@keyframes spin{from{transform: rotate(0deg)}to{transform: rotate(360deg)}}.slot-spinner{width: 32px;height: 32px;margin: 16px auto;border: 3px solid #e0e0e0;border-top-color: #1976d2;border-radius: 50%;animation: spin 1.2s linear infinite}vaadin-card.started{background: #e8f5e9}vaadin-card.not-started{background: white}.past-slot vaadin-card.not-started{background: #fff3e0}