/* roulang page: index */
/* ===== 设计变量与基础重置 ===== */
    :root {
      --primary-deep: #1E2D2B;
      --accent-gold: #C89B5E;
      --accent-gold-hover: #B0874A;
      --bg-warm: #FAF9F6;
      --bg-muted: #EEF2F0;
      --dark-section: #15231F;
      --text-primary: #1A1A1A;
      --text-body: #3A3A3A;
      --text-muted: #6B6B6B;
      --text-on-dark: #F5F3EE;
      --border-soft: #E0E0E0;
      --card-shadow: 0 4px 20px rgba(0,0,0,0.04);
      --card-shadow-hover: 0 8px 30px rgba(0,0,0,0.08);
      --radius-card: 12px;
      --radius-sm: 8px;
      --transition-smooth: 0.3s ease;
    }
    
    * {
      box-sizing: border-box;
    }
    
    html {
      scroll-behavior: smooth;
    }
    
    body {
      margin: 0;
      font-family: 'Inter', 'PingFang SC', '苹方', system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
      background-color: var(--bg-warm);
      color: var(--text-body);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }
    
    /* 标题使用衬线体 */
    h1, h2, h3, .serif-title, .logo-text {
      font-family: 'Noto Serif SC', '思源宋体 CN', 'Times New Roman', serif;
      font-weight: 700;
      letter-spacing: -0.01em;
    }
    
    .container {
      max-width: 1280px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 1.5rem;
      padding-right: 1.5rem;
    }
    
    /* 链接与图片基础 */
    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s;
    }
    img {
      max-width: 100%;
      display: block;
      height: auto;
    }
    button, input, textarea {
      font-family: inherit;
    }
    
    /* 金色分割线 */
    .gold-divider {
      width: 200px;
      height: 1px;
      background: rgba(200, 155, 94, 0.2);
      margin: 0 auto;
    }
    
    /* 导航固定与阴影 */
    header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: rgba(250, 249, 246, 0.92);
      backdrop-filter: blur(12px);
      z-index: 50;
      height: 72px;
      display: flex;
      align-items: center;
      transition: box-shadow 0.3s ease;
      border-bottom: 1px solid transparent;
    }
    header.scrolled {
      box-shadow: 0 4px 20px rgba(0,0,0,0.04);
      border-bottom-color: rgba(200,155,94,0.12);
    }
    
    .nav-link {
      position: relative;
      padding: 0.5rem 0;
      font-weight: 500;
      color: var(--text-primary);
      transition: color 0.2s;
    }
    .nav-link::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0%;
      height: 2px;
      background: var(--accent-gold);
      transition: width 0.3s ease;
    }
    .nav-link:hover, .nav-link.active {
      color: var(--primary-deep);
    }
    .nav-link:hover::after, .nav-link.active::after {
      width: 100%;
    }
    
    /* 按钮系统 */
    .btn-primary {
      background: var(--accent-gold);
      color: #1E2D2B;
      font-weight: 600;
      border-radius: var(--radius-sm);
      padding: 0.75rem 2rem;
      display: inline-block;
      transition: background 0.2s, transform 0.2s;
      border: none;
      cursor: pointer;
      box-shadow: 0 2px 8px rgba(200,155,94,0.15);
    }
    .btn-primary:hover {
      background: var(--accent-gold-hover);
      transform: translateY(-1px);
    }
    .btn-outline {
      background: transparent;
      border: 1.5px solid var(--accent-gold);
      color: var(--accent-gold);
      font-weight: 600;
      border-radius: var(--radius-sm);
      padding: 0.75rem 2rem;
      display: inline-block;
      transition: all 0.25s;
      cursor: pointer;
    }
    .btn-outline:hover {
      background: rgba(200,155,94,0.08);
      border-color: var(--accent-gold-hover);
      color: #b08a4a;
      transform: translateY(-1px);
    }
    
    /* 卡片样式 */
    .card {
      background: #fff;
      border-radius: var(--radius-card);
      box-shadow: var(--card-shadow);
      transition: box-shadow 0.3s, transform 0.3s;
    }
    .card:hover {
      box-shadow: var(--card-shadow-hover);
      transform: translateY(-2px);
    }
    
    /* 手风琴动画 */
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease, padding 0.3s;
    }
    .faq-item.open .faq-answer {
      max-height: 300px;
      padding: 0 1.5rem 1.5rem 1.5rem;
    }
    
    /* 背景纹理噪点（极淡） */
    .texture-bg {
      position: relative;
    }
    .texture-bg::before {
      content: "";
      position: absolute;
      top: 0; left: 0; width: 100%; height: 100%;
      background-image: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" width="100" height="100"><filter id="noise"><feTurbulence type="fractalNoise" baseFrequency="0.8" stitchTiles="stitch"/></filter><rect width="100" height="100" filter="url(/%23noise)" opacity="0.03"/></svg>');
      pointer-events: none;
      z-index: 0;
    }
    
    @media (max-width: 768px) {
      header { height: 64px; }
      .container { padding-left: 1.25rem; padding-right: 1.25rem; }
    }