/* roulang page: index */
/* ----- 设计变量 & 重置 ----- */
    :root {
      --bg-deep: #0A0E1A;
      --bg-panel: #0F1626;
      --card-glass: rgba(30, 41, 59, 0.7);
      --border-glass: rgba(168, 85, 247, 0.25);
      --primary-purple: #A855F7;
      --accent-green: #34D399;
      --text-light: #F1F5F9;
      --text-muted: #94A3B8;
      --text-dark: #0F172A;
      --card-bg: #1E293B;
      --radius-lg: 24px;
      --radius-md: 16px;
      --radius-sm: 12px;
      --shadow-glow: 0 0 20px rgba(52, 211, 153, 0.4);
      --shadow-purple: 0 0 18px rgba(168, 85, 247, 0.4);
      --font-heading: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      --font-body: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", sans-serif;
      --font-mono: "Inter", "DIN", "SF Mono", "Courier New", monospace;
      --transition: all 0.25s ease;
    }

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

    html {
      scroll-behavior: smooth;
      background-color: var(--bg-deep);
    }

    body {
      font-family: var(--font-body);
      background: linear-gradient(145deg, #0A0E1A 0%, #0F1626 100%);
      color: var(--text-light);
      line-height: 1.5;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }

    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 32px;
    }

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

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

    /* 玻璃拟态卡片基础 */
    .glass-card {
      background: var(--card-glass);
      backdrop-filter: blur(16px);
      -webkit-backdrop-filter: blur(16px);
      border: 1px solid var(--border-glass);
      border-radius: var(--radius-md);
    }

    /* 按钮预设 */
    .btn-primary {
      background: var(--accent-green);
      border: none;
      color: #0A0E1A;
      font-weight: 700;
      padding: 14px 36px;
      border-radius: 40px;
      font-size: 1.1rem;
      letter-spacing: 0.5px;
      box-shadow: var(--shadow-glow);
      cursor: pointer;
      transition: 0.3s ease;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      font-family: var(--font-heading);
      border: 1px solid rgba(255,255,255,0.15);
    }
    .btn-primary:hover {
      box-shadow: 0 0 30px rgba(52, 211, 153, 0.7);
      background: #3ce8a0;
      transform: translateY(-2px);
    }

    .btn-outline {
      background: transparent;
      border: 1.5px solid var(--primary-purple);
      color: var(--primary-purple);
      font-weight: 600;
      padding: 14px 36px;
      border-radius: 40px;
      font-size: 1.1rem;
      backdrop-filter: blur(8px);
      transition: 0.3s;
      cursor: pointer;
      display: inline-flex;
      align-items: center;
      gap: 8px;
    }
    .btn-outline:hover {
      background: rgba(168,85,247,0.18);
      border-color: #c084fc;
      box-shadow: 0 0 18px rgba(168,85,247,0.5);
      color: #e9d5ff;
    }

    section {
      padding: 80px 0;
    }

    /* 导航 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      background: rgba(10, 14, 26, 0.75);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      border-bottom: 1px solid rgba(168, 85, 247, 0.2);
      padding: 14px 0;
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 32px;
    }
    .logo {
      font-family: var(--font-heading);
      font-weight: 800;
      font-size: 1.9rem;
      letter-spacing: 1px;
      background: linear-gradient(to right, #e9d5ff, #A855F7);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }
    .nav-links {
      display: flex;
      gap: 36px;
      align-items: center;
    }
    .nav-links a {
      font-weight: 500;
      color: var(--text-muted);
      font-size: 1rem;
      position: relative;
      padding: 6px 0;
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: white;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -3px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary-purple);
      transition: 0.3s;
    }
    .nav-links a:hover::after {
      width: 100%;
    }

    /* 移动端导航 */
    .mobile-nav {
      display: none;
      position: fixed;
      bottom: 16px;
      left: 10px;
      right: 10px;
      background: rgba(15, 22, 38, 0.9);
      backdrop-filter: blur(25px);
      border-radius: 60px;
      padding: 10px 24px;
      border: 1px solid rgba(168,85,247,0.35);
      justify-content: space-around;
      z-index: 999;
    }
    .mobile-nav a {
      display: flex;
      flex-direction: column;
      align-items: center;
      color: #94A3B8;
      font-size: 0.7rem;
      font-weight: 500;
      transition: 0.2s;
    }
    .mobile-nav a i {
      font-size: 1.4rem;
      margin-bottom: 2px;
    }
    .mobile-nav a.active {
      color: var(--primary-purple);
    }

