我有3个div，每个div都有自己的主题，现在我想让每个div打开它的模式

<div id="div1">
  <h2>主题1</h2>
  <!-- div1的内容 -->
</div>

<div id="div2">
  <h2>主题2</h2>
  <!-- div2的内容 -->
</div>

<div id="div3">
  <h2>主题3</h2>
  <!-- div3的内容 -->
</div>

// 获取div元素
var div1 = document.getElementById("div1");
var div2 = document.getElementById("div2");
var div3 = document.getElementById("div3");

// 初始化div的显示状态
div1.style.display = "block";
div2.style.display = "none";
div3.style.display = "none";

// 定义函数，用于切换div的显示状态
function switchDiv(div) {
  div1.style.display = "none";
  div2.style.display = "none";
  div3.style.display = "none";
  
  div.style.display = "block";
}

// 绑定事件，当点击div时切换显示状态
div1.addEventListener("click", function() {
  switchDiv(div1);
});

div2.addEventListener("click", function() {
  switchDiv(div2);
});

div3.addEventListener("click", function() {
  switchDiv(div3);
});