function random_bg_color() { var x = Math.floor(Math.random() * 256); var y = Math.floor(Math.random() * 256); var z = Math.floor(Math.random() * 256); var bgColor = "rgb(" + x + "," + y + "," + z + ")"; console.log(bgColor); document.body.style.background = bgColor; } random_bg_color();