/* roulang page: index */
/* :root 设计变量 */
    :root {
      --primary-deep-purple: #1E0A2E;
      --accent-cyan: #00E5CC;
      --energy-orange: #FF5F1F;
      --bg-warm: #F9F7F4;
      --bg-light-gray: #F5F3F0;
      --text-dark: #333333;
      --text-muted: #777777;
      --border-light: #E8E8E8;
      --card-shadow: 0 4px 12px rgba(0,0,0,0.06);
      --card-hover-shadow: 0 12px 28px rgba(0,0,0,0.12);
      --radius-sm: 4px;
      --radius-md: 8px;
      --radius-lg: 12px;
      --spacing-section: 100px;
      --nav-width: 240px;
      --transition-smooth: 0.3s ease;
    }

    * {
      box-sizing: border-box;
    }

    body {
      font-family: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      background-color: var(--bg-warm);
      color: var(--text-dark);
      line-height: 1.7;
      margin: 0;
      padding: 0;
      overflow-x: hidden;
    }

    /* 左侧竖向导航 (桌面端) */
    .side-nav {
      position: fixed;
      left: 0;
      top: 0;
      width: var(--nav-width);
      height: 100vh;
      background: var(--primary-deep-purple);
      display: flex;
      flex-direction: column;
      padding: 2rem 1.5rem;
      z-index: 100;
      box-shadow: 4px 0 20px rgba(0,0,0,0.2);
      transition: transform 0.3s ease;
    }

    .nav-logo {
      font-size: 1.8rem;
      font-weight: 700;
      color: var(--accent-cyan);
      margin-bottom: 2.5rem;
      letter-spacing: 0.5px;
      display: flex;
      align-items: center;
      gap: 0.5rem;
    }
    .nav-logo i {
      font-size: 2rem;
      color: var(--accent-cyan);
    }

    .nav-links {
      list-style: none;
      margin: 0;
      padding: 0;
      flex: 1;
    }

    .nav-links li {
      margin-bottom: 1.2rem;
    }

    .nav-links a {
      display: block;
      color: rgba(255,255,255,0.7);
      text-decoration: none;
      font-size: 0.95rem;
      font-weight: 400;
      padding: 0.5rem 0.8rem;
      border-radius: var(--radius-sm);
      transition: all var(--transition-smooth);
      position: relative;
    }

    .nav-links a:hover,
    .nav-links a.active {
      color: var(--accent-cyan);
      background: rgba(255,255,255,0.05);
      transform: translateX(6px);
    }

    /* 移动端顶部导航 */
    .mobile-header {
      display: none;
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 56px;
      background: var(--primary-deep-purple);
      z-index: 99;
      align-items: center;
      justify-content: space-between;
      padding: 0 1.5rem;
      box-shadow: 0 2px 10px rgba(0,0,0,0.3);
    }
    .mobile-logo {
      font-size: 1.6rem;
      font-weight: 700;
      color: var(--accent-cyan);
      display: flex;
      align-items: center;
      gap: 0.3rem;
    }
    .hamburger {
      font-size: 1.8rem;
      color: white;
      cursor: pointer;
    }

    /* 右侧主内容区 */
    .main-content {
      margin-left: var(--nav-width);
      width: calc(100% - var(--nav-width));
      background: var(--bg-warm);
    }

    .section-container {
      max-width: 1100px;
      margin: 0 auto;
      padding: 0 2rem;
    }

    section {
      padding: var(--spacing-section) 0;
    }

    /* Hero 区域 */
    .hero-section {
      background: linear-gradient(135deg, #1E0A2E 0%, #0D0418 100%);
      position: relative;
      overflow: hidden;
      padding: 80px 0 100px;
      color: white;
    }
    .hero-particles {
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      pointer-events: none;
    }
    .particle {
      position: absolute;
      background: rgba(0, 229, 204, 0.2);
      border-radius: 50%;
      animation: float 8s infinite ease-in-out;
    }
    @keyframes float {
      0%, 100% { transform: translateY(0px) scale(1); opacity: 0.3; }
      50% { transform: translateY(-20px) scale(1.2); opacity: 0.6; }
    }

    .hero-grid {
      display: grid;
      grid-template-columns: 5fr 7fr;
      gap: 2.5rem;
      align-items: center;
      position: relative;
      z-index: 2;
    }
    .hero-left h1 {
      font-size: 3rem;
      font-weight: 700;
      letter-spacing: -0.5px;
      color: white;
      margin-bottom: 1.2rem;
      line-height: 1.3;
    }
    .hero-left .subtitle {
      font-size: 1.1rem;
      color: rgba(255,255,255,0.8);
      margin-bottom: 2rem;
    }
    .cta-group {
      display: flex;
      gap: 1rem;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--energy-orange);
      color: white;
      border: none;
      padding: 0.8rem 2rem;
      border-radius: var(--radius-md);
      font-weight: 600;
      transition: background var(--transition-smooth);
      text-decoration: none;
      display: inline-block;
    }
    .btn-primary:hover {
      background: #e54d10;
      color: white;
    }
    .btn-outline {
      background: transparent;
      border: 1px solid var(--accent-cyan);
      color: var(--accent-cyan);
      padding: 0.8rem 2rem;
      border-radius: var(--radius-md);
      font-weight: 600;
      transition: all var(--transition-smooth);
      text-decoration: none;
    }
    .btn-outline:hover {
      background: var(--accent-cyan);
      color: #1E0A2E;
    }

