/* roulang page: index */
/* ----- 设计变量与基础重置 ----- */
    :root {
      --primary-deep: #0A1628;
      --primary-accent: #00E5FF;
      --gold-amber: #F59E0B;
      --card-bg: rgba(15, 30, 55, 0.65);
      --text-main: #E0E6F0;
      --text-secondary: #8899B4;
      --glass-border: rgba(0, 229, 255, 0.18);
      --glow-cyan: 0 0 24px rgba(0, 229, 255, 0.35);
      --card-shadow: 0 8px 32px rgba(0,0,0,0.4), 0 0 0 1px rgba(0,229,255,0.08);
      --radius-card: 16px;
      --radius-btn: 12px;
      --transition-smooth: 0.3s cubic-bezier(0.2, 0.9, 0.4, 1);
      --font-title: 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', sans-serif;
      --font-number: 'Inter', 'SF Pro Display', sans-serif;
    }

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

    body {
      font-family: var(--font-title);
      background: linear-gradient(135deg, #0A1628 0%, #0F1E3A 50%, #0A1628 100%);
      color: var(--text-main);
      line-height: 1.75;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }

    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 基础元素 */
    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    button, .btn {
      cursor: pointer;
      font-family: inherit;
      transition: var(--transition-smooth);
      border: none;
      background: transparent;
    }
    h1, h2, h3 {
      font-weight: 700;
      line-height: 1.3;
    }
    h1 { font-size: 56px; letter-spacing: -1px; }
    h2 { font-size: 40px; }
    h3 { font-size: 24px; font-weight: 600; }
    p { color: var(--text-secondary); }

    /* 按钮系统 */
    .btn-primary {
      background: var(--primary-accent);
      color: var(--primary-deep);
      font-weight: 600;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      box-shadow: var(--glow-cyan);
      display: inline-flex;
      align-items: center;
      gap: 8px;
      letter-spacing: 0.5px;
    }
    .btn-primary:hover {
      box-shadow: 0 0 36px rgba(0, 229, 255, 0.55);
      transform: scale(1.03);
      background: #33EAFF;
    }
    .btn-outline {
      background: transparent;
      border: 1px solid var(--primary-accent);
      color: var(--primary-accent);
      font-weight: 600;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      display: inline-flex;
      align-items: center;
      gap: 8px;
    }
    .btn-outline:hover {
      background: rgba(0, 229, 255, 0.1);
      border-color: #33EAFF;
    }
    .btn-ghost {
      border: 1px solid rgba(255,255,255,0.5);
      color: white;
      background: transparent;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
    }
    .btn-ghost:hover {
      border-color: var(--primary-accent);
      color: var(--primary-accent);
    }

    /* 玻璃拟态卡片 */
    .glass-card {
      background: var(--card-bg);
      backdrop-filter: blur(18px);
      border: 1px solid var(--glass-border);
      border-radius: var(--radius-card);
      box-shadow: var(--card-shadow);
      transition: var(--transition-smooth);
    }
    .glass-card:hover {
      transform: translateY(-4px);
      border-color: rgba(0, 229, 255, 0.4);
      box-shadow: 0 12px 36px rgba(0,0,0,0.5), 0 0 0 1px rgba(0,229,255,0.25);
    }

    /* 区块间距 */
    section {
      padding: 100px 0;
    }

    /* ----- 导航栏 ----- */
    .main-header {
      position: sticky;
      top: 0;
      z-index: 100;
      background: rgba(10, 22, 40, 0.8);
      backdrop-filter: blur(20px);
      border-bottom: 1px solid rgba(0, 229, 255, 0.15);
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
    }
    .logo {
      font-size: 28px;
      font-weight: 700;
      color: white;
      letter-spacing: 2px;
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .logo i {
      color: var(--primary-accent);
      font-size: 32px;
    }
    .nav-links {
      display: flex;
      gap: 36px;
      align-items: center;
      font-weight: 500;
      color: var(--text-secondary);
    }
    .nav-links a {
      position: relative;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary-accent);
      transition: width 0.25s;
    }
    .nav-links a:hover, .nav-links a.active {
      color: var(--primary-accent);
    }
    .nav-links a:hover::after, .nav-links a.active::after {
      width: 100%;
    }
    .hamburger {
      display: none;
      font-size: 28px;
      color: white;
      cursor: pointer;
    }
    .mobile-menu {
      display: none;
    }

