.custom-cluster {
    background: transparent;
}

.cluster-icon {
    width: 40px;
    height: 40px;
    background-color: #0073aa;
    color: white;
    border-radius: 50%;
    border: 3px solid white;
    box-shadow: 0 2px 6px rgba(0,0,0,0.4);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
    font-size: 14px;
}