Reload CSS files without reloading the page

reloadCSS.js

function reloadCSS() {
  const links = document.getElementsByTagName('link');
  
  Array.from(links)
    .filter(link => link.rel.toLowerCase() === 'stylesheet' && link.href)
    .forEach(link => {
      const url = new URL(link.href, location.href);
      url.searchParams.set('forceReload', Date.now());
      link.href = url.href;
    });
}

You could use querySelectorAll('link[rel="stylesheet"]') to remove the need to filter()