/* roulang page: index */
:root {
      --primary-deep-purple: #1A0B2E;
      --primary-dark-bg: #0D0618;
      --accent-gold: #D4AF37;
      --neon-cyan: #00F0FF;
      --text-white: #FFFFFF;
      --text-light-gray: #B0B0C0;
      --text-muted: #7A7A8A;
      --glass-bg: rgba(255, 255, 255, 0.03);
      --glass-border: rgba(212, 175, 55, 0.15);
      --glass-border-hover: rgba(0, 240, 255, 0.3);
      --card-shadow: 0 8px 32px rgba(0, 240, 255, 0.08);
      --button-glow: 0 0 20px rgba(0, 240, 255, 0.4);
      --font-sans: "PingFang SC", "Microsoft YaHei", "Inter", sans-serif;
      --font-mono: "Rajdhani", "Inter", sans-serif;
      --radius-card: 16px;
      --radius-button: 50px;
      --radius-input: 8px;
      --radius-nav: 100px;
      --transition-smooth: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
    }

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

    body {
      font-family: var(--font-sans);
      background: linear-gradient(160deg, var(--primary-deep-purple) 0%, var(--primary-dark-bg) 100%);
      color: var(--text-light-gray);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
      background-attachment: fixed;
    }

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

    /* 导航栏 - 悬浮胶囊 */
    .nav-bar {
      position: fixed;
      top: 24px;
      left: 50%;
      transform: translateX(-50%);
      width: calc(100% - 64px);
      max-width: 1200px;
      background: rgba(13, 6, 24, 0.75);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      border-radius: var(--radius-nav);
      padding: 16px 32px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      z-index: 1000;
      border: 1px solid rgba(212, 175, 55, 0.18);
      box-shadow: 0 8px 30px rgba(0, 0, 0, 0.5);
      transition: background var(--transition-smooth);
    }

    .logo {
      font-size: 1.8rem;
      font-weight: 800;
      letter-spacing: 1px;
      background: linear-gradient(135deg, var(--accent-gold), #F5E7A7);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      display: flex;
      align-items: center;
      gap: 8px;
      white-space: nowrap;
    }
    .logo i {
      background: none;
      -webkit-text-fill-color: var(--neon-cyan);
      font-size: 2rem;
      text-shadow: 0 0 15px var(--neon-cyan);
    }
    .nav-links {
      display: flex;
      gap: 28px;
      align-items: center;
      list-style: none;
    }
    .nav-links a {
      color: var(--text-light-gray);
      text-decoration: none;
      font-weight: 500;
      font-size: 1rem;
      transition: color var(--transition-smooth), text-shadow var(--transition-smooth);
      padding: 8px 0;
      position: relative;
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: var(--accent-gold);
      text-shadow: 0 0 10px rgba(212, 175, 55, 0.5);
    }
    .cta-nav {
      background: var(--neon-cyan);
      color: var(--primary-deep-purple) !important;
      font-weight: 700;
      padding: 10px 24px !important;
      border-radius: var(--radius-button);
      box-shadow: var(--button-glow);
      transition: all var(--transition-smooth);
      text-shadow: none !important;
    }
    .cta-nav:hover {
      background: #33F5FF;
      box-shadow: 0 0 30px rgba(0, 240, 255, 0.7);
      transform: scale(1.02);
    }
    .menu-toggle {
      display: none;
      background: transparent;
      border: none;
      color: var(--text-white);
      font-size: 2rem;
      cursor: pointer;
    }

    /* 通用区块 */
    section {
      padding: 100px 0;
      position: relative;
    }
    .section-title {
      font-size: 2.5rem;
      font-weight: 700;
      color: var(--text-white);
      margin-bottom: 16px;
      text-align: center;
    }
    .section-subtitle {
      color: var(--text-light-gray);
      text-align: center;
      max-width: 700px;
      margin: 0 auto 60px;
      font-size: 1.1rem;
    }

