/* roulang page: index */
:root {
      --primary-deep: #0B0E14;
      --secondary-warm: #F5F0E8;
      --accent-gold: #D9A066;
      --accent-hover: #E0B87A;
      --text-light: #EAE6DF;
      --text-dark: #1C1F26;
      --text-muted: #7B7E85;
      --border-deep: #2A2D35;
      --border-light: #E0DBD2;
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-container: 16px;
      --shadow-card: 0 1px 3px rgba(0,0,0,0.08), 0 6px 16px rgba(0,0,0,0.04);
      --shadow-hover: 0 8px 24px rgba(0,0,0,0.12), 0 2px 6px rgba(0,0,0,0.06);
      --transition-smooth: 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
      --font-sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Inter", system-ui, sans-serif;
    }
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }
    html {
      scroll-behavior: smooth;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--primary-deep);
      color: var(--text-light);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s ease;
    }
    .container {
      max-width: 1280px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 24px;
      padding-right: 24px;
    }
    @media (max-width: 768px) {
      .container {
        padding-left: 16px;
        padding-right: 16px;
      }
    }
    /* 导航样式 */
    .nav-blur {
      background: rgba(11, 14, 20, 0.92);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
    }
    .nav-link {
      position: relative;
      font-size: 14px;
      font-weight: 500;
      color: #EAE6DF;
      transition: color 0.2s;
    }
    .nav-link::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--accent-gold);
      transition: width 0.2s ease;
    }
    .nav-link:hover,
    .nav-link.active {
      color: var(--accent-gold);
    }
    .nav-link.active::after,
    .nav-link:hover::after {
      width: 100%;
    }
    /* 按钮系统 */
    .btn-primary {
      background: var(--accent-gold);
      color: #0B0E14;
      font-weight: 600;
      font-size: 15px;
      letter-spacing: 0.8px;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      border: none;
      cursor: pointer;
      transition: background 0.25s, transform 0.15s;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      min-width: 44px;
      min-height: 44px;
    }
    .btn-primary:hover {
      background: var(--accent-hover);
      transform: translateY(-1px);
    }
    .btn-outline {
      background: transparent;
      border: 1.5px solid var(--accent-gold);
      color: var(--text-light);
      font-weight: 600;
      font-size: 15px;
      letter-spacing: 0.8px;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      transition: background 0.25s, color 0.25s;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      min-width: 44px;
      min-height: 44px;
    }
    .btn-outline:hover {
      background: rgba(217, 160, 102, 0.08);
      color: var(--accent-gold);
    }
    .text-link {
      color: var(--accent-gold);
      font-weight: 500;
      position: relative;
      transition: color 0.2s;
    }
    .text-link::after {
      content: '';
      position: absolute;
      bottom: -2px;
      left: 0;
      width: 0;
      height: 1px;
      background: var(--accent-gold);
      transition: width 0.2s ease;
    }
    .text-link:hover::after {
      width: 100%;
    }
    /* 卡片与容器 */
    .card-light {
      background: var(--secondary-warm);
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
      transition: transform var(--transition-smooth), box-shadow var(--transition-smooth);
      border: 1px solid transparent;
    }
    .card-light:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
      border-color: rgba(217, 160, 102, 0.3);
    }
    .card-deep {
      background: #141820;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
      transition: transform var(--transition-smooth), box-shadow var(--transition-smooth);
    }
    .card-deep:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
      border: 1px solid rgba(217,160,102,0.25);
    }
    /* 动画关键帧 */
    @keyframes fadeUp {
      0% { opacity: 0; transform: translateY(20px); }
      100% { opacity: 1; transform: translateY(0); }
    }
    .animate-fade-up {
      animation: fadeUp 0.5s ease forwards;
    }
    .stagger-item {
      opacity: 0;
    }
    .reveal {
      opacity: 0;
      transform: translateY(20px);
      transition: opacity 0.5s ease, transform 0.5s ease;
    }
    .reveal.visible {
      opacity: 1;
      transform: translateY(0);
    }
    /* FAQ手风琴 */
    .faq-item {
      border-top: 1px solid var(--border-light);
      padding: 20px 0;
      cursor: pointer;
    }
    .faq-question {
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      color: var(--text-dark);
      position: relative;
      padding-left: 16px;
    }
    .faq-question::before {
      content: '';
      position: absolute;
      left: 0;
      top: 2px;
      bottom: 2px;
      width: 3px;
      background: var(--accent-gold);
      opacity: 0;
      transition: opacity 0.2s;
      border-radius: 2px;
    }
    .faq-item.active .faq-question::before {
      opacity: 1;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease;
      color: var(--text-muted);
      padding-left: 16px;
      line-height: 1.7;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-top: 12px;
    }
    .faq-arrow {
      transition: transform 0.3s ease;
      font-size: 18px;
      color: var(--text-muted);
    }
    .faq-item.active .faq-arrow {
      transform: rotate(90deg);
    }
    /* 移动端菜单 */
    .mobile-menu {
      transition: opacity 0.3s ease, visibility 0.3s;
    }
    .hidden-mobile {
      display: none;
    }
    @media (max-width: 768px) {
      .hidden-mobile {
        display: flex;
      }
      .desktop-nav {
        display: none;
      }
    }