function changeClass(){
    var randomnumber = Math.floor(Math.random()*3);
    randomnumber = randomnumber + 1 ;
    //alert('option:' + randomnumber);
    
    if (randomnumber == 1) {
        var xmas = document.getElementById("xmas09");
        xmas.className = "content-body xmas1";
        //alert('triggerd 1');
        return;
    }
    
    else if (randomnumber == 2) {
        var xmas = document.getElementById("xmas09");
        xmas.className = "content-body xmas2";
        //alert('triggerd 2');
        return;
    }
    
    else if (randomnumber == 3) {
        var xmas = document.getElementById("xmas09");
        xmas.className = "content-body xmas3";
        //alert('triggerd 3');
        return;
    }
    
    else {
        var xmas = document.getElementById("xmas09");
        xmas.className = "content-body xmas2";
        //alert('triggerd else');
        return;
    }
}