body {
    margin: 0;
}

circle:hover {
    cursor: pointer;
}

* {
    font-family: -apple-system, BlinkMacSystemFont, sans-serif;
    color: #f5f5f7;
    background-color: #111;
}

input {
    border: 1px solid #f5f5f7;
    border-radius: 10px;
}

/* SVG parts */
text{
    -webkit-user-select: none; /* Safari         */
    -moz-user-select: none;    /* Firefox */
    -ms-user-select: none;     /* IE10+/Edge */
    user-select: none;         /* Standard */
    font-size: 12px;
    font-weight: bold;
    font-family: 'Courier New', Courier, monospace;
    fill: white;
  }
  
line {
    stroke: #555;
    stroke-width: 3px;
}