3 Gradient Color Background

const css = document.getElementById("output");
const color1 = document.getElementById("color1");
const color2 = document.getElementById("color2");
const color3 = document.getElementById("color3");
const body = document.getElementById("gradient");

function setGradient() {
  body.style.background = `linear-gradient(to right, ${color1.value} ,${color2.value},${color3.value}`;
  css.value = `${body.style.background}`;
}

color1.addEventListener("input", setGradient);
color2.addEventListener("input", setGradient);
color3.addEventListener("input", setGradient);

website link: 3-Gradient-Color-Background