Add toast JavaScript function

function createToast(heading = "No heading", message = "No message") {
  //Create empty variable for toasts container
  let container;
  //If container doesn't already exist create one
  if (!document.querySelector("#toast-holder")) {
    container = document.createElement("div")
    container.setAttribute("id", "toast-holder");
  } else {
    // If container exists asign it to a variable
    container = document.querySelector("#toast-holder");
  //Create our toast HTML and pass the variables heading and message
  let toast = `<div class="single-toast fade-in">
                  <div class="toast-header">
                    <span class="toast-heading">${heading}</span>
                    <a href="#" class="close-toast">X</a>
                  <div class="toast-content">
  // Once our toast is created add it to the container
  // along with other toasts
  container.innerHTML += toast;

createToast("This is heading", "This is the message");