选中单选按钮时无法隐藏文本框

<input type="radio" name="option" id="option1">选项1
<input type="text" id="textbox">

var option1 = document.getElementById("option1");
var textbox = document.getElementById("textbox");

option1.addEventListener("change", function() {
  if (option1.checked) {
    textbox.style.display = "block"; // 显示文本框
  } else {
    textbox.style.display = "none"; // 隐藏文本框
  }
});