var image = new Array(); 

//image[0] = 'imgs/valerio_bkg1.png' ; 
//image[1] = 'imgs/valerio_bkg2.png' ; 
//image[2] = 'imgs/valerio_bkg3.png' ; 
image[0] = 'imgs/valerio_bkg10_01.png' ; 
image[1] = 'imgs/valerio_bkg10_02.png' ; 
image[2] = 'imgs/valerio_bkg10_03.png' ; 
//image[3] = 'imgs/valerio_bkg10_04.png' ; 
image[3] = 'imgs/valerio_bkg10_05.png' ; 


var index = Math.floor(Math.random() * image.length); 
document.write('<style type="text/css"> table.title { background-image: url('+ image[index] +') } </style>');