Javascript countdown

countdown.css

#countdown {
    position: absolute;
    left: 50%;
    top: 50%;
    width: 100px;
    height: 100px;
    display: none;
    margin: -50px 0 0 -50px;
    border: 2px solid #cecece;
    background-color: #fefefe;
    text-align: center;
    line-height: 100px;
    font-size: 60px;
    font-family: sans-serif;
}

countdown.html

<a id="startCountdown" href="#">Start</a>
<div id="countdown"></div>

countdown.js

function doCountdown() {
    var start = 1;
    var finish = 3;
    var message = "Go";
    var url = "http://google.com";
    var colors = [
    	"green", // 1
        "blue", // 2
        "orange", // 3
        "red"  // Go
    ];
    
    var element = document.getElementById("countdown");
    element.style.display = "block";
    
    var loopCountdown = function(count) {
        element.innerHTML = ''+count;
        element.style.color = colors[count-1];
        
		setTimeout(function() {
            console.log(count);
        	if(count < finish) {
            	loopCountdown(++count);
        	} else {
            	element.innerHTML = message;
                element.style.color = colors[colors.length - 1];
                window.location.replace(url);
        	}
		}, 1000);
    }
    
    loopCountdown(start);
}

document.getElementById("startCountdown").onclick = doCountdown;