/* roulang page: index */
/* ========== CSS 自定义属性（设计令牌） ========== */
    :root {
      --primary-deep: #0A0E27;
      --accent-cyan: #00E5FF;
      --accent-orange: #FF6B35;
      --card-bg: #1A1F3A;
      --text-main: #FFFFFF;
      --text-secondary: #B0B5CC;
      --text-muted: #8A8FA8;
      --border-light: rgba(255, 255, 255, 0.08);
      --border-glow: rgba(0, 229, 255, 0.4);
      --glass-bg: rgba(26, 31, 58, 0.6);
      --glass-border: rgba(255, 255, 255, 0.1);
      --glass-hover-border: rgba(255, 255, 255, 0.25);
      --radius-card: 16px;
      --radius-btn: 8px;
      --shadow-card: 0 8px 32px rgba(0, 0, 0, 0.4);
      --shadow-glow: 0 0 20px rgba(0, 229, 255, 0.4);
      --shadow-glow-hover: 0 0 30px rgba(0, 229, 255, 0.6);
      --transition-smooth: 0.3s ease;
      --container-max: 1200px;
      --nav-height: 64px;
    }

    /* ========== 全局重置 ========== */
    *, *::before, *::after {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }

    html {
      scroll-behavior: smooth;
      font-size: 16px;
    }

    body {
      font-family: system-ui, -apple-system, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
      background-color: var(--primary-deep);
      color: var(--text-main);
      line-height: 1.7;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }

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

    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition-smooth);
    }

    ul {
      list-style: none;
    }

    /* ========== 容器与布局工具 ========== */
    .container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
    }

    @media (max-width: 768px) {
      .container {
        padding: 0 16px;
      }
    }

    section {
      padding: 100px 0;
    }

    @media (max-width: 768px) {
      section {
        padding: 70px 0;
      }
    }

    /* ========== 导航组件 (固定顶部沉浸式) ========== */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--nav-height);
      background: rgba(10, 14, 39, 0.85);
      backdrop-filter: blur(16px);
      -webkit-backdrop-filter: blur(16px);
      border-bottom: 1px solid var(--border-light);
      z-index: 1000;
      display: flex;
      align-items: center;
    }

    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }

    .logo {
      font-size: 1.5rem;
      font-weight: 700;
      color: var(--accent-cyan);
      letter-spacing: 1px;
      display: flex;
      align-items: center;
      gap: 8px;
    }

    .logo-icon {
      width: 28px;
      height: 28px;
      border: 2px solid var(--accent-cyan);
      border-radius: 6px;
      display: inline-block;
      position: relative;
      background: rgba(0, 229, 255, 0.1);
    }

    .logo-icon::after {
      content: "";
      position: absolute;
      top: 4px;
      left: 4px;
      width: 8px;
      height: 8px;
      background: var(--accent-cyan);
      border-radius: 2px;
    }

    .nav-menu {
      display: flex;
      align-items: center;
      gap: 32px;
    }

    .nav-menu a {
      color: var(--text-secondary);
      font-weight: 500;
      font-size: 0.95rem;
      position: relative;
      padding: 8px 0;
    }

    .nav-menu a:hover,
    .nav-menu a.active {
      color: var(--accent-cyan);
    }

    .nav-menu a::after {
      content: "";
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--accent-cyan);
      transition: width 0.3s ease;
    }

    .nav-menu a:hover::after,
    .nav-menu a.active::after {
      width: 100%;
    }

    .btn-nav {
      background: transparent;
      border: 1px solid var(--accent-cyan);
      color: var(--accent-cyan);
      padding: 8px 20px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: var(--transition-smooth);
      white-space: nowrap;
    }

    .btn-nav:hover {
      background: rgba(0, 229, 255, 0.1);
      box-shadow: var(--shadow-glow);
    }

    /* 移动端汉堡菜单 */
    .menu-toggle {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: transparent;
      border: none;
      padding: 8px;
      z-index: 1001;
    }

    .menu-toggle span {
      width: 24px;
      height: 2px;
      background: var(--text-main);
      transition: 0.3s;
      display: block;
    }

    @media (max-width: 768px) {
      .nav-menu {
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100vh;
        background: rgba(10, 14, 39, 0.95);
        backdrop-filter: blur(20px);
        flex-direction: column;
        justify-content: center;
        align-items: center;
        gap: 40px;
        transform: translateX(100%);
        transition: transform 0.4s ease;
        z-index: 999;
      }

      .nav-menu.open {
        transform: translateX(0);
      }

      .menu-toggle {
        display: flex;
      }

      .btn-nav {
        display: none;
      }
    }

    /* ========== 按钮系统 ========== */
    .btn-primary {
      background: linear-gradient(135deg, #00E5FF, #0088CC);
      color: #fff;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 700;
      border: none;
      cursor: pointer;
      box-shadow: var(--shadow-glow);
      transition: all 0.3s ease;
      display: inline-block;
      text-align: center;
    }

    .btn-primary:hover {
      box-shadow: var(--shadow-glow-hover);
      transform: scale(1.03);
      filter: brightness(1.15);
    }

    .btn-ghost {
      background: transparent;
      border: 1px solid var(--accent-cyan);
      color: var(--accent-cyan);
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: var(--transition-smooth);
      display: inline-block;
      text-align: center;
    }

