如何在单击时用圆圈填充按钮背景

<button id="myButton">点击按钮</button>

#myButton {
  background-color: #ffffff;
  border: 1px solid #000000;
  border-radius: 50%;
  width: 100px;
  height: 100px;
}

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

myButton.addEventListener("click", function() {
  myButton.classList.add("clicked");
  
  setTimeout(function() {
    myButton.classList.remove("clicked");
  }, 500);
});

#myButton.clicked {
  background-color: #ff0000;
}