#timer {
  width: 460px;
  font-size: 70px;
  background-color: black;
  color: limegreen;
  padding: 25px;
  border-radius: 10px;
}
#labels {
  margin-top: -25px;
  z-index: 2;
  color: limegreen;
  font-size: 12px;
}
#hh {margin-left: 45px;}
#mm {margin-left: 80px;}
#ss {margin-left: 70px;}
#ms {margin-left: 45px;}

#controls {
  margin-left:150px;
  margin-top: 30px;
}

button {
  width: 100px;
  height: 40px;
  float: left;
  margin-left: 50px;
  font-size: 25px;
  font-weight: bold;
  border-radius: 10px;
  box-shadow: 5px 5px 5px #888888;
}
#go    { background-color: limegreen; }

#stop  { background-color: red;  display: none; }

#clear { background-color: yellow; display: none;}

body, button {
  font-family: 'Courier';
}