/* roulang page: index */
/* ----- 设计变量与基础重置 ----- */
    :root {
      --deep-ocean: #0B1E3C;
      --dark-ocean: #0D2B56;
      --coral-orange: #FF6B4A;
      --coral-hover: #E85D3A;
      --whale-white: #F0F4F8;
      --card-bg: #FFFFFF;
      --text-dark: #1A2A3A;
      --text-white: #FFFFFF;
      --ice-blue: #D6E2EC;
      --footer-bg: #0A182F;
      --footer-text: #8899AA;
      --shadow-sm: 0 4px 20px rgba(11, 30, 60, 0.08);
      --shadow-hover: 0 8px 30px rgba(11, 30, 60, 0.15);
      --border-radius-card: 16px;
      --border-radius-btn: 8px;
      --border-radius-lg: 20px;
      --font-sans: 'Inter', 'PingFang SC', 'Microsoft YaHei', 'Hiragino Sans GB', sans-serif;
      --transition-smooth: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
      --nav-width: 220px;
    }

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

    body {
      font-family: var(--font-sans);
      background-color: #FFFFFF;
      color: var(--text-dark);
      line-height: 1.7;
      font-size: 16px;
      display: flex;
      flex-direction: column;
      min-height: 100vh;
    }

    /* 桌面端左侧导航布局 */
    .app-wrapper {
      display: flex;
      flex: 1;
      width: 100%;
    }

    /* ----- 左侧竖向导航（桌面端） ----- */
    .side-nav {
      width: var(--nav-width);
      height: 100vh;
      position: fixed;
      left: 0;
      top: 0;
      background-color: var(--deep-ocean);
      display: flex;
      flex-direction: column;
      z-index: 1000;
      box-shadow: 2px 0 15px rgba(0,0,0,0.2);
      transition: transform 0.3s ease;
    }

    .nav-brand {
      padding: 28px 20px 20px;
      border-bottom: 1px solid rgba(255,255,255,0.1);
      display: flex;
      align-items: center;
      gap: 10px;
      height: 80px;
    }

    .nav-brand i {
      font-size: 32px;
      color: var(--coral-orange);
    }

    .nav-brand span {
      font-size: 22px;
      font-weight: 700;
      color: white;
      letter-spacing: 1px;
    }

    .nav-links {
      flex: 1;
      display: flex;
      flex-direction: column;
      padding: 24px 0;
      list-style: none;
    }

    .nav-links li a {
      display: flex;
      align-items: center;
      padding: 14px 24px;
      color: rgba(255,255,255,0.85);
      text-decoration: none;
      font-weight: 500;
      font-size: 15px;
      transition: var(--transition-smooth);
      border-left: 3px solid transparent;
    }

    .nav-links li a i {
      width: 24px;
      margin-right: 12px;
      font-size: 16px;
      color: rgba(255,255,255,0.7);
      transition: var(--transition-smooth);
    }

    .nav-links li a:hover {
      background-color: rgba(255,255,255,0.05);
      color: var(--coral-orange);
      border-left: 3px solid var(--coral-orange);
    }

    .nav-links li a:hover i {
      color: var(--coral-orange);
    }

    .nav-cta-link a {
      margin: 10px 20px;
      background-color: var(--coral-orange);
      color: white !important;
      border-radius: var(--border-radius-btn);
      justify-content: center;
      padding: 12px;
      font-weight: 600;
      border-left: none !important;
      text-align: center;
    }

    .nav-cta-link a:hover {
      background-color: var(--coral-hover);
      color: white !important;
    }

    .nav-footer {
      padding: 20px;
      font-size: 12px;
      color: rgba(255,255,255,0.5);
      border-top: 1px solid rgba(255,255,255,0.1);
    }

    /* 主内容区域偏移导航宽度 */
    .main-content {
      margin-left: var(--nav-width);
      flex: 1;
      width: calc(100% - var(--nav-width));
    }

    /* 移动端顶部导航（默认隐藏） */
    .mobile-nav {
      display: none;
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 60px;
      background-color: var(--deep-ocean);
      z-index: 1100;
      align-items: center;
      justify-content: space-between;
      padding: 0 20px;
    }

    .mobile-brand {
      display: flex;
      align-items: center;
      gap: 8px;
      color: white;
      font-weight: 700;
      font-size: 20px;
    }

    .hamburger {
      background: none;
      border: none;
      color: white;
      font-size: 24px;
      cursor: pointer;
    }

    .mobile-menu-overlay {
      display: none;
      position: fixed;
      top: 60px;
      left: 0;
      width: 100%;
      height: calc(100vh - 60px);
      background-color: rgba(11, 30, 60, 0.98);
      z-index: 1050;
      flex-direction: column;
      padding: 30px 20px;
      overflow-y: auto;
    }

