var imageData = [
	{
		src : 'images/index_il001.jpg',
		alt : 'Quality for the customer'
	},
	{
		src : 'images/index_il002.jpg',
		alt : 'Quality for the customer'
	},
	{
		src : 'images/index_il003.jpg',
		alt : 'Quality for the customer'
	},
	{
		src : 'images/index_il004.jpg',
		alt : 'Quality for the customer'
	}
];

function randomTopImage (id){
	if(!document.getElementById || !document.getElementById(id)) return;
	var el = document.getElementById(id);
	var n = Math.floor(Math.random() * imageData.length);

	el.src = imageData[n].src;
	el.alt = imageData[n].alt;
}