/* roulang page: index */
:root {
      --primary-purple: #7B2FF7;
      --primary-cyan: #00F0FF;
      --deep-blue: #0B0C1A;
      --light-bg: #F8F9FF;
      --white: #FFFFFF;
      --accent-orange: #FF6B35;
      --success-green: #00D68F;
      --text-dark: #1A1A2E;
      --text-muted: #5A5A7A;
      --border-light: rgba(0,0,0,0.04);
      --card-radius-lg: 24px;
      --card-radius-md: 16px;
      --btn-radius: 50px;
      --shadow-sm: 0 4px 20px rgba(0,0,0,0.04);
      --shadow-hover: 0 12px 32px rgba(123,47,247,0.15);
      --shadow-glow: 0 8px 40px rgba(0,240,255,0.2);
      --font-sans: 'Inter', 'SF Pro Text', -apple-system, BlinkMacSystemFont, 'PingFang SC', 'Microsoft YaHei', sans-serif;
      --font-mono: 'Inter', 'SF Mono', monospace;
      --transition-base: all 0.25s ease;
    }
    * {
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--white);
      color: var(--text-dark);
      line-height: 1.7;
      margin: 0;
      overflow-x: hidden;
      font-size: 16px;
    }
    h1, h2, h3, h4, .navbar-brand, .btn, .nav-link {
      font-family: var(--font-sans);
      letter-spacing: -0.02em;
    }
    /* 导航 */
    .navbar {
      transition: var(--transition-base);
      padding: 1rem 0;
      background: transparent;
      z-index: 1020;
    }
    .navbar.scrolled {
      background: rgba(255,255,255,0.88);
      backdrop-filter: blur(20px);
      box-shadow: 0 4px 20px rgba(0,0,0,0.04);
    }
    .navbar .navbar-brand {
      font-weight: 700;
      font-size: 1.8rem;
      background: linear-gradient(135deg, var(--primary-purple), var(--primary-cyan));
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      display: flex;
      align-items: center;
      gap: 0.5rem;
    }
    .brand-icon {
      font-size: 2rem;
      background: linear-gradient(135deg, var(--primary-purple), var(--primary-cyan));
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }
    .navbar .nav-link {
      color: var(--text-dark);
      font-weight: 500;
      margin: 0 0.75rem;
      position: relative;
      padding: 0.5rem 0;
      transition: var(--transition-base);
      font-size: 1rem;
    }
    .navbar.scrolled .nav-link {
      color: var(--text-dark);
    }
    .hero-active .nav-link {
      color: white;
    }
    .nav-link::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: linear-gradient(135deg, var(--primary-purple), var(--primary-cyan));
      transition: width 0.2s ease;
    }
    .nav-link:hover::after,
    .nav-link.active::after {
      width: 100%;
    }
    .navbar-toggler {
      border: none;
      color: var(--text-dark);
    }
    .navbar-toggler:focus {
      box-shadow: none;
    }
    .mobile-menu {
      background: var(--deep-blue);
      backdrop-filter: blur(30px);
    }
    .mobile-menu .nav-link {
      color: white;
      font-size: 1.5rem;
      margin: 1rem 0;
    }
    @media (max-width: 991px) {
      .navbar-collapse {
        background: rgba(11,12,26,0.95);
        backdrop-filter: blur(20px);
        padding: 2rem;
        border-radius: 24px;
        margin-top: 1rem;
      }
      .navbar-collapse .nav-link {
        color: white;
      }
    }
    /* Hero */
    #hero {
      min-height: 100vh;
      background: linear-gradient(135deg, #7B2FF7 0%, #00F0FF 100%);
      position: relative;
      display: flex;
      align-items: center;
      overflow: hidden;
    }
    .hero-overlay {
      position: absolute;
      inset: 0;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      opacity: 0.15;
      mix-blend-mode: overlay;
    }
    .hero-content {
      position: relative;
      z-index: 2;
      text-align: center;
      color: white;
      padding: 2rem 0;
    }
    .hero-title {
      font-size: 3.8rem;
      font-weight: 700;
      background: linear-gradient(to right, #ffffff, #e0e0ff);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      margin-bottom: 1.5rem;
    }
    .hero-sub {
      font-size: 1.2rem;
      color: rgba(255,255,255,0.9);
      max-width: 650px;
      margin: 0 auto 2rem;
    }
    .btn-primary-grad {
      background: linear-gradient(135deg, var(--primary-purple), var(--primary-cyan));
      border: none;
      color: white;
      padding: 0.9rem 2.5rem;
      border-radius: var(--btn-radius);
      font-weight: 600;
      transition: var(--transition-base);
      box-shadow: 0 8px 20px rgba(123,47,247,0.3);
    }
    .btn-primary-grad:hover {
