function rdlink(){
	var totalfolders = 5; /*numero delle directory*/
	var folder = new Array (totalfolders);
	folder[0] = {name:'flyer', arr:['0','1','2','3','4','5','6','7','8','9','10','11','12','13','14','15','16','17','18']}; /*name:nome della dyrectory  arr: pagine contenute partendo da 0*/
	folder[1] = {name:'pack', arr:['0','1','2','3','4','5','6','7','8','9']};
	folder[2] = {name:'logos', arr:['0','1','2','3','4','5','6','7']};
	folder[3] = {name:'photos', arr:['0','1','2','3','4','5','6','7','8','9','10','11','12','13','14']};
	folder[4] = {name:'web', arr:['0','1','2','3','4','5','6','7','8','9','10','11','12','13','14','15','16']};
	var linkR = Math.floor(Math.random()*totalfolders);
	var pageR = Math.floor(Math.random()*folder[linkR].arr.length);
	document.location = '/' + folder[linkR].name + '/file' + pageR + '.shtml';
}

var contheight = 395;
function centerV(alt) {
	document.getElementById('img').style.marginTop = (contheight - alt )/2+ 'px';
}