/* Knowledge base design */
/* === ARTICLE LAYOUT === */
    .kb-art-hero {
      padding: 8rem 0 var(--space-lg);
      position: relative;
    }
    .kb-art-hero::before {
      content: '';
      position: absolute;
      top: 0; left: 0; right: 0;
      height: 400px;
      background: radial-gradient(ellipse 80% 60% at 50% 0%, rgba(232,90,28,0.04), transparent);
      pointer-events: none;
    }
    .kb-breadcrumb {
      display: flex;
      align-items: center;
      gap: 8px;
      font-size: 0.8125rem;
      color: var(--text-muted);
      margin-bottom: var(--space-lg);
    }
    .kb-breadcrumb a {
      color: var(--text-secondary);
      text-decoration: none;
      transition: color 0.2s var(--ease);
    }
    .kb-breadcrumb a:hover { color: var(--text-primary); }
    .kb-breadcrumb svg { width: 14px; height: 14px; opacity: 0.4; }

    .kb-art-grid {
      display: grid;
      grid-template-columns: 1fr 340px;
      gap: var(--space-xl);
      align-items: start;
    }

    /* Article body */
    .kb-art-body {
      position: relative;
      z-index: 1;
    }
    .kb-art-body .section-title {
      margin-bottom: var(--space-sm);
    }
    .kb-art-intro {
      font-size: 1.0625rem;
      color: var(--text-secondary);
      line-height: 1.72;
      margin-bottom: var(--space-xl);
      max-width: 640px;
    }

    .kb-block {
      background: var(--bg-card);
      border: 1px solid var(--border);
      border-radius: var(--radius-lg);
      padding: var(--space-md);
      margin-bottom: var(--space-md);
    }
    .kb-block h2 {
      font-size: 1.0625rem;
      font-weight: 600;
      margin-bottom: var(--space-sm);
    }
    .kb-block p {
      color: var(--text-secondary);
      font-size: 0.9375rem;
      line-height: 1.65;
    }
    .kb-block-list {
      margin: 0;
      padding: 0;
      list-style: none;
      display: grid;
      gap: 0.65rem;
    }
    .kb-block-list li {
      display: flex;
      align-items: flex-start;
      gap: 0.65rem;
      color: var(--text-secondary);
      font-size: 0.9375rem;
      line-height: 1.55;
    }
    .kb-block-list li::before {
      content: '';
      width: 6px;
      height: 6px;
      border-radius: 50%;
      background: var(--accent);
      flex-shrink: 0;
      margin-top: 0.55rem;
    }

    /* Sidebar */
    .kb-sidebar {
      position: sticky;
      top: 5.5rem;
      display: flex;
      flex-direction: column;
      gap: var(--space-md);
    }
    .kb-sidebar-section {
      background: var(--bg-card);
      border: 1px solid var(--border);
      border-radius: var(--radius-lg);
      padding: var(--space-md);
    }
    .kb-sidebar-section h3 {
      font-size: 0.9375rem;
      font-weight: 600;
      margin-bottom: var(--space-sm);
    }
    .kb-sidebar-links {
      display: grid;
      gap: 0.5rem;
    }
    .kb-sidebar-link {
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 0.75rem;
      text-decoration: none;
      padding: 0.65rem 0.85rem;
      border-radius: var(--radius-md);
      background: var(--bg-primary);
      border: 1px solid var(--border);
      color: var(--text-primary);
      font-size: 0.875rem;
      font-weight: 500;
      transition: border-color 0.2s var(--ease), background 0.2s;
    }
    .kb-sidebar-link:hover {
      border-color: var(--border-hover);
      background: var(--bg-elevated);
    }
    .kb-sidebar-link svg {
      width: 14px;
      height: 14px;
      color: var(--text-muted);
      flex-shrink: 0;
      transition: color 0.2s;
    }
    .kb-sidebar-link:hover svg { color: var(--accent); }
    .kb-sidebar-actions {
      display: flex;
      flex-direction: column;
      gap: var(--space-xs);
    }
    .kb-sidebar-actions .btn {
      width: 100%;
      justify-content: center;
    }

    /* Back link */
    .kb-back {
      display: inline-flex;
      align-items: center;
      gap: 0.5rem;
      margin-top: var(--space-lg);
      font-size: 0.875rem;
      font-weight: 500;
      color: var(--accent);
      text-decoration: none;
      transition: gap 0.2s var(--ease);
    }
    .kb-back:hover { gap: 0.75rem; }
    .kb-back svg { width: 14px; height: 14px; }

    /* Responsive */
    @media (max-width: 1024px) {
      .kb-art-grid {
        grid-template-columns: 1fr;
      }
      .kb-sidebar {
        position: static;
      }
    }
    @media (max-width: 768px) {
      .kb-art-hero {
        padding: 6.5rem 0 var(--space-md);
      }
    }

