/* roulang page: index */
:root {
      --bg-deep: #0A0E27;
      --accent-cyan: #00F0B4;
      --electric-purple: #7B2FFF;
      --glass-bg: rgba(255, 255, 255, 0.03);
      --glass-border: rgba(255, 255, 255, 0.08);
      --text-white: #FFFFFF;
      --text-body: #B0B8D0;
      --text-muted: #5A6080;
      --glow-cyan: 0 0 20px rgba(0, 240, 180, 0.4);
      --glow-purple: 0 0 20px rgba(123, 47, 255, 0.4);
      --border-radius-card: 16px;
      --border-radius-btn: 8px;
      --border-radius-pill: 50px;
      --shadow-card: 0 8px 32px rgba(0,0,0,0.4);
      --shadow-hover: 0 12px 40px rgba(0,0,0,0.5), 0 0 30px rgba(0,240,180,0.1);
      --font-sans: 'PingFang SC', 'Microsoft YaHei', 'Hiragino Sans GB', sans-serif;
      --font-numbers: 'Inter', sans-serif;
    }
    * {
      box-sizing: border-box;
    }
    body {
      background-color: var(--bg-deep);
      color: var(--text-body);
      font-family: var(--font-sans);
      line-height: 1.7;
      margin: 0;
      overflow-x: hidden;
    }
    h1, h2, h3, h4 {
      font-family: var(--font-sans);
      color: var(--text-white);
      letter-spacing: -0.01em;
    }
    .font-numbers {
      font-family: var(--font-numbers);
      font-weight: 700;
    }
    a {
      color: var(--text-body);
      transition: color 0.2s, border-color 0.2s;
      text-decoration: none;
    }
    a:hover {
      color: var(--accent-cyan);
    }
    .container-custom {
      max-width: 1200px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 1.5rem;
      padding-right: 1.5rem;
    }
    @media (max-width: 768px) {
      .container-custom {
        padding-left: 1rem;
        padding-right: 1rem;
      }
    }
    /* 导航 */
    #nav {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      transition: background 0.3s, backdrop-filter 0.3s, box-shadow 0.3s;
      background: transparent;
      border-bottom: 1px solid transparent;
    }
    #nav.scrolled {
      background: rgba(10, 14, 39, 0.9);
      backdrop-filter: blur(20px);
      border-bottom: 1px solid rgba(255,255,255,0.06);
      box-shadow: 0 2px 20px rgba(0,0,0,0.6);
    }
    .nav-brand {
      font-family: var(--font-numbers);
      font-weight: 800;
      font-size: 1.4rem;
      color: var(--text-white);
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .nav-brand i {
      color: var(--accent-cyan);
      font-size: 1.8rem;
      text-shadow: 0 0 10px rgba(0,240,180,0.6);
    }
    .nav-link-custom {
      color: var(--text-body) !important;
      font-weight: 500;
      font-size: 0.9rem;
      padding: 0.5rem 0.75rem !important;
      position: relative;
      transition: 0.2s;
    }
    .nav-link-custom:hover, .nav-link-custom.active {
      color: var(--accent-cyan) !important;
    }
    .nav-link-custom::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0.75rem;
      right: 0.75rem;
      height: 2px;
      background: var(--accent-cyan);
      box-shadow: 0 0 12px var(--accent-cyan);
      transform: scaleX(0);
      transition: transform 0.2s;
    }
    .nav-link-custom:hover::after, .nav-link-custom.active::after {
      transform: scaleX(1);
    }
    .hot-tag {
      background: rgba(0,240,180,0.1);
      border: 1px solid rgba(0,240,180,0.25);
      color: var(--accent-cyan);
      border-radius: 50px;
      padding: 0.2rem 0.75rem;
      font-size: 0.75rem;
      font-weight: 500;
    }
    .search-icon {
      color: var(--text-body);
      font-size: 1.2rem;
      cursor: pointer;
      transition: 0.2s;
    }
    .search-icon:hover {
      color: var(--accent-cyan);
      text-shadow: 0 0 12px var(--accent-cyan);
    }
    .navbar-toggler {
      border: 1px solid rgba(255,255,255,0.2);
      color: var(--accent-cyan);
    }
    .navbar-toggler:focus {
      box-shadow: 0 0 10px rgba(0,240,180,0.3);
    }
    @media (max-width: 992px) {
      .navbar-collapse {
        background: rgba(10,14,39,0.95);
        backdrop-filter: blur(20px);
        padding: 1rem;
        border-radius: 12px;
