/* roulang page: index */
* {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    :root {
      --primary: #1A3C5E;
      --primary-deep: #0F2A40;
      --accent: #C4924A;
      --accent-hover: #A67732;
      --bg: #F4F6F9;
      --white: #FFFFFF;
      --text: #1E2B3C;
      --text-light: #5F6B7A;
      --border: #E2E8F0;
      --success: #1F7B4D;
      --shadow-sm: 0 4px 20px rgba(0,0,0,0.04), 0 1px 3px rgba(0,0,0,0.02);
      --shadow-hover: 0 12px 28px rgba(0,0,0,0.08);
      --radius: 12px;
      --radius-btn: 8px;
      --transition: 0.25s ease;
      --container: 1280px;
      --nav-width: 280px;
    }
    body {
      font-family: 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
      background-color: var(--bg);
      color: var(--text);
      line-height: 1.75;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }
    h1, h2, h3, h4 {
      font-family: 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
      font-weight: 600;
      letter-spacing: -0.2px;
    }
    .eng, .num {
      font-family: 'Inter', 'SF Pro Text', sans-serif;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition);
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    button, input, textarea {
      font-family: inherit;
      font-size: 16px;
    }
    .container {
      max-width: var(--container);
      margin: 0 auto;
      padding: 0 24px;
    }
    /* 分屏布局 */
    .app-shell {
      display: flex;
      min-height: 100vh;
    }
    /* 左侧导航 */
    .side-nav {
      width: var(--nav-width);
      background-color: var(--primary);
      color: white;
      display: flex;
      flex-direction: column;
      justify-content: space-between;
      position: fixed;
      top: 0;
      left: 0;
      height: 100vh;
      z-index: 100;
      padding: 32px 24px 24px;
      box-shadow: 2px 0 15px rgba(0,0,0,0.05);
    }
    .logo-area {
      margin-bottom: 48px;
    }
    .logo-text {
      font-size: 26px;
      font-weight: 700;
      color: white;
      letter-spacing: 1px;
      line-height: 1.2;
    }
    .logo-sub {
      font-size: 14px;
      color: rgba(255,255,255,0.65);
      margin-top: 4px;
    }
    .nav-links {
      display: flex;
      flex-direction: column;
      gap: 8px;
      flex: 1;
      margin-top: 30px;
    }
    .nav-link {
      color: rgba(255,255,255,0.75);
      padding: 10px 16px;
      border-radius: 6px;
      font-weight: 500;
      font-size: 15px;
      display: flex;
      align-items: center;
      gap: 10px;
      transition: 0.2s;
      position: relative;
    }
    .nav-link:hover {
      color: var(--accent);
      background-color: rgba(255,255,255,0.05);
      transform: translateX(4px);
    }
    .nav-link::before {
      content: '';
      position: absolute;
      left: 0;
      top: 50%;
      transform: translateY(-50%);
      width: 3px;
      height: 0;
      background-color: var(--accent);
      border-radius: 0 3px 3px 0;
      transition: height 0.2s;
    }
    .nav-link:hover::before {
      height: 20px;
    }
    .nav-cta {
      margin-top: auto;
      padding-top: 24px;
    }
    .btn-side {
      background: var(--accent);
      color: white;
      border: none;
      padding: 14px 20px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      width: 100%;
      text-align: center;
      transition: 0.2s;
    }
    .btn-side:hover {
      background: var(--accent-hover);
    }
    /* 右侧内容区 */
    .main-content {
      margin-left: var(--nav-width);
      flex: 1;
      width: calc(100% - var(--nav-width));
    }
    /* Hero */
    .hero {
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      position: relative;
      min-height: 100vh;
      display: flex;
      align-items: center;
      color: white;
    }
    .hero-overlay {
      position: absolute;
      inset: 0;
      background: linear-gradient(90deg, rgba(10,20,35,0.8) 0%, rgba(26,60,94,0.5) 100%);
    }
    .hero-content {
      position: relative;
      z-index: 2;
      max-width: 700px;
      padding: 40px 60px;
    }
    .hero h1 {
      font-size: 48px;
      font-weight: 700;
      line-height: 1.2;
      margin-bottom: 24px;
      color: white;
    }
    .hero .accent-text {
      color: var(--accent);
    }
    .hero-desc {
      font-size: 18px;
      color: rgba(255,255,255,0.75);
      margin-bottom: 36px;
    }
    .btn-group {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--accent);
      color: white;
      border: none;
      padding: 14px 36px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: 0.2s;
      display: inline-block;
    }
    .btn-primary:hover {
      background: var(--accent-hover);
    }
    .btn-outline {
      background: transparent;
      border: 1.5px solid white;
      color: white;
      padding: 14px 36px;
      border-radius: var(--radius-btn);
      font-weight: 600;
    }
    .btn-outline:hover {
      background: white;
      color: var(--primary);
    }
    .section {
      padding: 100px 0;
    }
    .section-title {
      font-size: 32px;
      font-weight: 600;
      margin-bottom: 16px;
    }
    .section-sub {
      color: var(--text-light);
      margin-bottom: 48px;
    }
    /* 价值主张 */
    .value-grid {
      display: flex;
      gap: 40px;
      align-items: center;
    }
    .value-text {
      flex: 1;
    }
    .value-image {
      flex: 1;
      border-radius: var(--radius);
      overflow: hidden;
    }
    /* 能力矩阵 */
    .capabilities-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .cap-card {
      background: var(--white);
      padding: 32px;
      border-radius: var(--radius);
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
    }
    .cap-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    .cap-icon {
      color: var(--accent);
      font-size: 28px;
      margin-bottom: 16px;
    }
    /* 场景交替 */
    .scene-row {
      display: flex;
      gap: 60px;
      align-items: center;
      margin-bottom: 80px;
    }
    .scene-img {
      flex: 1;
      border-radius: var(--radius);
    }
    /* 案例网格 */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 24px;
    }
    .case-card {
      background: var(--white);
      padding: 28px;
      border-radius: var(--radius);
      box-shadow: var(--shadow-sm);
    }
    .case-number {
      font-size: 32px;
      font-weight: 700;
      color: var(--success);
    }
    /* 定价 */
    .pricing-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .price-card {
      background: var(--white);
      padding: 36px 24px;
      border-radius: var(--radius);
      text-align: center;
    }
    /* FAQ */
    .faq-item {
      border-bottom: 1px solid var(--border);
      padding: 20px 0;
    }
    .faq-question {
      font-weight: 600;
      font-size: 18px;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
    }
    .faq-answer {
      color: var(--text-light);
      padding-top: 12px;
      display: none;
    }
    .faq-item.active .faq-answer {
      display: block;
    }
    /* footer */
    .footer {
      background: #0F2A40;
      color: rgba(255,255,255,0.7);
      padding: 60px 0 30px;
    }
    @media (max-width: 1024px) {
      .app-shell {
        flex-direction: column;
      }
      .side-nav {
        position: relative;
        width: 100%;
        height: auto;
        flex-direction: row;
        padding: 16px;
      }
      .main-content {
        margin-left: 0;
        width: 100%;
      }
      .capabilities-grid, .pricing-grid {
        grid-template-columns: 1fr;
      }
    }
    @media (max-width: 768px) {
      .hero h1 { font-size: 32px; }
      .value-grid, .scene-row {
        flex-direction: column;
      }
      .cases-grid {
        grid-template-columns: 1fr;
      }
    }