    .mobile-menu-overlay a {
      color: white;
      font-size: 18px;
      padding: 16px 0;
      border-bottom: 1px solid rgba(255,255,255,0.1);
      text-decoration: none;
      display: flex;
      align-items: center;
      gap: 12px;
    }

    /* 通用容器 */
    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 40px;
    }

    section {
      padding: 80px 0;
      scroll-margin-top: 20px;
    }

    h2 {
      font-size: 36px;
      font-weight: 700;
      line-height: 1.3;
      margin-bottom: 16px;
      color: var(--text-dark);
    }

    .section-subtitle {
      font-size: 18px;
      color: #4a5b6b;
      margin-bottom: 48px;
      max-width: 700px;
    }

    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 14px 32px;
      font-weight: 600;
      font-size: 16px;
      border-radius: var(--border-radius-btn);
      text-decoration: none;
      transition: var(--transition-smooth);
      cursor: pointer;
      border: none;
    }

    .btn-primary {
      background-color: var(--coral-orange);
      color: white;
    }

    .btn-primary:hover {
      background-color: var(--coral-hover);
      transform: scale(1.03);
    }

    .btn-outline {
      border: 2px solid var(--coral-orange);
      color: var(--coral-orange);
      background: transparent;
    }

    .btn-outline:hover {
      background-color: rgba(255,107,74,0.08);
      transform: scale(1.03);
    }

    /* 卡片样式 */
    .card {
      background: var(--card-bg);
      border-radius: var(--border-radius-card);
      padding: 32px;
      box-shadow: var(--shadow-sm);
      transition: var(--transition-smooth);
    }

    .card:hover {
      box-shadow: var(--shadow-hover);
      transform: translateY(-4px);
    }

    /* 响应式规则 */
    @media (max-width: 1024px) {
      .side-nav {
        display: none;
      }
      .mobile-nav {
        display: flex;
      }
      .main-content {
        margin-left: 0;
        width: 100%;
        padding-top: 60px;
      }
      .container {
        padding: 0 24px;
      }
      section {
        padding: 60px 0;
      }
    }

    @media (max-width: 768px) {
      h2 {
        font-size: 28px;
      }
      .container {
        padding: 0 20px;
      }
      .btn {
        width: 100%;
        justify-content: center;
      }
    }

    /* 具体区块样式 */
    .hero-section {
      background: linear-gradient(180deg, #0B1E3C 0%, #0D2B56 100%);
      min-height: 100vh;
      display: flex;
      align-items: center;
      position: relative;
      overflow: hidden;
      color: white;
    }

    .hero-bg-decor {
      position: absolute;
      right: 0;
      bottom: 0;
      width: 50%;
      height: 100%;
      background: url('/assets/images/backpic/back-1.webp') no-repeat center right;
      background-size: cover;
      opacity: 0.25;
      mask-image: radial-gradient(circle at center, black 20%, transparent 80%);
    }

    .hero-content {
      position: relative;
      z-index: 2;
      max-width: 700px;
    }

    .hero-content h1 {
      font-size: 48px;
      font-weight: 800;
      line-height: 1.2;
      margin-bottom: 24px;
    }

    .hero-content p {
      font-size: 18px;
      opacity: 0.9;
      margin-bottom: 40px;
    }

    .pain-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      margin-top: 24px;
    }

    .pain-card i {
      font-size: 28px;
      color: var(--coral-orange);
      margin-bottom: 16px;
    }

    .solutions-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .solution-card img {
      width: 100%;
      height: 140px;
      object-fit: cover;
      border-radius: 12px;
      margin-bottom: 20px;
    }

    .results-section {
      background-color: var(--deep-ocean);
      color: white;
    }

    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 30px;
      text-align: center;
    }

    .stat-number {
      font-size: 48px;
      font-weight: 800;
      color: var(--coral-orange);
    }

    .testimonials-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 24px;
    }

    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }

    .faq-item {
      border-bottom: 1px solid var(--ice-blue);
      padding: 16px 0;
    }

    .faq-question {
      font-weight: 600;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }

    .cta-final {
      background-color: var(--deep-ocean);
      text-align: center;
      color: white;
    }

    footer {
      background-color: var(--footer-bg);
      color: var(--footer-text);
      padding: 60px 0 30px;
    }

    @media (max-width: 768px) {
      .pain-grid, .solutions-grid, .stats-grid, .testimonials-grid {
        grid-template-columns: 1fr;
      }
      .hero-content h1 {
        font-size: 32px;
      }
    }