/* roulang page: index */
/* 基础重置与设计变量 */
    :root {
      --color-dark: #1A1A1A;
      --color-gray: #F2F2F2;
      --color-red: #E85D3F;
      --color-red-dark: #C94A2F;
      --text-primary: #1A1A1A;
      --text-soft: #4A4A4A;
      --text-muted: #8A8A8A;
      --border-light: #D1D1D1;
      --radius-card: 8px;
      --radius-btn: 6px;
      --radius-full: 40px;
    }

    body {
      font-family: 'PingFang SC', 'Microsoft YaHei', system-ui, -apple-system, sans-serif;
      background-color: #FFFFFF;
      color: var(--text-soft);
      line-height: 1.7;
      -webkit-font-smoothing: antialiased;
      box-sizing: border-box;
    }

    *, *::before, *::after {
      box-sizing: inherit;
    }

    /* 文字层级辅助 */
    .text-balance {
      text-wrap: balance;
    }

    /* 自定义滚动条（保持极简） */
    ::-webkit-scrollbar {
      width: 6px;
    }
    ::-webkit-scrollbar-track {
      background: #f1f1f1;
    }
    ::-webkit-scrollbar-thumb {
      background: #c1c1c1;
      border-radius: 3px;
    }

    /* 导航浮动Dock */
    .nav-dock {
      background: rgba(255, 255, 255, 0.92);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      border-radius: var(--radius-full);
      padding: 8px 24px;
      box-shadow: 0 2px 16px rgba(0,0,0,0.06);
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: 1280px;
      margin: 24px auto 0;
      position: sticky;
      top: 24px;
      z-index: 50;
      width: calc(100% - 40px);
      transition: all 0.2s ease;
    }

    /* 卡片hover效果 */
    .card-hover {
      transition: transform 0.25s ease, box-shadow 0.25s ease;
      border-radius: var(--radius-card);
      box-shadow: 0 4px 20px rgba(0,0,0,0.04);
    }
    .card-hover:hover {
      transform: translateY(-2px);
      box-shadow: 0 8px 30px rgba(0,0,0,0.08);
    }

    /* 作品图片缩放与遮罩 */
    .work-img-wrapper {
      overflow: hidden;
      border-radius: var(--radius-card);
      position: relative;
    }
    .work-img-wrapper img {
      transition: transform 0.3s ease;
      display: block;
      width: 100%;
      height: auto;
    }
    .card-hover:hover .work-img-wrapper img {
      transform: scale(1.03);
    }
    .img-overlay {
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background: rgba(232, 93, 63, 0.85);
      color: white;
      display: flex;
      align-items: center;
      justify-content: center;
      opacity: 0;
      transition: opacity 0.3s ease;
      font-weight: 600;
      font-size: 1.1rem;
      letter-spacing: 0.5px;
      pointer-events: none;
    }
    .card-hover:hover .img-overlay {
      opacity: 1;
    }

    /* FAQ 手风琴动画 */
    .faq-content {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    }
    .faq-item.active .faq-content {
      max-height: 200px; /* 足够容纳回答 */
    }
    .faq-arrow {
      transition: transform 0.3s ease;
    }
    .faq-item.active .faq-arrow {
      transform: rotate(180deg);
    }

    /* 表单动效 */
    .input-line {
      border-bottom: 1px solid var(--border-light);
      transition: border-color 0.2s, border-width 0.2s;
    }
    .input-line:focus {
      outline: none;
      border-bottom: 2px solid var(--color-red);
    }

    /* 浮动标签动画 */
    @keyframes float {
      0% { transform: translateY(0px); }
      50% { transform: translateY(-6px); }
      100% { transform: translateY(0px); }
    }
    .float-tag {
      animation: float 3s ease-in-out infinite;
    }

    @media (max-width: 768px) {
      .nav-dock {
        position: fixed;
        bottom: 20px;
        top: auto;
        left: 20px;
        right: 20px;
        width: auto;
        margin: 0;
        border-radius: 40px;
        padding: 8px 20px;
        justify-content: space-around;
        background: rgba(26, 26, 26, 0.94);
        backdrop-filter: blur(20px);
        color: white;
        box-shadow: 0 4px 20px rgba(0,0,0,0.2);
        z-index: 60;
      }
      .nav-dock .logo-text {
        color: white !important;
      }
      .nav-dock a {
        color: #cccccc !important;
      }
      .nav-dock .btn-primary-mobile {
        background: #E85D3F;
        color: white !important;
        padding: 6px 14px;
        border-radius: 20px;
      }
      .desktop-only {
        display: none !important;
      }
      .mobile-only {
        display: block !important;
      }
    }

    @media (min-width: 769px) {
      .mobile-only {
        display: none !important;
      }
    }

    /* 对比区块虚线 */
    .comparison-divider {
      border-left: 1px dashed #D1D1D1;
      height: auto;
      margin: 0 2rem;
    }