rgba(29, 78, 216, 0.08);
      --transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
    }

    * { box-sizing: border-box; margin: 0; padding: 0; }
    html { scroll-behavior: smooth; }
    body {
      font-family: system-ui, -apple-system, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
      background-color: var(--bg-base);
      color: var(--text-main);
      line-height: 1.7;
      overflow-x: hidden;
    }
    a { text-decoration: none; color: inherit; transition: var(--transition); }
    img { max-width: 100%; height: auto; display: block; }

    /* 侧边栏布局：桌面端左侧固定，移动端顶部吸顶 */
    .sidebar-navigation {
      position: fixed;
      top: 0;
      left: 0;
      bottom: 0;
      width: 260px;
      background: #ffffff;
      border-right: 1px solid var(--border-color);
      z-index: 1040;
      display: flex;
      flex-direction: column;
      justify-content: space-between;
      padding: 1.75rem 1.25rem;
    }
    .brand-box {
      display: flex;
      align-items: center;
      gap: 12px;
      padding-bottom: 1.5rem;
      border-bottom: 1px solid var(--border-color);
    }
    .brand-icon {
      width: 44px;
      height: 44px;
      background: linear-gradient(135deg, var(--primary), var(--accent));
      border-radius: var(--radius-md);
      display: flex;
      align-items: center;
      justify-content: center;
      color: #fff;
      font-size: 1.25rem;
      box-shadow: 0 4px 12px rgba(29, 78, 216, 0.25);
    }
    .brand-text {
      font-size: 1.25rem;
      font-weight: 700;
      color: var(--text-main);
      letter-spacing: -0.5px;
    }
    .nav-menu {
      list-style: none;
      padding: 0;
      margin: 1.5rem 0;
      display: flex;
      flex-direction: column;
      gap: 8px;
    }
    .nav-item-link {
      display: flex;
      align-items: center;
      gap: 12px;
      padding: 10px 14px;
      font-size: 0.95rem;
      font-weight: 500;
      color: var(--text-muted);
      border-radius: var(--radius-sm);
    }
    .nav-item-link:hover, .nav-item-link.active {
      color: var(--primary);
      background-color: #eff6ff;
    }
    .sidebar-status-box {
      background: #f1f5f9;
      border-radius: var(--radius-md);
      padding: 1rem;
      border: 1px solid var(--border-color);
    }
    .sidebar-status-box .badge-version {
      font-size: 0.75rem;
      background: #dbeafe;
      color: var(--primary);
      font-weight: 600;
      padding: 2px 8px;
      border-radius: 4px;
    }

    /* 右侧主视窗内容区 */
    .app-main-content {
      margin-left: 260px;
      min-height: 100vh;
      display: flex;
      flex-direction: column;
    }

    /* 移动端顶栏 */
    .mobile-header-navbar {
      display: none;
      position: fixed;
      top: 0;
      left: 0;
      right: 0;
      height: 64px;
      background: #ffffff;
      border-bottom: 1px solid var(--border-color);
      z-index: 1050;
      padding: 0 1rem;
      align-items: center;
      justify-content: space-between;
    }

    /* 通用版块样式 */
    section {
      padding: 5.5rem 0;
      position: relative;
    }
    .section-alt {
      background-color: #ffffff;
    }
    .section-header {
      margin-bottom: 3.5rem;
    }
    .section-tag {
      display: inline-flex;
      align-items: center;
      gap: 6px;
      font-size: 0.85rem;
      font-weight: 600;
      color: var(--primary);
      background: #eff6ff;
      padding: 6px 14px;
      border-radius: 999px;
      margin-bottom: 0.75rem;
    }
    .section-title {
      font-size: 2.1rem;
      font-weight: 800;
      color: var(--text-main);
      line-height: 1.3;
      margin-bottom: 0.85rem;
    }
    .section-desc {
      font-size: 1.05rem;
      color: var(--text-muted);
      max-width: 680px;
      line-height: 1.75;
    }

