/* roulang page: index */
/* ----- 设计变量与基础重置 ----- */
    :root {
      --amber-gold: #E89C00;
      --amber-glow: #F0A500;
      --electric-blue: #4F8CFF;
      --deep-bg-start: #0F1722;
      --deep-bg-end: #1A2332;
      --card-bg: rgba(255, 255, 255, 0.04);
      --card-border: rgba(255, 255, 255, 0.08);
      --text-primary: #FFFFFF;
      --text-headline: #F0F4FA;
      --text-body: #B0BEC5;
      --text-muted: #94A3B8;
      --text-label: #64748B;
      --radius-md: 12px;
      --radius-lg: 16px;
      --radius-btn: 8px;
      --shadow-card: 0 8px 32px rgba(0, 0, 0, 0.4);
      --shadow-glow: 0 0 20px rgba(240, 165, 0, 0.5);
      --transition-smooth: 0.25s cubic-bezier(0.2, 0.0, 0, 1.0);
    }

    * {
      box-sizing: border-box;
    }

    body {
      font-family: 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', 'Inter', system-ui, -apple-system, sans-serif;
      background: linear-gradient(135deg, var(--deep-bg-start) 0%, var(--deep-bg-end) 100%);
      color: var(--text-body);
      line-height: 1.7;
      margin: 0;
      padding: 0;
      overflow-x: hidden;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }

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

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

    a:hover {
      color: var(--amber-gold);
    }

    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }

    /* ----- 玻璃拟态卡片基础 ----- */
    .glass-card {
      background: var(--card-bg);
      backdrop-filter: blur(16px);
      -webkit-backdrop-filter: blur(16px);
      border: 1px solid var(--card-border);
      border-radius: var(--radius-lg);
      box-shadow: var(--shadow-card);
      transition: border var(--transition-smooth), box-shadow var(--transition-smooth), transform var(--transition-smooth);
    }

    .glass-card:hover {
      border-color: rgba(240, 165, 0, 0.4);
      box-shadow: 0 12px 40px rgba(240, 165, 0, 0.15);
      transform: translateY(-4px);
    }

    /* ----- 排版层级 ----- */
    h1 {
      font-size: clamp(36px, 5vw, 48px);
      font-weight: 700;
      color: var(--text-primary);
      margin-bottom: 1rem;
      letter-spacing: -0.5px;
    }

    h2 {
      font-size: clamp(28px, 4vw, 36px);
      font-weight: 600;
      color: var(--text-headline);
      margin-bottom: 1.5rem;
    }

    h3 {
      font-size: clamp(18px, 2.5vw, 22px);
      font-weight: 600;
      color: #E2E8F0;
    }

    .section-title {
      position: relative;
      padding-bottom: 0.5rem;
      margin-bottom: 2.5rem;
    }

    .section-title:after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 60px;
      height: 3px;
      background: var(--amber-gold);
      border-radius: 2px;
    }

    /* ----- 按钮系统 ----- */
    .btn-primary {
      background: linear-gradient(135deg, var(--amber-gold), #D48900);
      border: none;
      color: #fff;
      font-weight: 600;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      box-shadow: var(--shadow-glow);
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      transition: all var(--transition-smooth);
      font-size: 1rem;
      cursor: pointer;
      text-transform: none;
      letter-spacing: 0.3px;
      white-space: nowrap;
    }

    .btn-primary:hover {
      background: linear-gradient(135deg, #FBBF24, #E89C00);
      box-shadow: 0 0 28px rgba(240, 165, 0, 0.7);
      transform: scale(1.03);
      color: #fff;
    }

    .btn-ghost {
      background: transparent;
      border: 1.5px solid var(--electric-blue);
      color: #fff;
      font-weight: 600;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      transition: all var(--transition-smooth);
      font-size: 1rem;
      cursor: pointer;
      backdrop-filter: blur(8px);
    }

    .btn-ghost:hover {
      background: rgba(79, 140, 255, 0.12);
      border-color: #80B2FF;
      color: #fff;
      transform: translateY(-2px);
    }

    /* ----- 导航栏 (Foundation 覆盖) ----- */
    .old-sun-nav {
      background: rgba(15, 23, 34, 0.8);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      border-bottom: 1px solid rgba(255, 255, 255, 0.06);
      padding: 0 24px;
      height: 72px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      position: sticky;
      top: 0;
      z-index: 100;
      box-shadow: 0 4px 20px rgba(0,0,0,0.3);
    }

    .logo-area {
      display: flex;
      align-items: center;
      gap: 10px;
      font-weight: 700;
      font-size: 1.5rem;
      color: var(--text-primary);
      white-space: nowrap;
    }

    .logo-icon {
      font-size: 2rem;
      color: var(--amber-gold);
      filter: drop-shadow(0 0 8px rgba(240,165,0,0.6));
    }

    .nav-chips {
      display: flex;
      gap: 8px;
      flex-wrap: wrap;
      justify-content: center;
    }

    .nav-chip {
      background: rgba(255,255,255,0.05);
      color: var(--text-muted);
      padding: 8px 18px;
      border-radius: 40px;
      font-size: 0.9rem;
      font-weight: 500;
      border: 1px solid transparent;
      transition: all var(--transition-smooth);
      white-space: nowrap;
    }

