html,
body {
  height: 100%;
  margin: 0;
}

body {
  cursor: pointer;
}

.container {
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100%;
}

#score {
  position: absolute;
  top: 16px;
  right: 16px;
  font-size: 8em;
  font-weight: 256;
}

#introduction {
  width: 256px;
  height: 128px;
  position: absolute;
  font-weight: 512;
  font-size: 1em;
  text-align: center;
  transition: opacity 1s;
}

#restart {
  width: 128px;
  height: 128px;
  position: absolute;
  border-radius: 100%;
  color: rgb(75, 156, 8);
  background-color: rgb(3, 55, 114);
  border: none;
  font-weight: 256;
  font-size: 2em;
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  display: none;
  cursor: pointer;
}

#perfect {
  position: absolute;
  opacity: 0;
  transition: opacity 3s;
}