#chart {width:100vw;height:100vh;}
#tooltip {position:absolute;padding:8px;background:#FFF;
border-radius:4px;box-shadow:0 2px 10px rgba(0,0,0,0.2);pointer-events:none;opacity:0;font-size:14px;max-width:300px;z-index:100;}
#tooltip a {color:#1a73e8;text-decoration:none;font-weight:bold;}
path {min-width:1px;min-height:1px;}
.center-circle {fill:#00000;cursor:pointer;transition:all 0.2s ease;}
.center-circle:hover {fill:#FF0000;stroke-width:1px;}
.center-label {cursor:pointer;user-select:none;}