var randomnumber = Math.floor(Math.random() * 4); //random number between 0-3
	
switch (randomnumber) {
	case 0:
		document.write('<link rel="stylesheet" href="cms/styles/pink.css" />');
		break;
	case 1:
		document.write('<link rel="stylesheet" href="cms/styles/green.css" />');
		break;
	case 2:
		document.write('<link rel="stylesheet" href="cms/styles/orange.css" />');
		break;
	default:
		document.write('<link rel="stylesheet" href="cms/styles/blue.css" />');
		break;
}