// sets the background image on the container that appears in the bottom right of the page.
function refresh_image()
{
	var array_imgs = new Array("football.gif", "lady-reading.gif", "flying-kite.gif", "walking-dog.gif");
	var index = randomToN(array_imgs.length -1);
	
	document.getElementById("container").style.backgroundImage = "url(images/" + array_imgs[index] + ")";
}

// random number generator between 0 and maxVal
function randomToN(maxVal,floatVal)
{   var randVal = Math.random()*maxVal;   
    return typeof floatVal=='undefined'?Math.round(randVal):randVal.toFixed(floatVal);
}