    /* 卡片体系 */
    .app-card {
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-lg);
      padding: 1.75rem;
      box-shadow: var(--shadow-card);
      transition: var(--transition);
      height: 100%;
      display: flex;
      flex-direction: column;
    }
    .app-card:hover {
      box-shadow: var(--shadow-hover);
      transform: translateY(-4px);
      border-color: #bfdbfe;
    }
    .app-card-icon {
      width: 52px;
      height: 52px;
      background: #eff6ff;
      color: var(--primary);
      border-radius: var(--radius-md);
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 1.4rem;
      margin-bottom: 1.25rem;
    }
    .app-card-title {
      font-size: 1.25rem;
      font-weight: 700;
      margin-bottom: 0.75rem;
      color: var(--text-main);
    }
    .app-card-text {
      color: var(--text-muted);
      font-size: 0.95rem;
      line-height: 1.65;
      margin-bottom: 1.25rem;
      flex-grow: 1;
    }

    /* 按钮组 */
    .btn-custom-primary {
      background-color: var(--primary);
      color: #ffffff;
      padding: 12px 28px;
      font-size: 1rem;
      font-weight: 600;
      border-radius: var(--radius-md);
      border: 1px solid var(--primary);
      display: inline-flex;
      align-items: center;
      gap: 8px;
      box-shadow: 0 4px 14px rgba(29, 78, 216, 0.3);
    }
    .btn-custom-primary:hover {
      background-color: var(--primary-hover);
      color: #ffffff;
      box-shadow: 0 6px 18px rgba(29, 78, 216, 0.4);
    }
    .btn-custom-secondary {
      background-color: #ffffff;
      color: var(--text-main);
      padding: 12px 26px;
      font-size: 1rem;
      font-weight: 600;
      border-radius: var(--radius-md);
      border: 1px solid var(--border-color);
      display: inline-flex;
      align-items: center;
      gap: 8px;
    }
    .btn-custom-secondary:hover {
      background-color: #f1f5f9;
      color: var(--primary);
      border-color: #cbd5e1;
    }

    /* 首屏 Hero */
    #hero {
      padding-top: 5rem;
      padding-bottom: 5.5rem;
      background: linear-gradient(180deg, #f0f7ff 0%, #f8fafc 100%);
      border-bottom: 1px solid var(--border-color);
    }
    .hero-h1 {
      font-size: 2.85rem;
      font-weight: 800;
      line-height: 1.2;
      color: var(--text-main);
      letter-spacing: -0.5px;
      margin-bottom: 1.5rem;
    }
    .hero-lead {
      font-size: 1.15rem;
      color: var(--text-muted);
      line-height: 1.8;
      margin-bottom: 2rem;
    }
    .flash-sale-badge {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      background: rgba(34, 197, 94, 0.1);
      color: #15803d;
      border: 1px solid rgba(34, 197, 94, 0.25);
      padding: 6px 14px;
      border-radius: 999px;
      font-weight: 600;
      font-size: 0.85rem;
      margin-bottom: 1.25rem;
    }
    .hero-screen-stage {
      position: relative;
      border-radius: var(--radius-lg);
      overflow: hidden;
      box-shadow: 0 25px 50px -12px rgba(15, 23, 42, 0.18);
      border: 4px solid #ffffff;
      background: #0f172a;
    }
    .hero-screen-stage img {
      width: 100%;
      height: 380px;
      object-fit: cover;
    }
    .hero-float-card {
      position: absolute;
      bottom: 20px;
      left: 20px;
      right: 20px;
      background: rgba(15, 23, 42, 0.88);
      backdrop-filter: blur(8px);
      border: 1px solid rgba(255, 255, 255, 0.15);
      border-radius: var(--radius-md);
      padding: 14px 18px;
      color: #ffffff;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }

