var j = 0;
    function changeColor(){
        j++;
        switch(j){ 
           case 1:return "#04a1f1";
           case 2:return "green";
           case 3:return  "red";
           default:return "#04a1f1";
        }
    }

    function colorfull() {
         var t =document.getElementById('colortext')
         t.style.color=changeColor();
         if(j==3)j=0;
        setTimeout('colorfull()',500);
    }