使用单选按钮更改输入文本的bg颜色

<input type="radio" name="color" value="red">红色
<input type="radio" name="color" value="blue">蓝色
<input type="radio" name="color" value="green">绿色

var radios = document.getElementsByName("color");
for (var i = 0; i < radios.length; i++) {
  radios[i].addEventListener("change", function() {
    var selectedColor = document.querySelector('input[name="color"]:checked').value;
    document.getElementById("inputText").style.backgroundColor = selectedColor;
  });
}

<input type="text" id="inputText">