    /* Hero */
    .hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      padding-top: 140px;
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 60px;
      align-items: center;
    }
    .hero-left h1 {
      font-size: 3.5rem;
      font-weight: 800;
      line-height: 1.2;
      background: linear-gradient(to right, #F5E7A7, var(--accent-gold));
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      margin-bottom: 24px;
    }
    .hero-highlight {
      color: var(--text-white);
      font-size: 1.4rem;
      font-weight: 600;
      margin-bottom: 20px;
    }
    .hero-desc {
      color: var(--text-light-gray);
      margin-bottom: 40px;
      font-size: 1.1rem;
    }
    .hero-buttons {
      display: flex;
      gap: 20px;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--neon-cyan);
      color: var(--primary-deep-purple);
      font-weight: 700;
      padding: 14px 32px;
      border-radius: var(--radius-button);
      border: none;
      cursor: pointer;
      box-shadow: var(--button-glow);
      transition: all var(--transition-smooth);
      text-decoration: none;
      display: inline-block;
      font-size: 1rem;
    }
    .btn-primary:hover {
      background: #33F5FF;
      box-shadow: 0 0 35px rgba(0, 240, 255, 0.8);
      transform: translateY(-2px);
    }
    .btn-ghost {
      background: transparent;
      border: 1px solid var(--accent-gold);
      color: var(--accent-gold);
      padding: 14px 32px;
      border-radius: var(--radius-button);
      font-weight: 600;
      transition: all var(--transition-smooth);
      text-decoration: none;
      display: inline-block;
    }
    .btn-ghost:hover {
      border-color: white;
      background: rgba(255,255,255,0.08);
      color: white;
    }
    .hero-image-card {
      background: rgba(20, 10, 35, 0.5);
      backdrop-filter: blur(12px);
      border: 1px solid rgba(0, 240, 255, 0.2);
      border-radius: 24px;
      overflow: hidden;
      box-shadow: 0 0 40px rgba(0, 240, 255, 0.2);
      position: relative;
    }
    .hero-image-card img {
      width: 100%;
      height: auto;
      display: block;
      object-fit: cover;
    }

    /* 服务卡片 */
    .cards-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 30px;
    }
    .service-card {
      background: var(--glass-bg);
      backdrop-filter: blur(12px);
      border: 1px solid var(--glass-border);
      border-radius: var(--radius-card);
      padding: 32px 24px;
      transition: all var(--transition-smooth);
      box-shadow: var(--card-shadow);
    }
    .service-card:hover {
      transform: translateY(-10px);
      border-color: var(--glass-border-hover);
      box-shadow: 0 15px 35px rgba(0, 240, 255, 0.25);
    }
    .service-icon {
      font-size: 2.5rem;
      color: var(--neon-cyan);
      margin-bottom: 20px;
    }
    .service-card h3 {
      color: white;
      margin-bottom: 12px;
    }

    /* 数据优势 */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 30px;
      text-align: center;
    }
    .stat-item .stat-number {
      font-family: var(--font-mono);
      font-size: 3.2rem;
      font-weight: 700;
      background: linear-gradient(180deg, var(--neon-cyan), var(--accent-gold));
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }
    .stat-label {
      color: var(--text-light-gray);
      margin-top: 8px;
    }

    /* 案例卡片 */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 30px;
    }
    .case-card {
      background: rgba(255,255,255,0.02);
      border-radius: var(--radius-card);
      overflow: hidden;
      transition: all var(--transition-smooth);
      border: 1px solid transparent;
    }
    .case-card:hover {
      transform: translateY(-8px);
      border-color: var(--neon-cyan);
    }
    .case-img {
      position: relative;
      overflow: hidden;
    }
    .case-img img {
      width: 100%;
      display: block;
      transition: transform 0.4s;
    }
    .case-card:hover .case-img img {
      transform: scale(1.05);
    }
    .case-info {
      padding: 20px;
      background: rgba(0,0,0,0.4);
    }

    /* 解决方案交替 */
    .solution-row {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 60px;
      align-items: center;
      margin-bottom: 80px;
    }
    .solution-img {
      background: rgba(0,240,255,0.05);
      border-radius: 24px;
      padding: 20px;
      border: 1px solid rgba(212,175,55,0.2);
    }

    /* FAQ */
    .faq-item {
      background: rgba(255,255,255,0.03);
      border-radius: 12px;
      margin-bottom: 16px;
      border-left: 4px solid #555;
      transition: all var(--transition-smooth);
      cursor: pointer;
      padding: 20px;
    }
    .faq-item.active {
      border-left-color: var(--neon-cyan);
      box-shadow: 0 0 20px rgba(0,240,255,0.15);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      color: #ccc;
    }

    /* CTA */
    .cta-section {
      background: radial-gradient(circle at center, rgba(0,240,255,0.08) 0%, transparent 70%);
    }

    footer {
      background: #0A0414;
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }

    @media (max-width: 1024px) {
      .hero-grid, .solution-row { grid-template-columns: 1fr; }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .menu-toggle { display: block; }
      .cards-grid, .cases-grid { grid-template-columns: 1fr; }
      .stats-grid { grid-template-columns: 1fr 1fr; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }
    @media (max-width: 520px) {
      .stats-grid, .footer-grid { grid-template-columns: 1fr; }
    }