你能帮我吗...我有这个代码，我想把它添加到localStorage任何解决方案

const sun = 'sun';
const moon = 'moon';
const toggleSwitch = document.querySelector('#darkmodeToggle');

function switchTheme(e) {
  if (document.documentElement.getAttribute('data-theme') == 'light') {
    document.documentElement.setAttribute('data-theme', 'dark');
    this.innerHTML = sun;
  }
  else {
    document.documentElement.setAttribute('data-theme', 'light');
    this.innerHTML = moon;
  }    
}
toggleSwitch.addEventListener('click', switchTheme, false);

if(window.matchMedia('(prefers-color-scheme: light)').matches) {
  document.documentElement.setAttribute('data-theme', 'light');
  toggleSwitch.innerHTML = moon;
}