问为什么更改div内部的颜色不起作用？

EN

var div = document.getElementsByTagName("div");
var divCount = div.length;
var clickedDivId;

for (var i = 0; i < divCount; i += 1) {
    div[i].onclick = function(e) {
        if (e.target.id) alert(this.id);
		clickedDivId = this.id;
        e.stopPropagation();
    };
}  

function BackgroundColor(){
  var x = document.getElementsByClassName("backgroundcolor")[0].value;
  document.getElementById(clickedDivId).style.backgroundColor = x;
}

#divid{
  width: 450px;
  height: 170px;
  margin: 10px;
  padding: 10px;
  background-color: blue;
}
.divclass{
  width: 450px;
  height: 170px;
  margin: 10px;
  padding: 10px;
  background-color: blue;
}

<div  class="divclass">
     <input type="color" class="backgroundcolor" onchange="BackgroundColor()">
</div>
<div  id="divid"></div>