.hub-app{max-width:1200px;margin:0 auto;padding:40px 20px}.hub-header{text-align:center;margin-bottom:60px}.back-link{color:var(--text-secondary);margin-bottom:20px;font-weight:500;text-decoration:none;transition:color .2s;display:inline-block}.back-link:hover{color:var(--text-primary)}.hub-header h1{color:var(--text-primary);margin-bottom:16px;font-size:2.5rem}.hub-header p{color:var(--text-secondary);max-width:600px;margin:0 auto;font-size:1.1rem}.tool-category{margin-bottom:48px}.tool-category h2{color:var(--text-primary);border-bottom:2px solid var(--border-color);margin-bottom:24px;padding-bottom:8px;font-size:1.5rem}.tools-grid{grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:24px;display:grid}.tool-card{background:var(--bg-panel);border:1px solid var(--border-color);border-radius:var(--radius-lg);color:var(--text-primary);transition:all var(--transition-fast);box-shadow:var(--shadow-sm);flex-direction:column;gap:12px;padding:24px;text-decoration:none;display:flex}.tool-card:hover{box-shadow:var(--shadow-md);border-color:var(--border-focus);transform:translateY(-4px)}.tool-card.disabled{opacity:.6;cursor:not-allowed;pointer-events:none}.tool-card h3{color:var(--primary-color);margin:0;font-size:1.25rem;font-weight:600}.tool-card p{color:var(--text-secondary);margin:0;font-size:.95rem;line-height:1.5}