var backgr1="fundo01"
var backgr2="fundo02"
var backgr3="fundo03"
var cur=Math.round(6*Math.random())
if (cur<=1)
backgr=backgr1
else if (cur<=4)
backgr=backgr2
else
backgr=backgr3
document.write('<body background="'+backgr+'" bgcolor="#FFFFFF">')
</script>