    /* Hero */
    .hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      position: relative;
      padding-top: 80px;
    }
    .hero::before {
      content: '';
      position: absolute;
      inset: 0;
      background: radial-gradient(circle at 20% 30%, rgba(168,85,247,0.25) 0%, transparent 50%), 
                  linear-gradient(180deg, rgba(10,14,26,0.7) 0%, #0A0E1A 95%);
    }
    .hero-content {
      position: relative;
      z-index: 2;
      max-width: 800px;
    }
    .hero h1 {
      font-size: 3.5rem;
      font-weight: 800;
      line-height: 1.2;
      margin-bottom: 24px;
      background: linear-gradient(to right, #fff, #d8b4fe);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }
    .hero .subtitle {
      font-size: 1.3rem;
      color: #CBD5E1;
      margin-bottom: 40px;
    }
    .hero-buttons {
      display: flex;
      gap: 20px;
      flex-wrap: wrap;
    }

    /* 数据看板 */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .stat-card {
      text-align: center;
      padding: 32px 20px;
    }
    .stat-number {
      font-family: var(--font-mono);
      font-size: 2.9rem;
      font-weight: 700;
      color: var(--accent-green);
      text-shadow: 0 0 12px rgba(52,211,153,0.5);
    }
    .stat-label {
      color: #94A3B8;
      margin-top: 10px;
      font-size: 0.95rem;
    }

    /* 服务矩阵 */
    .service-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .service-card {
      padding: 32px 24px;
      transition: 0.3s;
      background: rgba(30,41,59,0.65);
      backdrop-filter: blur(14px);
      border-radius: 20px;
      border: 1px solid rgba(168,85,247,0.2);
    }
    .service-card:hover {
      border-color: var(--primary-purple);
      box-shadow: 0 0 25px rgba(168,85,247,0.35);
      transform: translateY(-5px);
    }
    .service-icon {
      font-size: 2.3rem;
      color: var(--primary-purple);
      margin-bottom: 18px;
    }

    /* 对比区 */
    .compare-row {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 40px;
      align-items: center;
    }
    .compare-left, .compare-right {
      padding: 32px;
      border-radius: 24px;
    }
    .compare-left {
      background: rgba(30,41,59,0.5);
      border: 1px solid #334155;
    }
    .compare-right {
      background: rgba(52,211,153,0.08);
      border: 1px solid var(--accent-green);
    }

    /* FAQ */
    .faq-item {
      border-bottom: 1px solid rgba(168,85,247,0.2);
      padding: 22px 0;
      cursor: pointer;
    }
    .faq-question {
      display: flex;
      justify-content: space-between;
      font-weight: 600;
      font-size: 1.15rem;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: 0.4s ease;
      color: #CBD5E1;
      margin-top: 0;
    }
    .faq-item.active .faq-answer {
      max-height: 160px;
      margin-top: 16px;
    }

    /* CTA */
    .cta-section {
      background: radial-gradient(circle at 30% 40%, #1e1b4b, #0A0E1A);
    }

    footer {
      background: #0A0E1A;
      border-top: 1px solid #1e293b;
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1.5fr;
      gap: 40px;
    }

    @media (max-width: 1024px) {
      .container { padding: 0 24px; }
      .hero h1 { font-size: 2.8rem; }
      .service-grid { grid-template-columns: repeat(2, 1fr); }
    }

    @media (max-width: 768px) {
      .desktop-nav { display: none; }
      .mobile-nav { display: flex; }
      section { padding: 60px 0; }
      .hero { text-align: center; }
      .hero-buttons { justify-content: center; }
      .stats-grid { grid-template-columns: 1fr; gap: 20px; }
      .service-grid { grid-template-columns: 1fr; }
      .compare-row { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr; }
      .hero h1 { font-size: 2.4rem; }
    }