    /* Hero 区域 */
    .hero {
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 40px;
      min-height: 85vh;
      position: relative;
      overflow: hidden;
    }
    .hero-content {
      flex: 1;
    }
    .hero-content h1 {
      margin-bottom: 20px;
      background: linear-gradient(to right, #fff, #b0e0ff);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }
    .hero-sub {
      font-size: 20px;
      color: var(--text-secondary);
      margin-bottom: 36px;
      max-width: 480px;
    }
    .hero-actions {
      display: flex;
      gap: 20px;
      flex-wrap: wrap;
      margin-bottom: 48px;
    }
    .trust-badges {
      display: flex;
      gap: 32px;
      color: var(--text-secondary);
      font-size: 14px;
      align-items: center;
      opacity: 0.8;
    }
    .hero-visual {
      flex: 1;
      position: relative;
      display: flex;
      justify-content: center;
    }
    .hero-visual img {
      border-radius: 24px;
      box-shadow: 0 20px 50px rgba(0,0,0,0.6);
      border: 1px solid rgba(255,255,255,0.1);
      max-width: 100%;
    }
    .canvas-bg {
      position: absolute;
      top: 0; left: 0; width: 100%; height: 100%;
      z-index: 0;
      pointer-events: none;
      opacity: 0.25;
    }
    .hero > * { position: relative; z-index: 2; }

    /* 痛点区 */
    .pain-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .pain-item {
      background: rgba(255,255,255,0.03);
      padding: 28px;
      border-radius: var(--radius-card);
      border-left: 4px solid #b91c1c;
    }
    .pain-item i {
      color: #ef4444;
      font-size: 28px;
      margin-bottom: 12px;
    }

    /* 解决方案卡片 */
    .solution-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .solution-card {
      padding: 32px 24px;
      text-align: left;
    }
    .solution-icon {
      font-size: 40px;
      color: var(--primary-accent);
      margin-bottom: 20px;
    }

    /* 数据区 */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 30px;
      text-align: center;
    }
    .stat-number {
      font-family: var(--font-number);
      font-size: 48px;
      font-weight: 700;
      color: var(--gold-amber);
    }

    /* 证言区 */
    .testimonial-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .testimonial-card {
      padding: 32px;
    }
    .stars {
      color: var(--gold-amber);
      margin: 12px 0;
    }
    .profile {
      display: flex;
      align-items: center;
      gap: 14px;
      margin-top: 20px;
    }
    .avatar {
      width: 48px;
      height: 48px;
      border-radius: 50%;
      background: #1e3a5f;
      object-fit: cover;
    }

    /* FAQ 手风琴 */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      border-bottom: 1px solid rgba(255,255,255,0.1);
      padding: 20px 0;
      cursor: pointer;
      transition: 0.2s;
    }
    .faq-question {
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      font-size: 18px;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      color: var(--text-secondary);
      margin-top: 0;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      margin-top: 12px;
    }
    .faq-item.active .faq-question {
      color: var(--primary-accent);
    }

    /* CTA 终极区 */
    .cta-section {
      background: radial-gradient(circle at center, rgba(0,229,255,0.08) 0%, transparent 70%);
      text-align: center;
    }

    /* 页脚 */
    .main-footer {
      background: #0A1628;
      border-top: 1px solid rgba(255,255,255,0.1);
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }
    .footer-bottom {
      margin-top: 40px;
      padding-top: 20px;
      border-top: 1px solid rgba(255,255,255,0.1);
      display: flex;
      justify-content: space-between;
      color: var(--text-secondary);
      font-size: 14px;
    }

    /* 响应式 */
    @media (max-width: 1024px) {
      h1 { font-size: 44px; }
      h2 { font-size: 34px; }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: block; }
      .hero {
        flex-direction: column;
        text-align: center;
        padding-top: 40px;
      }
      .hero-sub { max-width: 100%; }
      .hero-actions { justify-content: center; }
      .pain-grid, .solution-grid, .testimonial-grid {
        grid-template-columns: 1fr;
      }
      .stats-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
      h1 { font-size: 36px; }
      h2 { font-size: 28px; }
    }
    @media (max-width: 480px) {
      .stats-grid, .footer-grid {
        grid-template-columns: 1fr;
      }
      .hero-actions {
        flex-direction: column;
        align-items: center;
      }
    }

    /* 移动端菜单面板 */
    .mobile-menu.open {
      display: flex;
      flex-direction: column;
      position: fixed;
      top: 72px;
      left: 0;
      width: 100%;
      height: 100vh;
      background: rgba(10,22,40,0.95);
      backdrop-filter: blur(25px);
      align-items: center;
      justify-content: center;
      gap: 32px;
      font-size: 22px;
      z-index: 99;
    }