function onKonamiCode(callback: () => void): void {
  let input = "";
  const konami =
    "arrowuparrowuparrowdownarrowdownarrowleftarrowrightarrowleftarrowrightba";
  document.addEventListener("keydown", (e: KeyboardEvent) => {
    input = (input + e.key.toLowerCase()).slice(-konami.length);
    if (input === konami) callback();
  });
}

onKonamiCode(() => {
  document.body.classList.toggle("bg-black");
  document.body.classList.toggle("bg-white");
  const header = document.getElementById("header");
  header?.classList.toggle("text-white");
  header?.classList.toggle("text-black");
});