/* roulang page: index */
:root {
      --primary: #1A1A2E;
      --accent: #E94560;
      --bg: #F8F9FA;
      --card: #FFFFFF;
      --text: #212529;
      --text-secondary: #6C757D;
      --border: #DEE2E6;
      --shadow-sm: 0 1px 3px rgba(0,0,0,0.06), 0 1px 2px rgba(0,0,0,0.04);
      --shadow-hover: 0 10px 25px rgba(0,0,0,0.1);
      --radius-card: 12px;
      --radius-btn: 8px;
      --transition: 0.3s ease;
    }
    * {
      box-sizing: border-box;
    }
    body {
      font-family: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Noto Sans SC", -apple-system, sans-serif;
      color: var(--text);
      background-color: var(--bg);
      line-height: 1.7;
      margin: 0;
      -webkit-font-smoothing: antialiased;
    }
    h1, h2, h3, h4 {
      font-weight: 600;
      line-height: 1.3;
      color: var(--primary);
    }
    h1 {
      font-size: clamp(2.2rem, 5vw, 3rem);
      font-weight: 700;
      line-height: 1.2;
    }
    h2 {
      font-size: clamp(1.8rem, 4vw, 2.2rem);
      margin-bottom: 1rem;
    }
    h3 {
      font-size: 1.35rem;
      font-weight: 600;
    }
    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }
    @media (max-width: 640px) {
      .container {
        padding: 0 16px;
      }
    }
    /* 导航样式 */
    .main-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 50;
      background-color: rgba(255,255,255,0.92);
      backdrop-filter: blur(12px);
      box-shadow: 0 1px 4px rgba(0,0,0,0.04);
      transition: all 0.3s ease;
    }
    .nav-brand {
      font-weight: 700;
      font-size: 1.6rem;
      letter-spacing: -0.5px;
      color: var(--primary);
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .nav-brand i {
      color: var(--accent);
      font-size: 1.8rem;
    }
    .nav-link {
      font-weight: 500;
      color: var(--text);
      transition: color 0.2s;
      padding: 0.4rem 0.8rem;
      border-radius: 6px;
    }
    .nav-link:hover {
      color: var(--accent);
      background-color: rgba(233,69,96,0.05);
    }
    .trend-tag {
      background: #f1f1f1;
      color: var(--primary);
      font-size: 0.8rem;
      font-weight: 500;
      padding: 0.2rem 0.8rem;
      border-radius: 20px;
      transition: all 0.2s;
    }
    .trend-tag:hover {
      background: var(--accent);
      color: white;
    }
    .mobile-menu {
      display: none;
    }
    @media (max-width: 1023px) {
      .desktop-nav-links {
        display: none;
      }
      .mobile-menu {
        display: block;
      }
    }
    /* Hero */
    .hero-section {
      min-height: 85vh;
      display: flex;
      align-items: center;
      background: linear-gradient(135deg, #f8f9fa 0%, #ffffff 100%);
      margin-top: 80px;
    }
    .btn-primary {
      background: var(--accent);
      color: white;
      font-weight: 600;
      padding: 12px 32px;
      border-radius: var(--radius-btn);
      box-shadow: 0 4px 12px rgba(233,69,96,0.3);
      transition: all 0.2s ease;
      display: inline-block;
      text-align: center;
      letter-spacing: 0.5px;
    }
    .btn-primary:hover {
      background: #C23152;
      transform: scale(1.03);
      box-shadow: 0 8px 20px rgba(233,69,96,0.4);
    }
    .btn-outline {
      border: 2px solid var(--primary);
      color: var(--primary);
      font-weight: 600;
      padding: 10px 30px;
      border-radius: var(--radius-btn);
      transition: all 0.2s ease;
      display: inline-block;
      text-align: center;
    }
    .btn-outline:hover {
      background: var(--primary);
      color: white;
    }
    /* 卡片 */
    .highlight-card {
      background: var(--card);
      border-radius: var(--radius-card);
      padding: 28px 20px;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      text-align: center;
    }
    .highlight-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
    }
    .case-card {
      background: var(--card);
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      break-inside: avoid;
      margin-bottom: 24px;
    }
    .case-card:hover {
      transform: translateY(-5px);
      box-shadow: var(--shadow-hover);
    }
    .case-img {
      width: 100%;
      display: block;
      aspect-ratio: 16 / 9;
      object-fit: cover;
    }
    /* FAQ */
    .faq-item {
      border-bottom: 1px solid var(--border);
      padding: 16px 0;
    }
    .faq-question {
      font-weight: 600;
      font-size: 1.1rem;
      color: var(--primary);
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      transition: 0.2s;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      color: #495057;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      margin-top: 12px;
    }
    .faq-item.active i {
      transform: rotate(180deg);
    }
    /* 计数器 */
    .stat-number {
      font-size: 2.8rem;
      font-weight: 700;
      color: var(--accent);
    }
    footer {
      background: var(--primary);
      color: #e9ecef;
    }