How to replace style with javascript that has already been set?

vusan

I’m implementing menu that is selected by the help of javascript. In jsfiddle.
Blocks are selected by the help of changing the style in innerHTML of div here.

But how to replace the style that has already been set?

Here my problem is I cannot select block 1.

full html code:

<style>
div {width:10px;height:10px;margin:10px;
    background:#ccc;cursor:pointer;padding:10px;
}
</style>
<div id="makeThatEnable" style="display:none"></div>

<div id="one" onclick="makeThisEnable(this.id)" style="border:1px solid #00f">1</div>
<div id="two" onclick="makeThisEnable(this.id)">2</div>
<div id="three" onclick="makeThisEnable(this.id)">3</div>
<div id="four" onclick="makeThisEnable(this.id)">4</div>
<div id="five" onclick="makeThisEnable(this.id)">5</div>
<br>
Click on box to select it.

<script>
function makeThisEnable(id) {
    document.getElementById('makeThatEnable').innerHTML="<style> #"+id+" {border:1px solid #f00}</style>";   
}
</script>