/* roulang page: index */
:root {
      --brand-gradient-start: #FF4D2E;
      --brand-gradient-end: #FF7A45;
      --brand-gradient: linear-gradient(135deg, #FF4D2E 0%, #FF7A45 100%);
      --brand-dark: #0F1923;
      --brand-gold: #F5A623;
      --bg-light: #FAFAFC;
      --bg-card: #ffffff;
      --bg-warm: #F7F5F4;
      --text-primary: #1E1E24;
      --text-secondary: #555;
      --text-muted: #767676;
      --border-light: #e9e9ef;
      --shadow-sm: 0 4px 20px rgba(0,0,0,0.04);
      --shadow-hover: 0 12px 32px rgba(0,0,0,0.08);
      --radius-lg: 24px;
      --radius-md: 16px;
      --radius-sm: 12px;
      --radius-btn: 50px;
      --transition: 0.25s ease;
    }
    * {
      box-sizing: border-box;
    }
    body {
      font-family: system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', 'Noto Sans', 'PingFang SC', 'Microsoft YaHei', sans-serif;
      background-color: var(--bg-light);
      color: var(--text-primary);
      line-height: 1.7;
      margin: 0;
      padding-top: 90px;
      scroll-behavior: smooth;
    }
    h1, h2, h3, h4, .h1, .h2, .h3, .h4 {
      font-weight: 700;
      letter-spacing: -0.02em;
    }
    h1 {
      font-size: 3.2rem;
      line-height: 1.2;
    }
    h2 {
      font-size: 2.4rem;
    }
    h3 {
      font-size: 1.6rem;
    }
    .lead {
      font-size: 1.15rem;
      font-weight: 400;
      color: var(--text-secondary);
      max-width: 68ch;
    }
    .container {
      max-width: 1200px;
      padding-left: 20px;
      padding-right: 20px;
    }
    /* 浮动 Dock 导航 */
    .navbar-dock {
      position: fixed;
      top: 20px;
      left: 50%;
      transform: translateX(-50%);
      width: auto;
      max-width: 720px;
      background: rgba(255, 255, 255, 0.88);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      border-radius: 40px;
      padding: 8px 24px;
      box-shadow: 0 8px 24px rgba(0,0,0,0.06);
      z-index: 1000;
      display: flex;
      align-items: center;
      justify-content: space-between;
      border: 1px solid rgba(255,255,255,0.5);
    }
    .navbar-dock .logo {
      font-weight: 800;
      font-size: 1.4rem;
      background: var(--brand-gradient);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      white-space: nowrap;
      margin-right: 24px;
    }
    .nav-links {
      display: flex;
      gap: 20px;
      align-items: center;
    }
    .nav-links a {
      text-decoration: none;
      color: var(--text-primary);
      font-weight: 500;
      font-size: 0.95rem;
      transition: color 0.2s;
      white-space: nowrap;
    }
    .nav-links a:hover {
      color: var(--brand-gradient-start);
    }
    .btn-nav-cta {
      background: var(--brand-gradient);
      border: none;
      color: white;
      padding: 8px 20px;
      border-radius: 40px;
      font-weight: 600;
      font-size: 0.9rem;
      transition: 0.2s;
      white-space: nowrap;
      margin-left: 20px;
      box-shadow: 0 4px 10px rgba(255,77,46,0.3);
    }
    .btn-nav-cta:hover {
      filter: brightness(1.1);
      color: white;
      transform: translateY(-1px);
    }
    /* 移动端底部Dock */
    @media (max-width: 768px) {
      body {
        padding-top: 20px;
      }
      .navbar-dock {
        top: auto;
        bottom: 12px;
        left: 10px;
        right: 10px;
        transform: none;
        width: auto;
        max-width: 100%;
        border-radius: 28px;
        padding: 10px 18px;
        background: rgba(30,30,36,0.92);
        backdrop-filter: blur(20px);
        border: 1px solid rgba(255,255,255,0.15);
        justify-content: space-around;
      }
      .navbar-dock .logo {
        font-size: 1rem;
        margin-right: 0;
        -webkit-text-fill-color: white;
        background: none;
        color: white;
      }
      .nav-links a {
        color: rgba(255,255,255,0.85);
        font-size: 0.75rem;
        gap: 12px;
      }
      .btn-nav-cta {
        margin-left: 6px;
        padding: 6px 14px;
        font-size: 0.75rem;
        background: var(--brand-gradient);
      }
      h1 {
        font-size: 2.2rem;
      }
      h2 {
        font-size: 1.9rem;
      }
      .navbar-dock .nav-links {
        gap: 12px;
      }
    }
    /* 板块间距 */
    section {
      padding: 90px 0;
    }
    @media (max-width: 768px) {
      section {
        padding: 60px 0;
      }
    }
    /* 卡片基础 */
    .card-custom {
      background: var(--bg-card);
      border-radius: var(--radius-lg);
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      border: none;
      height: 100%;
    }
    .card-custom:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
    }
    .badge-gold {
      background: var(--brand-gold);
      color: #0F1923;
      font-weight: 700;
      padding: 4px 12px;
      border-radius: 30px;
      font-size: 0.8rem;
      letter-spacing: 0.3px;
    }
    .data-badge {
      font-size: 2.5rem;
      font-weight: 800;
      background: var(--brand-gradient);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      line-height: 1;
    }
    .btn-primary-gradient {
      background: var(--brand-gradient);
      border: none;
      color: white;
      font-weight: 600;
      padding: 12px 32px;
      border-radius: var(--radius-btn);
      transition: 0.25s;
      box-shadow: 0 8px 18px rgba(255,77,46,0.25);
    }
    .btn-primary-gradient:hover {
      filter: brightness(1.08);
      transform: translateY(-2px);
      box-shadow: 0 12px 24px rgba(255,77,46,0.35);
      color: white;
    }
    .btn-outline-light-custom {
      border: 2px solid white;
      color: white;
      border-radius: 50px;
      padding: 10px 28px;
      font-weight: 600;
      background: transparent;
      transition: 0.2s;
    }
    .btn-outline-light-custom:hover {
      background: rgba(255,255,255,0.15);
      color: white;
      border-color: white;
    }
    .img-rounded {
      border-radius: 24px;
      object-fit: cover;
      width: 100%;
      height: auto;
      box-shadow: 0 8px 24px rgba(0,0,0,0.06);
    }
    footer {
      background: #1A1A20;
      color: #ccc;
      padding: 50px 0 20px;
    }
    footer a {
      color: #ccc;
      text-decoration: none;
    }
    footer a:hover {
      color: var(--brand-gradient-start);
    }
    .faq-question {
      cursor: pointer;
      font-weight: 600;
      background: white;
      border: none;
      width: 100%;
      text-align: left;
      padding: 20px 24px;
      border-radius: var(--radius-md);
      box-shadow: 0 2px 12px rgba(0,0,0,0.02);
      transition: 0.2s;
    }
    .faq-answer {
      background: #F9F9FB;
      border-radius: 0 0 var(--radius-md) var(--radius-md);
      padding: 0 24px;
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease, padding 0.35s ease;
    }
    .faq-item.active .faq-answer {
      padding: 20px 24px;
      max-height: 300px;
    }
    .faq-item.active .faq-question {
      color: var(--brand-gradient-start);
    }