hugo-battheme/static/js/darkmode.js

const checkbox = document.getElementById("darkmode-toggle");
const colorswitchers = document.getElementsByClassName("colorswitch");

if (localStorage.getItem("light")) {
  switchToLight();
} else {
  switchToDark();
}
checkbox.checked = localStorage.getItem("dark");

checkbox.addEventListener("change", function () {
  localStorage.setItem("light", this.checked);
  if (this.checked) {
    switchToLight();
  } else {
    localStorage.removeItem("light");
    switchToDark();
  }
});

function switchToLight() {
  for (let item of colorswitchers) {
    item.classList.add("light");
  }
}

function switchToDark() {
  for (let item of colorswitchers) {
    console.log(item);
    item.classList.remove("light");
  }
}