/* roulang page: index */
:root {
      --deep-indigo: #0F1B2D;
      --bronze-gold: #C8A45C;
      --warm-sand: #E8D5B7;
      --dark-gold-green: #2A3A2E;
      --card-bg: rgba(232, 213, 183, 0.06);
      --card-border: rgba(200, 164, 92, 0.2);
      --glass-blur: blur(12px);
      --shadow-gold: 0 4px 24px rgba(200, 164, 92, 0.12);
      --glow-gold: drop-shadow(0 0 8px rgba(200, 164, 92, 0.6));
      --font-serif: 'Noto Serif SC', 'Source Han Serif SC', serif;
      --font-sans: 'Inter', 'PingFang SC', 'Microsoft YaHei', sans-serif;
      --radius-card: 12px;
      --radius-btn: 8px;
      --transition-smooth: all 0.3s ease;
    }
    * {
      box-sizing: border-box;
    }
    body {
      margin: 0;
      font-family: var(--font-sans);
      background-color: var(--deep-indigo);
      color: rgba(232, 213, 183, 0.9);
      line-height: 1.6;
      display: flex;
      min-height: 100vh;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition-smooth);
    }
    button, .btn {
      cursor: pointer;
      font-family: var(--font-sans);
      font-weight: 600;
      border: none;
      background: transparent;
      transition: var(--transition-smooth);
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 0.5rem;
    }
    /* 左侧导航 App Shell */
    .app-nav {
      width: 240px;
      min-width: 240px;
      background-color: var(--deep-indigo);
      border-right: 1px solid rgba(200, 164, 92, 0.25);
      display: flex;
      flex-direction: column;
      padding: 2rem 1.5rem;
      position: fixed;
      top: 0;
      left: 0;
      bottom: 0;
      z-index: 40;
      transition: transform 0.3s ease;
    }
    .nav-logo {
      font-family: var(--font-serif);
      font-size: 1.5rem;
      font-weight: 700;
      color: var(--bronze-gold);
      margin-bottom: 2.5rem;
      letter-spacing: 1px;
      display: flex;
      align-items: center;
      gap: 0.5rem;
    }
    .nav-logo i {
      font-size: 1.8rem;
      color: var(--bronze-gold);
      filter: var(--glow-gold);
    }
    .nav-menu {
      list-style: none;
      padding: 0;
      margin: 0;
      display: flex;
      flex-direction: column;
      gap: 0.25rem;
      flex: 1;
    }
    .nav-item {
      display: block;
    }
    .nav-link {
      display: flex;
      align-items: center;
      gap: 0.75rem;
      padding: 0.8rem 1rem;
      border-radius: 8px;
      color: rgba(232, 213, 183, 0.8);
      font-weight: 500;
      font-size: 0.95rem;
      position: relative;
      transition: var(--transition-smooth);
    }
    .nav-link i {
      width: 20px;
      text-align: center;
      font-size: 1rem;
    }
    .nav-link:hover {
      background: rgba(200, 164, 92, 0.08);
      color: var(--bronze-gold);
    }
    .nav-link.active {
      color: var(--bronze-gold);
      background: rgba(200, 164, 92, 0.12);
      border-left: 3px solid var(--bronze-gold);
      padding-left: calc(1rem - 3px);
    }
    /* 移动端导航触发器 */
    .mobile-nav-toggle {
      display: none;
      position: fixed;
      top: 1rem;
      right: 1rem;
      z-index: 50;
      background: var(--deep-indigo);
      border: 1px solid var(--bronze-gold);
      color: var(--bronze-gold);
      width: 44px;
      height: 44px;
      border-radius: 8px;
      font-size: 1.5rem;
      align-items: center;
      justify-content: center;
    }
    .main-content {
      margin-left: 240px;
      flex: 1;
      width: calc(100% - 240px);
    }
    /* 容器 */
    .container {
      max-width: 1280px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 2rem;
      padding-right: 2rem;
    }
    /* 区块间距 */
    section {
      padding: 5rem 0;
    }
    /* 标题系统 */
    h1, h2, h3 {
      font-family: var(--font-serif);
      font-weight: 600;
    }
    .section-title {
      font-size: 2rem;
      color: var(--warm-sand);
      margin-bottom: 0.75rem;
      font-weight: 600;
    }
    .section-subtitle {
      color: rgba(232, 213, 183, 0.7);
      font-size: 1.1rem;
      margin-bottom: 2.5rem;
    }
    /* 卡片通用 */
    .glass-card {
      background: var(--card-bg);
      backdrop-filter: var(--glass-blur);
      -webkit-backdrop-filter: var(--glass-blur);
      border: 1px solid var(--card-border);
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-gold);
      padding: 2rem;
      transition: var(--transition-smooth);
    }
    .glass-card:hover {
      transform: translateY(-4px);
      box-shadow: 0 8px 32px rgba(200, 164, 92, 0.2);
    }
    /* 按钮 */
    .btn-primary {
      background: var(--bronze-gold);
      color: var(--deep-indigo);
      padding: 0.8rem 2rem;
      border-radius: var(--radius-btn);
      font-weight: 600;
      box-shadow: 0 0 16px rgba(200, 164, 92, 0.3);
    }
    .btn-primary:hover {
      box-shadow: 0 0 24px rgba(200, 164, 92, 0.6);
      background: #d4b06a;
    }
    .btn-secondary {
      background: transparent;
      border: 1px solid var(--bronze-gold);
      color: var(--warm-sand);
      padding: 0.8rem 2rem;
      border-radius: var(--radius-btn);
    }
    .btn-secondary:hover {
      background: rgba(200, 164, 92, 0.1);
    }
    .hero-bg {
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      position: relative;
    }
    .hero-overlay {
      background: linear-gradient(90deg, rgba(15,27,45,0.9) 0%, rgba(15,27,45,0.7) 70%);
      position: absolute;
      inset: 0;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
    }
    .faq-item.active .faq-answer {
      max-height: 150px;
    }
    @media (max-width: 1024px) {
      .app-nav {
        transform: translateX(-100%);
      }
      .app-nav.open {
        transform: translateX(0);
      }
      .main-content {
        margin-left: 0;
        width: 100%;
      }
      .mobile-nav-toggle {
        display: flex;
      }
    }
    @media (max-width: 768px) {
      .container {
        padding-left: 1.5rem;
        padding-right: 1.5rem;
      }
      section {
        padding: 3.5rem 0;
      }
      .btn-primary, .btn-secondary {
        width: 100%;
        justify-content: center;
      }
    }