:root {
      --color-primary: #1E3A5F;
      --color-secondary: #2C3E50;
      --color-accent: #3498DB;
      --color-accent-light: #E8F4FC;
      --color-background: #F8FAFC;
      --color-surface: #FFFFFF;
      --color-border: #E1E8ED;
      --shadow-sm: 0 1px 4px rgba(30,58,95,0.06);
      --shadow-md: 0 2px 12px rgba(30,58,95,0.1);
      --shadow-lg: 0 4px 24px rgba(30,58,95,0.15);
      --radius-sm: 4px;
      --radius-md: 8px;
      --radius-lg: 12px;
      --transition: cubic-bezier(0.4, 0, 0.2, 1);
    }
    * { margin: 0; padding: 0; box-sizing: border-box; }
    html { scroll-behavior: smooth; }
    body { font-family: 'Noto Sans SC', sans-serif; background: var(--color-background); color: var(--color-secondary); line-height: 1.6; overflow-x: hidden; }

    .navbar { border-bottom: 1px solid var(--color-border); }
    .logo { display: flex; align-items: center; gap: 8px; }
    .menu-overlay { background: rgba(30,58,95,0.2); }

    .breadcrumb { margin-top: 64px; padding: 16px 20px; max-width: 1200px; margin-left: auto; margin-right: auto; font-size: 0.875rem; color: var(--color-secondary); }
    .breadcrumb a { color: var(--color-secondary); text-decoration: none; transition: color 0.3s; }
    .breadcrumb a:hover { color: var(--color-accent); }
    .breadcrumb span { margin: 0 8px; }

    .product-detail { margin-top: 64px; padding: 0 20px 60px; max-width: 1200px; margin-left: auto; margin-right: auto; }
    .detail-grid { display: grid; gap: 40px; }
    .detail-image { aspect-ratio: 1; background: linear-gradient(135deg, #E8F0F8 0%, #F0F5FA 100%); border-radius: var(--radius-lg); display: flex; align-items: center; justify-content: center; font-size: 8rem; position: relative; overflow: hidden; }
    .detail-info { display: flex; flex-direction: column; gap: 20px; }
    .detail-tag { display: inline-block; padding: 6px 16px; background: var(--color-accent); color: white; font-size: 0.75rem; font-weight: 500; border-radius: var(--radius-sm); width: fit-content; }
    .detail-title { font-size: clamp(1.5rem, 4vw, 2rem); font-weight: 600; line-height: 1.3; color: var(--color-primary); }
    .detail-price { font-family: 'DM Sans', sans-serif; font-size: 2rem; font-weight: 700; color: var(--color-accent); }
    .detail-desc { color: var(--color-secondary); line-height: 1.8; }
    .detail-specs { background: var(--color-surface); border-radius: var(--radius-md); padding: 20px; box-shadow: var(--shadow-sm); border: 1px solid var(--color-border); }
    .detail-specs h4 { font-size: 1rem; margin-bottom: 12px; color: var(--color-primary); }
    .spec-list { list-style: none; }
    .spec-list li { display: flex; justify-content: space-between; padding: 8px 0; border-bottom: 1px solid var(--color-border); font-size: 0.9rem; }
    .spec-list li:last-child { border-bottom: none; }
    .spec-list .spec-label { color: var(--color-secondary); }
    .spec-list .spec-value { font-weight: 500; }
    .detail-actions { display: flex; gap: 12px; margin-top: 8px; }
    .btn-primary { flex: 1; padding: 16px 32px; background: var(--color-primary); color: white; border: none; border-radius: var(--radius-sm); font-size: 1rem; font-weight: 500; cursor: pointer; transition: all 0.3s var(--transition); }
    .btn-primary:hover { background: var(--color-accent); transform: translateY(-2px); }
    .btn-secondary { padding: 16px 24px; background: var(--color-surface); color: var(--color-primary); border: 1px solid var(--color-border); border-radius: var(--radius-sm); font-size: 1rem; cursor: pointer; transition: all 0.3s var(--transition); }
    .btn-secondary:hover { border-color: var(--color-accent); color: var(--color-accent); }

