选择一种颜色时显示文本框，同时隐藏另一种颜色

<label for="color">选择颜色:</label>
<select id="color" onchange="showHideTextbox()">
  <option value="red">红色</option>
  <option value="blue">蓝色</option>
</select>

<div id="textboxContainer">
  <label for="textbox">文本框:</label>
  <input type="text" id="textbox">
</div>

#textboxContainer {
  display: none;
}

function showHideTextbox() {
  var colorSelect = document.getElementById("color");
  var textboxContainer = document.getElementById("textboxContainer");

  if (colorSelect.value === "red") {
    textboxContainer.style.display = "block";
  } else {
    textboxContainer.style.display = "none";
  }
}