body {
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
  margin: 0;
}

.piano {
  border: 1px solid #000;
  display: flex;
  justify-content: space-between;
  align-items: center;
  background-color: #fff;
  padding: 20px;
  user-select: none;
}

.key {
  background-color: #000;
  color: #fff;
  padding: 20px;
  margin: 0 10px;
  cursor: pointer;
}