        margin-top: 0.5rem;
      }
    }
    /* 区块间距 */
    section {
      padding: 5rem 0;
    }
    @media (max-width: 768px) {
      section {
        padding: 3rem 0;
      }
    }
    /* 标题装饰线 */
    .section-title {
      font-size: 2.4rem;
      font-weight: 700;
      margin-bottom: 1rem;
      position: relative;
      display: inline-block;
      color: var(--text-white);
    }
    .section-title::before {
      content: '';
      position: absolute;
      left: 0;
      bottom: -8px;
      width: 40px;
      height: 3px;
      background: var(--accent-cyan);
      border-radius: 3px;
      box-shadow: 0 0 15px var(--accent-cyan);
    }
    @media (max-width: 768px) {
      .section-title {
        font-size: 1.8rem;
      }
    }
    /* 玻璃卡片 */
    .glass-card {
      background: var(--glass-bg);
      backdrop-filter: blur(20px);
      border: 1px solid var(--glass-border);
      border-radius: var(--border-radius-card);
      box-shadow: var(--shadow-card);
      transition: all 0.3s ease;
    }
    .glass-card:hover {
      border-color: rgba(0,240,180,0.3);
      box-shadow: var(--shadow-hover);
      transform: translateY(-4px);
    }
    /* 按钮 */
    .btn-primary-glow {
      background: linear-gradient(135deg, #00F0B4, #00C9A0);
      border: none;
      color: #0A0E27;
      font-weight: 700;
      border-radius: var(--border-radius-btn);
      padding: 0.75rem 2rem;
      box-shadow: 0 0 20px rgba(0,240,180,0.4);
      transition: 0.25s;
    }
    .btn-primary-glow:hover {
      box-shadow: 0 0 35px rgba(0,240,180,0.6);
      transform: scale(1.03);
      color: #0A0E27;
    }
    .btn-outline-light-glow {
      background: transparent;
      border: 1.5px solid rgba(255,255,255,0.25);
      color: white;
      border-radius: var(--border-radius-btn);
      padding: 0.75rem 2rem;
      font-weight: 600;
      transition: 0.25s;
    }
    .btn-outline-light-glow:hover {
      border-color: var(--accent-cyan);
      color: var(--accent-cyan);
      box-shadow: 0 0 15px rgba(0,240,180,0.2);
    }
    /* Hero */
    #hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      padding-top: 80px;
      background: radial-gradient(circle at 30% 40%, rgba(0,240,180,0.08) 0%, transparent 45%);
    }
    .hero-title {
      font-size: 3.5rem;
      font-weight: 800;
      line-height: 1.15;
    }
    @media (max-width: 768px) {
      .hero-title {
        font-size: 2.2rem;
      }
    }
    /* 数据指标 */
    .metric-number {
      font-family: var(--font-numbers);
      font-size: 2.2rem;
      font-weight: 700;
      color: var(--accent-cyan);
      text-shadow: 0 0 18px rgba(0,240,180,0.5);
    }
    /* FAQ */
    .accordion-button {
      background: rgba(255,255,255,0.02);
      border: 1px solid rgba(255,255,255,0.05);
      border-radius: 12px !important;
      color: var(--text-white);
      font-weight: 600;
      box-shadow: none;
    }
    .accordion-button:not(.collapsed) {
      background: rgba(0,240,180,0.05);
      color: var(--accent-cyan);
      box-shadow: none;
    }
    .accordion-button::after {
      filter: brightness(0) invert(1);
    }
    .accordion-item {
      background: transparent;
      border: none;
      margin-bottom: 0.75rem;
    }
    .footer-link {
      color: var(--text-body);
    }
    .footer-link:hover {
      color: var(--accent-cyan);
    }

@keyframes pulse { 0% { opacity: 0.6; transform: translateY(0); } 50% { opacity: 1; transform: translateY(5px); } 100% { opacity: 0.6; transform: translateY(0); } }
    .bg-accent-cyan { background-color: #00F0B4; }
    .text-cyan { color: #00F0B4; }
    .border-cyan { border-color: rgba(0,240,180,0.5); }
    .border-purple { border-color: rgba(123,47,255,0.5); }
    .text-purple { color: #7B2FFF; }
    .grayscale { filter: grayscale(1); transition: 0.3s; }
    .grayscale:hover { filter: grayscale(0); }
    .form-control:focus {
      border-color: #00F0B4;
      box-shadow: 0 0 10px rgba(0,240,180,0.3);
    }