如何在单击按钮时显示两种不同颜色的按钮

<button id="myButton">点击我</button>

.button-blue {
  background-color: blue;
  color: white;
}

.button-red {
  background-color: red;
  color: white;
}

var button = document.getElementById("myButton");

button.addEventListener("click", function() {
  if (button.classList.contains("button-blue")) {
    button.classList.remove("button-blue");
    button.classList.add("button-red");
  } else {
    button.classList.remove("button-red");
    button.classList.add("button-blue");
  }
});