/* roulang page: index */
/* 设计变量与基础重置 */
    :root {
      --deep-blue: #0A0E27;
      --cyan: #00F0FF;
      --orange-gold: #FF6B35;
      --cold-white: #E8F0FE;
      --grey-blue: #8E9AAF;
      --card-bg: rgba(255,255,255,0.04);
      --card-border: rgba(0,240,255,0.15);
      --glass-blur: blur(16px);
      --radius-card: 16px;
      --radius-btn: 8px;
      --shadow-cyan: 0 8px 32px rgba(0,240,255,0.08);
      --transition-smooth: 0.3s ease-out;
    }
    
    * {
      box-sizing: border-box;
    }
    
    body {
      margin: 0;
      font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      background-color: var(--deep-blue);
      color: var(--cold-white);
      line-height: 1.5;
      -webkit-font-smoothing: antialiased;
    }
    
    /* 自定义滚动条 */
    ::-webkit-scrollbar {
      width: 6px;
    }
    ::-webkit-scrollbar-track {
      background: #0A0E27;
    }
    ::-webkit-scrollbar-thumb {
      background: #00F0FF;
      border-radius: 3px;
    }
    
    .container {
      max-width: 1280px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 1.5rem;
      padding-right: 1.5rem;
    }
    
    /* 导航栏 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: rgba(10,14,39,0.85);
      backdrop-filter: blur(20px);
      border-bottom: 1px solid rgba(0,240,255,0.2);
      z-index: 50;
      padding: 0.75rem 0;
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      flex-wrap: wrap;
    }
    .logo-text {
      font-weight: 700;
      font-size: 1.5rem;
      background: linear-gradient(135deg, #00F0FF 0%, #5F9EFF 100%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      letter-spacing: 1px;
    }
    .nav-tabs {
      display: flex;
      gap: 8px;
      flex-wrap: wrap;
      align-items: center;
    }
    .nav-chip {
      background: rgba(255,255,255,0.05);
      border-radius: 20px;
      padding: 0.4rem 1rem;
      font-size: 0.9rem;
      color: var(--grey-blue);
      transition: var(--transition-smooth);
      border: 1px solid transparent;
      white-space: nowrap;
    }
    .nav-chip:hover, .nav-chip.active {
      background: var(--cyan);
      color: var(--deep-blue);
      border-color: var(--cyan);
      font-weight: 600;
    }
    .btn-cta-nav {
      background: var(--orange-gold);
      color: white;
      border-radius: 20px;
      padding: 0.5rem 1.4rem;
      font-weight: 600;
      font-size: 0.9rem;
      transition: var(--transition-smooth);
      border: none;
      cursor: pointer;
      box-shadow: 0 0 15px rgba(255,107,53,0.3);
    }
    .btn-cta-nav:hover {
      background: #ff8250;
      box-shadow: 0 0 25px rgba(255,107,53,0.6);
      transform: scale(1.02);
    }
    
    /* 汉堡菜单 (移动端) */
    .menu-toggle {
      display: none;
      background: none;
      border: none;
      color: var(--cyan);
      font-size: 1.8rem;
      cursor: pointer;
    }
    
    /* Hero 双栏 */
    .hero-section {
      padding-top: 7rem;
      padding-bottom: 4rem;
      display: flex;
      align-items: center;
      gap: 2.5rem;
      flex-wrap: wrap;
    }
    .hero-left {
      flex: 1 1 50%;
    }
    .hero-right {
      flex: 1 1 50%;
      min-height: 380px;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      border-radius: 24px;
      position: relative;
      overflow: hidden;
      box-shadow: 0 20px 40px rgba(0,240,255,0.2);
      border: 1px solid rgba(0,240,255,0.25);
    }
    .hero-right::after {
      content: "";
      position: absolute;
      inset: 0;
      background: linear-gradient(135deg, rgba(0,240,255,0.15) 0%, transparent 80%);
      backdrop-filter: blur(3px);
      animation: dataFlow 4s infinite alternate;
    }
    @keyframes dataFlow {
      0% { opacity: 0.5; }
      100% { opacity: 0.9; }
    }
    
    h1 {
      font-size: clamp(2.4rem, 5vw, 3rem);
      font-weight: 700;
      line-height: 1.2;
      letter-spacing: -0.5px;
      color: white;
      margin-bottom: 1.2rem;
    }
    .subtitle {
      font-size: 1.1rem;
      color: var(--grey-blue);
      margin-bottom: 2rem;
      max-width: 500px;
    }
    