      background: linear-gradient(135deg, var(--primary-cyan), var(--primary-purple));
      box-shadow: 0 12px 28px rgba(123,47,247,0.5);
      transform: scale(1.02);
      color: white;
    }
    .btn-outline-light-custom {
      border: 2px solid white;
      background: transparent;
      color: white;
      padding: 0.85rem 2.3rem;
      border-radius: var(--btn-radius);
      font-weight: 600;
      transition: var(--transition-base);
    }
    .btn-outline-light-custom:hover {
      background: rgba(255,255,255,0.15);
      color: white;
    }
    .float-badge {
      background: rgba(255,255,255,0.12);
      backdrop-filter: blur(12px);
      border-radius: 50px;
      padding: 0.5rem 1.8rem;
      color: white;
      font-weight: 500;
      display: inline-flex;
      align-items: center;
      gap: 0.5rem;
      font-size: 0.95rem;
    }
    /* 区块通用 */
    section {
      padding: 5rem 0;
    }
    .section-title {
      font-size: 2.3rem;
      font-weight: 700;
      margin-bottom: 0.75rem;
    }
    .section-sub {
      color: var(--text-muted);
      font-size: 1.1rem;
      margin-bottom: 3rem;
    }
    .gradient-line {
      width: 60px;
      height: 4px;
      background: linear-gradient(135deg, var(--primary-purple), var(--primary-cyan));
      border-radius: 4px;
      margin: 0.8rem 0 1.5rem;
    }
    /* 卡片 */
    .feature-card {
      background: var(--white);
      border-radius: var(--card-radius-lg);
      padding: 2rem;
      border: 1px solid var(--border-light);
      transition: var(--transition-base);
      box-shadow: var(--shadow-sm);
      height: 100%;
    }
    .feature-card:hover {
      transform: translateY(-8px);
      box-shadow: var(--shadow-hover);
      border-color: rgba(123,47,247,0.2);
    }
    .icon-gradient {
      font-size: 2.2rem;
      background: linear-gradient(135deg, var(--primary-purple), var(--primary-cyan));
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }
    .tech-badge {
      background: rgba(123,47,247,0.08);
      color: var(--primary-purple);
      border-radius: 20px;
      padding: 0.25rem 1rem;
      font-size: 0.8rem;
      font-weight: 600;
    }
    .img-cover {
      width: 100%;
      height: auto;
      border-radius: 20px;
      object-fit: cover;
    }
    .scene-card {
      border-radius: var(--card-radius-lg);
      overflow: hidden;
      position: relative;
      background: #111;
    }
    .scene-card img {
      transition: transform 0.4s ease;
      width: 100%;
      height: 260px;
      object-fit: cover;
      display: block;
    }
    .scene-card:hover img {
      transform: scale(1.05);
    }
    .scene-overlay {
      position: absolute;
      bottom: 0;
      left: 0;
      right: 0;
      background: linear-gradient(transparent, rgba(0,0,0,0.75));
      color: white;
      padding: 2rem 1.5rem 1.5rem;
    }
    .pricing-card {
      background: white;
      border-radius: var(--card-radius-lg);
      padding: 2.5rem 2rem;
      box-shadow: var(--shadow-sm);
      transition: var(--transition-base);
      border: 1px solid var(--border-light);
    }
    .pricing-card.featured {
      background: linear-gradient(135deg, var(--primary-purple), var(--primary-cyan));
      color: white;
      transform: scale(1.03);
      box-shadow: var(--shadow-glow);
      border: none;
    }
    .price-number {
      font-size: 3rem;
      font-weight: 700;
      font-family: var(--font-mono);
    }
    .accordion-button {
      font-weight: 600;
      font-size: 1.1rem;
      background: transparent;
      box-shadow: none;
      border-bottom: 1px solid #eee;
      padding: 1.2rem 0;
    }
    .accordion-button:not(.collapsed) {
      background: transparent;
      color: var(--primary-purple);
    }
    .accordion-body {
      color: var(--text-muted);
      padding-left: 1.8rem;
    }
    footer {
      background: var(--deep-blue);
      color: rgba(255,255,255,0.7);
    }
    .footer-link {
      color: rgba(255,255,255,0.65);
      text-decoration: none;
      transition: 0.2s;
    }
    .footer-link:hover {
      color: white;
      padding-left: 4px;
    }
    .social-icon {
      font-size: 1.4rem;
      color: white;
      margin-right: 1rem;
      transition: 0.2s;
    }
    .social-icon:hover {
      color: var(--primary-cyan);
    }
    @media (max-width: 768px) {
      .hero-title { font-size: 2.5rem; }
      section { padding: 3rem 0; }
    }