.cluster-blue{background:radial-gradient(circle at 30% 30%,#64b5f6,#1565c0);color:#fff;border-radius:50%;width:44px;height:44px;display:flex;align-items:center;justify-content:center;font-weight:700;font-size:14px;box-shadow:0 0 0 4px rgba(21,101,192,.35);border:2px solid #0d47a1}