    /* 按钮系统 */
    .btn-primary {
      background: var(--cyan);
      color: var(--deep-blue);
      font-weight: 700;
      padding: 0.8rem 2rem;
      border-radius: var(--radius-btn);
      border: none;
      cursor: pointer;
      transition: var(--transition-smooth);
      display: inline-block;
      text-align: center;
      box-shadow: 0 0 15px rgba(0,240,255,0.4);
    }
    .btn-primary:hover {
      box-shadow: 0 0 28px rgba(0,240,255,0.7);
      transform: translateY(-2px);
    }
    .btn-outline {
      background: transparent;
      border: 1px solid var(--cyan);
      color: var(--cyan);
      padding: 0.8rem 2rem;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: var(--transition-smooth);
      display: inline-block;
      text-align: center;
    }
    .btn-outline:hover {
      background: rgba(0,240,255,0.1);
    }
    .btn-cta-large {
      background: var(--orange-gold);
      color: white;
      font-weight: 700;
      padding: 1rem 2.5rem;
      border-radius: 40px;
      font-size: 1.2rem;
      transition: 0.3s;
      border: none;
      cursor: pointer;
      box-shadow: 0 0 25px rgba(255,107,53,0.5);
    }
    .btn-cta-large:hover {
      background: #ff7b4a;
      box-shadow: 0 0 40px #FF6B35;
      transform: scale(1.05);
    }
    
    /* 卡片玻璃拟态 */
    .glass-card {
      background: var(--card-bg);
      backdrop-filter: var(--glass-blur);
      border: 1px solid var(--card-border);
      border-radius: var(--radius-card);
      padding: 1.8rem;
      transition: var(--transition-smooth);
      box-shadow: var(--shadow-cyan);
    }
    .glass-card:hover {
      border-color: var(--cyan);
      box-shadow: 0 12px 36px rgba(0,240,255,0.2);
      transform: translateY(-4px);
    }
    
    .section-title {
      font-size: 2rem;
      font-weight: 700;
      margin-bottom: 2.5rem;
      position: relative;
      display: inline-block;
    }
    .section-title::after {
      content: "";
      position: absolute;
      bottom: -8px;
      left: 0;
      width: 60%;
      height: 4px;
      background: linear-gradient(90deg, var(--cyan), transparent);
      border-radius: 2px;
    }
    
    /* 案例瀑布流 */
    .masonry {
      column-count: 3;
      column-gap: 24px;
    }
    .masonry-item {
      break-inside: avoid;
      margin-bottom: 24px;
      display: block;
    }
    
    /* FAQ 手风琴 */
    .faq-item {
      border-bottom: 1px solid rgba(255,255,255,0.1);
      padding: 1rem 0;
      cursor: pointer;
    }
    .faq-question {
      font-weight: 700;
      font-size: 1.1rem;
      display: flex;
      justify-content: space-between;
      align-items: center;
      color: var(--cold-white);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      color: var(--grey-blue);
      padding-left: 1rem;
      border-left: 3px solid var(--cyan);
      margin-top: 0.5rem;
    }
    .faq-item.open .faq-answer {
      max-height: 200px;
    }
    
    /* 页脚 */
    .footer-links a {
      color: var(--grey-blue);
      transition: color 0.2s;
    }
    .footer-links a:hover {
      color: var(--cyan);
    }
    
    @media (max-width: 1024px) {
      .masonry {
        column-count: 2;
      }
      .hero-section {
        flex-direction: column;
      }
    }
    @media (max-width: 768px) {
      .nav-tabs {
        display: none;
        width: 100%;
        overflow-x: auto;
        flex-wrap: nowrap;
        padding: 0.5rem 0;
        order: 3;
      }
      .nav-tabs.active {
        display: flex;
      }
      .menu-toggle {
        display: block;
      }
      .nav-container {
        flex-wrap: wrap;
      }
      .masonry {
        column-count: 1;
      }
      .hero-right {
        min-height: 280px;
      }
    }