#diagram hr {
        background-color: #333;
      }

      #diagram > div {
        padding: .8em;
        margin: .1em;
        margin-bottom: 1em;
        text-align: center;
      }

      #diagram > div > span {
        border: 2px solid #333;
        margin: 1em;
        padding: .5em;
      }

      /* This hack centers the circle */
      #diagram > div:first-child {
        margin-left: 12em;
      }

      #circle {
        width: 6em;
        height: 6em;
        -moz-border-radius: 3em;
       