Vanilla JS toggle

const span = document.querySelector("span");
let classes = span.classList;

span.addEventListener("click", function() {
  let result = classes.toggle("active");

  if (result) {
    console.log("active class was added");
  } else {
    console.log("active class was removed");
  }
});

Source

https://github.com/roeib/JavaScript-snippets#vanilla-js-toggle