    .hero-right img {
      width: 100%;
      border-radius: var(--radius-lg);
      box-shadow: 0 20px 30px rgba(0,0,0,0.5);
      animation: gentleFloat 4s infinite alternate;
    }
    @keyframes gentleFloat {
      from { transform: translateY(0); }
      to { transform: translateY(-10px); }
    }

    /* 标题通用 */
    .section-title {
      font-size: 2.2rem;
      font-weight: 600;
      margin-bottom: 1rem;
      color: #1E0A2E;
      position: relative;
      display: inline-block;
    }
    .section-title::after {
      content: '';
      position: absolute;
      bottom: -8px;
      left: 0;
      width: 60px;
      height: 4px;
      background: var(--accent-cyan);
      border-radius: 2px;
    }

    /* 核心优势 错位布局 */
    .advantage-row {
      display: flex;
      align-items: center;
      gap: 2.5rem;
      margin-bottom: 3rem;
    }
    .advantage-row.reverse {
      flex-direction: row-reverse;
    }
    .adv-text {
      flex: 1;
    }
    .adv-image {
      flex: 1;
      text-align: center;
    }
    .adv-image img {
      max-width: 100%;
      border-radius: var(--radius-md);
      box-shadow: var(--card-shadow);
    }
    .adv-icon {
      font-size: 2.5rem;
      color: var(--accent-cyan);
      margin-bottom: 0.8rem;
    }

    /* 卡片基础 */
    .card {
      background: white;
      border-radius: var(--radius-md);
      border: 1px solid var(--border-light);
      padding: 2rem;
      transition: all var(--transition-smooth);
      box-shadow: var(--card-shadow);
      height: 100%;
    }
    .card:hover {
      transform: translateY(-4px);
      box-shadow: var(--card-hover-shadow);
    }

    /* 功能分组交替背景 */
    .feature-block {
      padding: 3rem 0;
    }
    .bg-light-alt {
      background-color: var(--bg-light-gray);
    }
    .feature-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 2.5rem;
      align-items: center;
    }
    .feature-text ul {
      list-style: none;
      padding-left: 0;
    }
    .feature-text li {
      margin-bottom: 0.8rem;
      display: flex;
      align-items: center;
      gap: 0.6rem;
    }
    .feature-text li i {
      color: var(--accent-cyan);
      font-size: 0.9rem;
    }

    /* 场景卡片 */
    .scene-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 1.8rem;
    }
    .scene-card img {
      width: 100%;
      aspect-ratio: 16/9;
      object-fit: cover;
      border-radius: var(--radius-md) var(--radius-md) 0 0;
      transition: transform 0.4s ease;
    }
    .scene-card:hover img {
      transform: scale(1.03);
    }
    .scene-card .card-content {
      padding: 1.2rem;
    }

    /* 数据面板 */
    .stats-panel {
      display: flex;
      gap: 2rem;
      background: white;
      padding: 2rem;
      border-radius: var(--radius-md);
    }
    .stat-item h3 {
      font-size: 2.5rem;
      font-weight: 700;
      color: var(--energy-orange);
    }

    /* FAQ 手风琴覆盖 */
    .accordion-title {
      font-size: 1rem;
      font-weight: 600;
      color: #1E0A2E;
      border-bottom: 1px solid var(--border-light);
    }
    .accordion-title::before {
      color: var(--accent-cyan);
    }

    /* CTA 横幅 */
    .cta-banner {
      background: linear-gradient(135deg, #1E0A2E, #2a1140);
      border-radius: var(--radius-lg);
      padding: 3rem 2rem;
      text-align: center;
      color: white;
    }

    /* 页脚 */
    .footer {
      background: var(--primary-deep-purple);
      color: rgba(255,255,255,0.7);
      padding: 3rem 0 1.5rem;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 2rem;
    }

    /* 响应式 */
    @media (max-width: 1024px) {
      .hero-grid {
        grid-template-columns: 1fr;
      }
      .hero-right {
        order: -1;
      }
      .feature-grid {
        grid-template-columns: 1fr;
      }
      .scene-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
    }

    @media (max-width: 768px) {
      .side-nav {
        display: none;
      }
      .mobile-header {
        display: flex;
      }
      .main-content {
        margin-left: 0;
        width: 100%;
        margin-top: 56px;
      }
      h1 {
        font-size: 2rem !important;
      }
      .section-title {
        font-size: 1.8rem;
      }
      section {
        padding: 60px 0;
      }
      .advantage-row, .advantage-row.reverse {
        flex-direction: column;
      }
      .scene-grid {
        grid-template-columns: 1fr;
      }
      .stats-panel {
        flex-direction: column;
      }
    }