    .nav-chip:hover, .nav-chip.active {
      background: var(--amber-gold);
      color: #0F1722;
      border-color: var(--amber-gold);
      font-weight: 600;
      box-shadow: 0 0 16px rgba(240,165,0,0.5);
    }

    .nav-cta-button {
      background: var(--amber-gold);
      color: #0F1722;
      border: none;
      padding: 10px 24px;
      border-radius: 40px;
      font-weight: 700;
      font-size: 0.95rem;
      box-shadow: 0 0 16px rgba(240,165,0,0.5);
      display: flex;
      align-items: center;
      gap: 6px;
      transition: all var(--transition-smooth);
      white-space: nowrap;
    }

    .nav-cta-button:hover {
      background: #FBBF24;
      box-shadow: 0 0 24px rgba(240,165,0,0.8);
      color: #0F1722;
    }

    /* 汉堡菜单隐藏桌面 */
    .hamburger {
      display: none;
      font-size: 2rem;
      color: #fff;
      cursor: pointer;
    }

    /* ----- Hero 双栏 ----- */
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 60px;
      align-items: center;
      min-height: 80vh;
      padding: 60px 0;
    }

    .hero-left h1 {
      background: linear-gradient(to right, #FFFFFF, #F0A500);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }

    .hero-stats {
      display: flex;
      gap: 30px;
      margin-top: 2rem;
      flex-wrap: wrap;
    }

    .stat-item {
      background: rgba(255,255,255,0.06);
      backdrop-filter: blur(12px);
      padding: 16px 20px;
      border-radius: 12px;
      border-left: 3px solid var(--amber-gold);
    }

    .stat-number {
      font-size: 2rem;
      font-weight: 700;
      color: var(--amber-glow);
    }

    /* ----- 亮点网格 ----- */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
      gap: 30px;
      margin: 50px 0;
    }

    .feature-icon {
      font-size: 2.2rem;
      color: var(--electric-blue);
      margin-bottom: 1rem;
    }

    /* ----- 产品瀑布流 ----- */
    .waterfall-grid {
      columns: 3 280px;
      column-gap: 28px;
    }

    .product-card {
      break-inside: avoid;
      margin-bottom: 28px;
      background: rgba(255,255,255,0.03);
      backdrop-filter: blur(12px);
      border-radius: 20px;
      overflow: hidden;
      border: 1px solid rgba(255,255,255,0.05);
      transition: all 0.3s;
    }

    .product-card:hover {
      border-color: rgba(240,165,0,0.5);
      transform: translateY(-5px);
    }

    .product-img {
      height: 220px;
      object-fit: cover;
      width: 100%;
    }

    .chip-tag {
      background: rgba(15,23,34,0.7);
      border: 1px solid var(--electric-blue);
      color: #B0D4FF;
      padding: 4px 14px;
      border-radius: 30px;
      font-size: 0.8rem;
    }

    /* ----- 案例卡片 ----- */
    .case-card {
      background: rgba(0,0,0,0.3);
      backdrop-filter: blur(10px);
      border-radius: 20px;
      overflow: hidden;
      transition: 0.3s;
    }

    .case-card:hover img {
      transform: scale(1.05);
    }

    /* ----- 解决方案对比 ----- */
    .compare-table {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 30px;
      background: rgba(255,255,255,0.02);
      backdrop-filter: blur(15px);
      border-radius: 24px;
      padding: 2rem;
    }

    .old-sun-highlight {
      border-left: 6px solid var(--amber-gold);
      padding-left: 1.5rem;
    }

    /* ----- FAQ 手风琴 (Foundation 覆盖) ----- */
    .accordion {
      background: transparent;
    }

    .accordion-item {
      background: rgba(255,255,255,0.03);
      backdrop-filter: blur(10px);
      border: 1px solid rgba(255,255,255,0.05);
      border-radius: 16px;
      margin-bottom: 16px;
    }

    .accordion-title {
      font-size: 1.1rem;
      font-weight: 600;
      color: #E2E8F0;
      background: transparent;
      border: none;
      padding: 20px 24px;
      display: flex;
      align-items: center;
      gap: 16px;
      border-left: 4px solid var(--amber-gold);
      transition: 0.3s;
    }

    .accordion-title:hover {
      border-left-color: #FFD966;
    }

    .accordion-content {
      background: rgba(0,0,0,0.2);
      color: #B0BEC5;
      padding: 0 24px 20px;
      border-top: 1px solid rgba(255,255,255,0.05);
    }

    /* ----- CTA 横幅 ----- */
    .cta-banner {
      background: radial-gradient(circle at 30% 50%, rgba(240,165,0,0.15), transparent 60%);
      backdrop-filter: blur(25px);
      border: 1px solid rgba(255,255,255,0.1);
      border-radius: 32px;
      padding: 4rem 2rem;
    }

    /* ----- 页脚 ----- */
    .footer-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 2rem;
      border-top: 1px solid rgba(255,255,255,0.06);
      padding-top: 3rem;
    }

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

    @media (max-width: 768px) {
      .nav-chips, .nav-cta-button {
        display: none;
      }
      .hamburger {
        display: block;
      }
      .waterfall-grid {
        columns: 2;
      }
      .compare-table {
        grid-template-columns: 1fr;
      }
    }

    @media (max-width: 520px) {
      .waterfall-grid {
        columns: 1;
      }
      .footer-grid {
        grid-template-columns: 1fr;
      }
    }

    .off-canvas-menu {
      background: #0F1722;
    }