如何设置基于按钮点击的模式显示内容？

<button id="showButton">点击显示内容</button>
<div id="contentContainer"></div>

#showButton {
  padding: 10px;
  background-color: #007bff;
  color: #fff;
  border: none;
  cursor: pointer;
}

#contentContainer {
  display: none;
  padding: 20px;
  background-color: #f1f1f1;
}

var showButton = document.getElementById("showButton");
var contentContainer = document.getElementById("contentContainer");

showButton.addEventListener("click", function() {
  if (contentContainer.style.display === "none") {
    contentContainer.style.display = "block";
  } else {
    contentContainer.style.display = "none";
  }
});