/* === KNOWLEDGE HERO === */
    .kb-hero {
      padding: 8rem 0 calc(var(--space-2xl) + var(--space-sm));
      position: relative;
    }
    .kb-hero::before {
      content: '';
      position: absolute;
      top: 0; left: 0; right: 0;
      height: 500px;
      background: radial-gradient(ellipse 80% 60% at 50% 0%, rgba(232,90,28,0.04), transparent);
      pointer-events: none;
    }
    .kb-hero-grid {
      display: grid;
      grid-template-columns: 1.3fr 1fr;
      gap: var(--space-xl);
      align-items: center;
    }
    .kb-hero-content {
      position: relative;
      z-index: 1;
    }
    .kb-hero-content p {
      color: var(--text-secondary);
      font-size: 1.0625rem;
      line-height: 1.72;
      margin-bottom: var(--space-lg);
      max-width: 520px;
    }
    .kb-hero-actions {
      display: flex;
      gap: var(--space-sm);
      flex-wrap: wrap;
    }
    .kb-hero-aside {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: var(--space-sm);
    }
    .kb-stat {
      background: var(--bg-card);
      border: 1px solid var(--border);
      border-radius: var(--radius-lg);
      padding: var(--space-md);
      transition: border-color 0.2s var(--ease);
    }
    .kb-stat:hover {
      border-color: var(--border-hover);
    }
    .kb-stat-num {
      font-size: 1.75rem;
      font-weight: 600;
      color: var(--text-primary);
      line-height: 1;
      margin-bottom: 0.35rem;
    }
    .kb-stat-num span {
      color: var(--accent);
    }
    .kb-stat-label {
      font-size: 0.8125rem;
      color: var(--text-muted);
    }

    /* === ARTICLES GRID === */
    .kb-section {
      padding-top: var(--space-xl);
      padding-bottom: var(--space-2xl);
    }
    .kb-section + .kb-section {
      padding-top: calc(var(--space-xl) + var(--space-sm));
    }
    .kb-articles {
      display: grid;
      grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
      gap: var(--space-md);
    }
    .kb-article {
      display: flex;
      flex-direction: column;
      background: var(--bg-card);
      border: 1px solid var(--border);
      border-radius: var(--radius-lg);
      padding: var(--space-md);
      text-decoration: none;
      transition: all 0.25s var(--ease);
      height: 100%;
    }
    .kb-article:hover {
      border-color: var(--border-hover);
      transform: translateY(-2px);
    }
    .kb-article-icon {
      width: 44px;
      height: 44px;
      background: var(--accent-subtle);
      border-radius: var(--radius-md);
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: var(--space-sm);
      flex-shrink: 0;
    }
    .kb-article-icon svg {
      width: 22px;
      height: 22px;
      color: var(--accent);
    }
    .kb-article-tag {
      font-size: 0.6875rem;
      font-weight: 500;
      text-transform: uppercase;
      letter-spacing: 0.04em;
      color: var(--text-muted);
      margin-bottom: 0.5rem;
    }
    .kb-article-title {
      font-size: 1.0625rem;
      font-weight: 600;
      color: var(--text-primary);
      margin-bottom: 0.5rem;
      line-height: 1.35;
    }
    .kb-article-desc {
      font-size: 0.9375rem;
      color: var(--text-secondary);
      line-height: 1.6;
      flex: 1;
    }
    .kb-article-footer {
      display: flex;
      align-items: center;
      gap: 0.3rem;
      margin-top: var(--space-md);
      padding-top: var(--space-sm);
      border-top: 1px solid var(--border);
      font-size: 0.875rem;
      font-weight: 500;
      color: var(--accent);
      transition: gap 0.2s var(--ease);
    }
    .kb-article:hover .kb-article-footer {
      gap: 0.6rem;
    }
    .kb-article-footer svg {
      width: 14px;
      height: 14px;
    }

    /* === HOW TO USE === */
    .kb-guide {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: var(--space-md);
    }
    .kb-guide-step {
      background: var(--bg-card);
      border: 1px solid var(--border);
      border-radius: var(--radius-lg);
      padding: var(--space-md);
    }
    .kb-guide-num {
      display: flex;
      align-items: center;
      justify-content: center;
      width: 32px;
      height: 32px;
      border-radius: var(--radius-sm);
      background: var(--accent);
      color: white;
      font-weight: 600;
      font-size: 0.875rem;
      margin-bottom: var(--space-sm);
    }
    .kb-guide-title {
      font-size: 0.9375rem;
      font-weight: 600;
      margin-bottom: 0.25rem;
    }
    .kb-guide-text {
      font-size: 0.875rem;
      color: var(--text-secondary);
      line-height: 1.6;
    }

    /* === RESPONSIVE === */
    @media (max-width: 1024px) {
      .kb-hero-grid {
        grid-template-columns: 1fr;
        gap: var(--space-lg);
      }
      .kb-guide {
        grid-template-columns: repeat(2, 1fr);
      }
    }
    @media (max-width: 768px) {
      .kb-hero {
        padding: 6.5rem 0 var(--space-xl);
      }
      .kb-section {
        padding-top: var(--space-lg);
      }
      .kb-section + .kb-section {
        padding-top: var(--space-xl);
      }
      .kb-hero-aside {
        grid-template-columns: 1fr 1fr;
      }
      .kb-articles {
        grid-template-columns: 1fr;
      }
      .kb-guide {
        grid-template-columns: 1fr;
      }
      .kb-hero-actions {
        flex-direction: row;
      }
    }
    @media (max-width: 480px) {
      .kb-hero-aside {
        grid-template-columns: 1fr;
      }
    }