/* roulang page: index */
:root {
      --primary-start: #4A00E0;
      --primary-end: #00E5FF;
      --accent: #F5A623;
      --bg-page: #F8F9FC;
      --white: #FFFFFF;
      --dark-bg: #0B0C10;
      --text-dark: #1A1A2E;
      --text-body: #4A4A6A;
      --text-muted: #6B6B80;
      --border-light: #E8ECF1;
      --card-shadow: 0 4px 20px rgba(0,0,0,0.04);
      --card-shadow-hover: 0 12px 32px rgba(0,0,0,0.08);
      --radius-lg: 16px;
      --radius-xl: 20px;
      --radius-full: 50px;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", sans-serif;
      --font-mono: "Inter", "SF Pro Display", sans-serif;
    }
    * {
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--bg-page);
      color: var(--text-body);
      line-height: 1.75;
      margin: 0;
      padding: 0;
      -webkit-font-smoothing: antialiased;
    }
    h1, h2, h3, h4 {
      font-family: var(--font-sans);
      color: var(--text-dark);
      margin-top: 0;
    }
    .gradient-text {
      background: linear-gradient(135deg, var(--primary-start), var(--primary-end));
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }
    .gradient-bg {
      background: linear-gradient(135deg, var(--primary-start), var(--primary-end));
    }
    .glass-nav {
      background: rgba(255,255,255,0.7);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      border-bottom: 1px solid rgba(255,255,255,0.2);
      box-shadow: 0 4px 30px rgba(0,0,0,0.03);
    }
    .glass-nav.scrolled {
      background: rgba(255,255,255,0.95);
      box-shadow: 0 10px 25px -5px rgba(0,0,0,0.05);
    }
    .btn-primary {
      background: linear-gradient(135deg, var(--primary-start), var(--primary-end));
      border-radius: var(--radius-full);
      padding: 12px 28px;
      color: white;
      font-weight: 600;
      transition: all 0.3s ease;
      box-shadow: 0 4px 15px rgba(0,229,255,0.25);
      display: inline-block;
      text-align: center;
      border: none;
      cursor: pointer;
    }
    .btn-primary:hover {
      box-shadow: 0 0 20px rgba(0,229,255,0.5);
      transform: translateY(-1px);
    }
    .btn-outline {
      background: transparent;
      border: 1.5px solid var(--primary-start);
      color: var(--primary-start);
      border-radius: var(--radius-full);
      padding: 12px 28px;
      font-weight: 600;
      transition: all 0.3s ease;
      display: inline-block;
      text-align: center;
    }
    .btn-outline:hover {
      background: rgba(74,0,224,0.05);
      border-color: var(--primary-end);
      color: var(--primary-end);
    }
    .card-hover {
      transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1.2);
      border-radius: var(--radius-lg);
      background: var(--white);
      box-shadow: var(--card-shadow);
    }
    .card-hover:hover {
      box-shadow: var(--card-shadow-hover);
      transform: translateY(-4px);
    }
    .badge-accent {
      background-color: rgba(245,166,35,0.12);
      color: var(--accent);
      font-weight: 600;
      font-size: 0.85rem;
      border-radius: 30px;
      padding: 4px 12px;
      display: inline-block;
    }
    .faq-item {
      border: 1px solid var(--border-light);
      border-radius: 12px;
      background: var(--white);
      transition: background 0.3s;
    }
    .faq-item.active {
      background: #F4F6FC;
    }
    input:focus, textarea:focus {
      outline: none;
      border-color: var(--primary-start);
      box-shadow: 0 0 0 3px rgba(0,229,255,0.15);
    }
    .masonry-grid {
      column-count: 3;
      column-gap: 24px;
    }
    @media (max-width: 1024px) {
      .masonry-grid {
        column-count: 2;
      }
    }
    @media (max-width: 640px) {
      .masonry-grid {
        column-count: 1;
      }
    }
    .masonry-item {
      break-inside: avoid;
      margin-bottom: 24px;
    }
    @media (max-width: 768px) {
      .hero-visual {
        margin-top: 2rem;
        height: 280px;
      }
    }