/* roulang page: index */
:root {
      --primary-bg: #1A0B2E;
      --deep-bg: #0D0618;
      --card-bg: #23153C;
      --accent-cyan: #00F0FF;
      --accent-magenta: #FF007A;
      --text-primary: #F0E6FF;
      --text-secondary: #A89BBF;
      --border-glow: rgba(0, 240, 255, 0.15);
      --border-hover-glow: rgba(0, 240, 255, 0.6);
      --shadow-neon: 0 8px 32px rgba(0, 240, 255, 0.15);
      --shadow-magenta: 0 10px 30px -10px rgba(255, 0, 122, 0.2);
      --radius-card: 16px;
      --radius-btn: 8px;
      --font-sans: "Inter", "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "WenQuanYi Micro Hei", sans-serif;
      --transition-smooth: all 0.3s ease;
      --gradient-main: linear-gradient(135deg, #00F0FF 0%, #FF007A 100%);
    }

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

    body {
      font-family: var(--font-sans);
      background-color: var(--deep-bg);
      color: var(--text-primary);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }

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

    h1, h2, h3, h4 {
      font-weight: 600;
      line-height: 1.3;
    }

    h1 {
      font-size: clamp(42px, 8vw, 64px);
      font-weight: 700;
      background: var(--gradient-main);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      margin-bottom: 1.2rem;
      letter-spacing: -0.5px;
    }

    h2 {
      font-size: clamp(32px, 6vw, 44px);
      color: var(--text-primary);
      margin-bottom: 1rem;
      position: relative;
      display: inline-block;
    }

    h2::after {
      content: '';
      position: absolute;
      left: 0;
      bottom: -10px;
      width: 60px;
      height: 4px;
      background: var(--gradient-main);
      border-radius: 2px;
      box-shadow: 0 0 15px var(--accent-cyan);
    }

    h3 {
      font-size: clamp(20px, 3vw, 24px);
      color: var(--text-primary);
      margin-bottom: 0.75rem;
    }

    p, .text-secondary {
      color: var(--text-secondary);
      font-size: 16px;
      line-height: 1.7;
    }

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

    a:hover {
      color: var(--accent-magenta);
    }

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

    button, .btn {
      cursor: pointer;
      font-family: var(--font-sans);
      font-weight: 500;
      font-size: 15px;
      letter-spacing: 0.5px;
      border: none;
      outline: none;
      transition: var(--transition-smooth);
    }

    /* 导航栏 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: rgba(26, 11, 46, 0.85);
      backdrop-filter: blur(12px);
      z-index: 1000;
      border-bottom: 1px solid var(--border-glow);
      box-shadow: 0 4px 20px rgba(0, 0, 0, 0.4);
    }

    .nav {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
    }

    .logo {
      font-size: 28px;
      font-weight: 700;
      background: var(--gradient-main);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      letter-spacing: 1px;
      display: flex;
      align-items: center;
      gap: 8px;
    }

    .logo-icon {
      font-size: 32px;
      filter: drop-shadow(0 0 8px var(--accent-cyan));
    }

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

    .nav-links a {
      color: var(--text-secondary);
      font-weight: 500;
      font-size: 15px;
      position: relative;
      padding: 8px 0;
      transition: var(--transition-smooth);
    }

    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--accent-cyan);
      box-shadow: 0 0 12px var(--accent-cyan);
      transition: width 0.25s ease;
    }

    .nav-links a:hover {
      color: var(--accent-cyan);
    }

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

    .nav-links a.active {
      color: var(--accent-cyan);
    }

    .btn-primary {
      background: var(--gradient-main);
      color: white;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      box-shadow: 0 4px 15px rgba(0, 240, 255, 0.4);
      font-weight: 600;
      border: none;
    }

    .btn-primary:hover {
      filter: brightness(1.2);
      box-shadow: 0 6px 20px rgba(0, 240, 255, 0.7);
      transform: translateY(-1px);
    }

    .btn-outline {
      background: transparent;
      border: 1px solid var(--accent-cyan);
      color: var(--accent-cyan);
      padding: 12px 28px;
      border-radius: var(--radius-btn);
    }

    .btn-outline:hover {
      background: rgba(0, 240, 255, 0.1);
      box-shadow: 0 0 18px rgba(0, 240, 255, 0.5);
    }

    .menu-toggle {
      display: none;
      flex-direction: column;
      gap: 5px;
      background: transparent;
      border: none;
      cursor: pointer;
      padding: 8px;
    }

    .menu-toggle span {
      width: 26px;
      height: 2px;
      background: var(--accent-cyan);
      box-shadow: 0 0 6px var(--accent-cyan);
      transition: var(--transition-smooth);
    }

    /* Hero */
    .hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      position: relative;
      margin-top: 0;
      padding: 120px 0 80px;
    }

