body {
  margin: 0;
  overflow: hidden;
  background: #111;
  color: #fff;
  font-family: Poppins, sans-serif;
  text-align: center;
}

#score {
  position: absolute;
  top: 10px;
  left: 10px;
  font-size: 1.5em;
}

.target {
  width: 50px;
  height: 50px;
  background: radial-gradient(circle, red 40%, transparent 45%);
  border-radius: 50%;
  position: absolute;
  cursor: pointer;
  transition: transform 0.1s;
}

.target:active {
  transform: scale(0.8);
}