    .related-section { padding: 60px 20px; background: var(--color-surface); }
    .related-title { font-size: 1.5rem; font-weight: 600; text-align: center; margin-bottom: 32px; color: var(--color-primary); }
    .related-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 16px; max-width: 1200px; margin: 0 auto; }
    .related-card { background: var(--color-background); border-radius: var(--radius-md); padding: 20px; text-decoration: none; color: inherit; transition: all 0.3s var(--transition); display: block; border: 1px solid var(--color-border); }
    .related-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); border-color: var(--color-accent); }
    .related-img { aspect-ratio: 1; background: linear-gradient(135deg, #F4F7FA, #EDF2F7); border-radius: var(--radius-sm); display: flex; align-items: center; justify-content: center; font-size: 2.5rem; margin-bottom: 12px; }
    .related-name { font-size: 0.9rem; font-weight: 500; margin-bottom: 4px; }
    .related-price { font-family: 'DM Sans', sans-serif; font-size: 1rem; font-weight: 700; color: var(--color-accent); }

    .footer { background: var(--color-primary); color: rgba(255,255,255,0.8); padding: 48px 20px 32px; }
    .footer-content { max-width: 800px; margin: 0 auto; text-align: center; }
    .footer-logo { font-size: 1.5rem; font-weight: 600; color: white; margin-bottom: 24px; letter-spacing: 0.05em; }
    .footer-links { display: flex; justify-content: center; flex-wrap: wrap; gap: 24px; margin-bottom: 32px; }
    .footer-links a { color: rgba(255,255,255,0.7); text-decoration: none; font-size: 0.9rem; }
    .footer-links a:hover { color: var(--color-accent); }
    .footer-divider { width: 60px; height: 1px; background: rgba(255,255,255,0.2); margin: 0 auto 24px; }
    .footer-copy { font-size: 0.85rem; opacity: 0.6; }

    @media (min-width: 768px) {
      .detail-grid { grid-template-columns: 1fr 1fr; gap: 60px; }
      .related-grid { grid-template-columns: repeat(4, 1fr); gap: 24px; }
      .product-detail { padding: 20px; }
    }

    .product-detail-body img,
    .product-detail-body video { max-width: 100%; height: auto; }
    .product-detail-body iframe { max-width: 100%; }

    .bottom-nav { display: none; position: fixed; bottom: 0; left: 0; right: 0; height: 60px; background: #FFFFFF; border-top: 1px solid var(--color-border); z-index: 1000; padding-bottom: env(safe-area-inset-bottom, 0); }
    .bottom-nav-inner { display: flex; justify-content: space-around; align-items: center; height: 100%; max-width: 500px; margin: 0 auto; }
    .bottom-nav-item { display: flex; flex-direction: column; align-items: center; gap: 4px; color: #999; text-decoration: none; font-size: 10px; transition: color 0.3s; background: none; border: none; cursor: pointer; padding: 8px 16px; }
    .bottom-nav-item.active, .bottom-nav-item:hover { color: var(--color-accent); }
    .bottom-nav-item .nav-icon { font-size: 20px; }
    .popover-overlay { position: fixed; inset: 0; background: rgba(30,58,95,0.5); z-index: 2000; opacity: 0; visibility: hidden; transition: all 0.3s; }
    .popover-overlay.show { opacity: 1; visibility: visible; }
    .popover-box { position: fixed; bottom: 70px; left: 50%; transform: translateX(-50%) translateY(20px); background: #FFFFFF; border-radius: var(--radius-md); padding: 24px; z-index: 2001; opacity: 0; visibility: hidden; transition: all 0.3s; text-align: center; box-shadow: var(--shadow-lg); border: 1px solid var(--color-border); }
    .popover-box.show { opacity: 1; visibility: visible; transform: translateX(-50%) translateY(0); }
    .popover-qr { width: 160px; height: 160px; background: var(--color-background); border-radius: var(--radius-sm); display: flex; align-items: center; justify-content: center; font-size: 60px; margin-bottom: 12px; border: 1px solid var(--color-border); }
    .popover-title { font-size: 14px; font-weight: 500; color: var(--color-primary); }
    .popover-tip { font-size: 12px; color: #999; margin-top: 4px; }

    @media (max-width: 768px) { .bottom-nav { display: block; } .footer { display: none; } .product-detail { padding-bottom: 80px; } body { padding-bottom: 60px; } .popover-box { bottom: 130px; } }
/* 底部导航自定义图片图标（后台可配置） */
.bottom-nav-item .nav-icon-img { width: 24px; height: 24px; object-fit: contain; vertical-align: middle; }