Uncaught TypeError: Cannot read property of undefined (reading ‘green’)

const mainebutton = document.querySelector("button");
const body = document.body;

function randomcolorgenerator() {
  const red = Math.floor(Math.random() * 256);
  const green = Math.floor(Math.random() * 256);
  const blue = Math.floor(Math.random() * 256);
  console.log(red, green, blue);
  const randomcolor = "rgb ${red},${green},${blue}";
  return randomcolor;
}
mainebutton.addEventListener("click", () => {
  const randomcolor = randomcolorgenerator();
  console.log(randomcolor);
});