    /* 深色理念区 */
    #dark-vision {
      background-color: var(--dark-surface);
      color: #ffffff;
    }
    .dark-card-box {
      background: rgba(255, 255, 255, 0.05);
      border: 1px solid rgba(255, 255, 255, 0.1);
      border-radius: var(--radius-lg);
      padding: 2.25rem;
      transition: var(--transition);
      height: 100%;
    }
    .dark-card-box:hover {
      background: rgba(255, 255, 255, 0.08);
      border-color: rgba(14, 165, 233, 0.4);
      transform: translateY(-4px);
    }

    /* 数据指标条 */
    #metric-stats {
      background: linear-gradient(135deg, #1e40af, #1d4ed8);
      color: #ffffff;
      padding: 4rem 0;
    }
    .stat-number {
      font-size: 2.75rem;
      font-weight: 800;
      line-height: 1;
      margin-bottom: 0.5rem;
      letter-spacing: -1px;
    }
    .stat-label {
      font-size: 1rem;
      color: #bfdbfe;
      font-weight: 500;
    }

    /* 流程步骤 */
    .process-step-item {
      position: relative;
      background: #ffffff;
      padding: 2rem 1.5rem;
      border-radius: var(--radius-lg);
      border: 1px solid var(--border-color);
      height: 100%;
    }
    .step-idx {
      width: 36px;
      height: 36px;
      background: var(--primary);
      color: #fff;
      font-weight: 700;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 0.95rem;
      margin-bottom: 1.25rem;
    }

    /* 资讯卡片与手风琴 */
    .news-card-img-wrapper {
      height: 180px;
      overflow: hidden;
      border-radius: var(--radius-md);
      margin-bottom: 1.25rem;
    }
    .news-card-img-wrapper img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      transition: var(--transition);
    }
    .app-card:hover .news-card-img-wrapper img {
      transform: scale(1.05);
    }
    .accordion-item {
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md) !important;
      margin-bottom: 1rem;
      overflow: hidden;
      box-shadow: var(--shadow-sm);
    }
    .accordion-button {
      font-size: 1.05rem;
      font-weight: 600;
      color: var(--text-main);
      padding: 1.25rem 1.5rem;
      background-color: #ffffff;
    }
    .accordion-button:not(.collapsed) {
      background-color: #eff6ff;
      color: var(--primary);
      box-shadow: none;
    }
    .accordion-button:focus {
      box-shadow: none;
      border-color: rgba(29, 78, 216, 0.25);
    }
    .accordion-body {
      padding: 1.25rem 1.5rem;
      color: var(--text-muted);
      line-height: 1.75;
      font-size: 0.95rem;
    }

    /* 页脚 */
    .app-footer {
      background: #0b1120;
      color: #94a3b8;
      padding: 4.5rem 0 2rem;
      border-top: 1px solid #1e293b;
    }
    .app-footer h5 {
      color: #ffffff;
      font-size: 1.1rem;
      font-weight: 700;
      margin-bottom: 1.25rem;
    }
    .footer-links {
      list-style: none;
      padding: 0;
      margin: 0;
    }
    .footer-links li {
      margin-bottom: 0.75rem;
    }
    .footer-links a:hover {
      color: #ffffff;
      padding-left: 4px;
    }
    .footer-bottom {
      margin-top: 3.5rem;
      padding-top: 2rem;
      border-top: 1px solid #1e293b;
      font-size: 0.85rem;
    }

    /* 响应式断点 */
    @media (max-width: 991.98px) {
      .sidebar-navigation {
        display: none;
      }
      .mobile-header-navbar {
        display: flex;
      }
      .app-main-content {
        margin-left: 0;
        padding-top: 64px;
      }
      .hero-h1 {
        font-size: 2.15rem;
      }
      section {
        padding: 4rem 0;
      }
    }
    @media (max-width: 575.98px) {
      .hero-h1 {
        font-size: 1.85rem;
      }
      .section-title {
        font-size: 1.75rem;
      }
      .stat-number {
        font-size: 2.2rem;
      }
    }