    .hero::before {
      content: '';
      position: absolute;
      inset: 0;
      background: radial-gradient(circle at 30% 40%, rgba(0,240,255,0.15) 0%, rgba(13,6,24,0.85) 80%);
    }

    .hero-content {
      position: relative;
      z-index: 2;
      max-width: 800px;
    }

    .hero-subtitle {
      font-size: 20px;
      color: var(--text-secondary);
      margin-bottom: 2rem;
      max-width: 600px;
    }

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

    /* 区块通用 */
    section {
      padding: 100px 0;
    }

    .section-title {
      text-align: center;
      margin-bottom: 60px;
    }

    .section-title h2 {
      display: inline-block;
    }

    /* 服务卡片 交错布局 */
    .services-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 32px;
      margin-top: 20px;
    }

    .service-card {
      background: var(--card-bg);
      border: 1px solid var(--border-glow);
      border-radius: var(--radius-card);
      padding: 32px 24px;
      text-align: center;
      transition: var(--transition-smooth);
    }

    .service-card:hover {
      border-color: var(--border-hover-glow);
      box-shadow: var(--shadow-neon);
      transform: translateY(-6px);
    }

    .service-icon {
      font-size: 48px;
      margin-bottom: 24px;
      display: inline-block;
      background: var(--gradient-main);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }

    /* 优势数据 */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 32px;
      text-align: center;
    }

    .stat-number {
      font-size: 48px;
      font-weight: 700;
      background: var(--gradient-main);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      line-height: 1.2;
    }

    .stat-label {
      color: var(--text-secondary);
      font-size: 16px;
      margin-top: 8px;
    }

    /* 案例 */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 32px;
    }

    .case-card {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      overflow: hidden;
      border: 1px solid var(--border-glow);
      transition: var(--transition-smooth);
    }

    .case-card:hover {
      border-color: var(--border-hover-glow);
      box-shadow: var(--shadow-neon);
      transform: translateY(-5px);
    }

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

    .case-content {
      padding: 24px;
    }

    .tag {
      display: inline-block;
      background: rgba(255, 0, 122, 0.2);
      color: var(--accent-magenta);
      font-size: 13px;
      padding: 4px 12px;
      border-radius: 20px;
      margin-right: 8px;
      margin-bottom: 12px;
    }

    /* 解决方案流程 */
    .steps-container {
      display: flex;
      justify-content: space-between;
      gap: 24px;
    }

    .step {
      flex: 1;
      text-align: center;
      padding: 24px;
      background: var(--card-bg);
      border-radius: var(--radius-card);
      border: 1px solid var(--border-glow);
      transition: var(--transition-smooth);
    }

    .step:hover {
      border-color: var(--accent-cyan);
      box-shadow: var(--shadow-neon);
    }

    .step-number {
      font-size: 40px;
      font-weight: 700;
      background: var(--gradient-main);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }

    /* FAQ */
    .faq-item {
      border-bottom: 1px solid rgba(0, 240, 255, 0.2);
      margin-bottom: 8px;
    }

    .faq-question {
      width: 100%;
      background: transparent;
      border: none;
      color: var(--text-primary);
      font-size: 18px;
      font-weight: 500;
      padding: 24px 0;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      text-align: left;
    }

    .faq-icon {
      font-size: 22px;
      color: var(--accent-cyan);
      transition: transform 0.2s;
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease;
      color: var(--text-secondary);
      padding: 0 0 0 8px;
    }

    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-bottom: 24px;
    }

    .faq-item.active .faq-icon {
      transform: rotate(45deg);
    }

    /* CTA */
    .cta-section {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      padding: 80px 40px;
      text-align: center;
      margin: 0 24px;
    }

    /* 页脚 */
    .footer {
      background: var(--deep-bg);
      padding: 80px 0 30px;
      border-top: 1px solid var(--border-glow);
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }

    .footer-links h4 {
      color: var(--text-primary);
      margin-bottom: 20px;
    }

    .footer-links ul {
      list-style: none;
    }

    .footer-links li {
      margin-bottom: 12px;
    }

    .footer-links a {
      color: var(--text-secondary);
      font-size: 15px;
    }

    .copyright {
      margin-top: 60px;
      text-align: center;
      color: var(--text-secondary);
      font-size: 14px;
    }

    @media (max-width: 1024px) {
      .services-grid, .cases-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .stats-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .steps-container {
        flex-wrap: wrap;
      }
    }

    @media (max-width: 768px) {
      .nav-links {
        display: none;
        position: fixed;
        top: 72px;
        left: 0;
        width: 100%;
        background: rgba(13, 6, 24, 0.96);
        flex-direction: column;
        padding: 32px;
        gap: 28px;
        backdrop-filter: blur(20px);
      }
      .nav-links.active {
        display: flex;
      }
      .menu-toggle {
        display: flex;
      }
      .services-grid, .cases-grid, .stats-grid {
        grid-template-columns: 1fr;
      }
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
      .hero {
        padding: 100px 0 60px;
      }
    }