    .btn-ghost:hover {
      background: rgba(0, 229, 255, 0.1);
    }

    /* ========== 首屏 Hero ========== */
    .hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      position: relative;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      background-blend-mode: overlay;
      background-color: rgba(10, 14, 39, 0.75);
    }

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

    .hero h1 {
      font-size: 3rem;
      font-weight: 700;
      line-height: 1.3;
      margin-bottom: 24px;
      color: var(--text-main);
      text-shadow: 0 0 30px rgba(0, 229, 255, 0.3);
    }

    .hero .subtitle {
      font-size: 1.2rem;
      color: var(--text-secondary);
      margin-bottom: 40px;
      max-width: 550px;
    }

    .hero-buttons {
      display: flex;
      gap: 20px;
      flex-wrap: wrap;
    }

    @media (max-width: 768px) {
      .hero h1 {
        font-size: 2.2rem;
      }
    }

    /* ========== 核心功能 非对称布局 ========== */
    .features-grid {
      display: flex;
      gap: 40px;
      align-items: flex-start;
    }

    .features-left {
      flex: 1;
    }

    .features-right {
      flex: 1;
      background: var(--glass-bg);
      backdrop-filter: blur(12px);
      border: 1px solid var(--glass-border);
      border-radius: var(--radius-card);
      padding: 32px;
      display: flex;
      align-items: center;
      justify-content: center;
      min-height: 400px;
      transition: all 0.4s ease;
    }

    .feature-item {
      display: flex;
      gap: 20px;
      margin-bottom: 40px;
      cursor: pointer;
      padding: 16px;
      border-radius: 12px;
      transition: background 0.2s;
      position: relative;
    }

    .feature-item:hover {
      background: rgba(255,255,255,0.03);
    }

    .feature-icon {
      width: 48px;
      height: 48px;
      border: 2px solid var(--accent-cyan);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--accent-cyan);
      font-size: 1.5rem;
      flex-shrink: 0;
      background: rgba(0,229,255,0.1);
    }

    .feature-text h3 {
      font-size: 1.3rem;
      margin-bottom: 8px;
    }

    .feature-text p {
      color: var(--text-secondary);
    }

    @media (max-width: 768px) {
      .features-grid {
        flex-direction: column;
      }
      .features-right {
        width: 100%;
      }
    }

    /* ========== 场景横向滚动 ========== */
    .scrolling-wrapper {
      display: flex;
      gap: 24px;
      overflow-x: auto;
      padding-bottom: 20px;
      scrollbar-width: none;
      -ms-overflow-style: none;
      mask-image: linear-gradient(to right, black 85%, transparent 100%);
      -webkit-mask-image: linear-gradient(to right, black 85%, transparent 100%);
    }

    .scrolling-wrapper::-webkit-scrollbar {
      display: none;
    }

    .scene-card {
      flex: 0 0 360px;
      background: var(--glass-bg);
      backdrop-filter: blur(12px);
      border: 1px solid var(--glass-border);
      border-radius: var(--radius-card);
      overflow: hidden;
      transition: all 0.3s ease;
    }

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

    .scene-img {
      height: 180px;
      background-size: cover;
      background-position: center;
    }

    .scene-info {
      padding: 20px;
    }

    .scene-info h4 {
      font-size: 1.2rem;
      margin-bottom: 8px;
    }

    @media (max-width: 768px) {
      .scene-card {
        flex: 0 0 80vw;
      }
    }

    /* ========== 数据展示 ========== */
    .stats-grid {
      display: flex;
      justify-content: space-around;
      flex-wrap: wrap;
      gap: 30px;
      margin: 40px 0;
    }

    .stat-item {
      text-align: center;
    }

    .stat-number {
      font-size: 2.8rem;
      font-weight: 700;
      color: var(--accent-cyan);
      font-variant-numeric: tabular-nums;
    }

    /* ========== 套餐卡片 ========== */
    .pricing-grid {
      display: flex;
      gap: 30px;
      justify-content: center;
      flex-wrap: wrap;
    }

    .pricing-card {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      padding: 40px 32px;
      border: 1px solid var(--border-light);
      flex: 1;
      min-width: 260px;
      max-width: 350px;
      transition: all 0.3s;
    }

    .pricing-card.featured {
      border-color: var(--accent-cyan);
      box-shadow: 0 0 25px rgba(0, 229, 255, 0.3);
    }

    .price {
      font-size: 2.5rem;
      font-weight: 700;
      color: var(--accent-orange);
      margin: 20px 0;
    }

    /* ========== FAQ 手风琴 ========== */
    .faq-item {
      border-bottom: 1px solid var(--border-light);
    }

    .faq-question {
      padding: 20px 0;
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      cursor: pointer;
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      color: var(--text-secondary);
      padding-bottom: 0;
    }

    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-bottom: 20px;
    }

    /* ========== 页脚 ========== */
    .footer-cta {
      background: var(--card-bg);
      text-align: center;
      padding: 70px 20px;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 30px;
      padding: 60px 0;
    }

    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr;
      }
    }

    .copyright {
      text-align: center;
      padding: 20px;
      color: var(--text-muted);
      font-size: 0.9rem;
      border-top: 1px solid var(--border-light);
    }