blow/static/js/main.js

document.addEventListener("DOMContentLoaded", function() {
  // ---------------- Selected Navbar Link -------------------------
  let navbar_links = document.querySelector('#nav-links').children;
  let current_location = window.location.href;
  let selected_navbar_link = [...navbar_links].find((item) => {
    return (item.href === current_location)
  })
  selected_navbar_link.className = "bg-gray-900 text-white px-3 py-2 rounded-md text-sm font-medium"

  // ---------------- Switch Theme -------------------------
  // On page load or when changing themes, best to add inline in `head` to avoid FOUC
  if (localStorage.theme === 'dark' || (!('theme' in localStorage) && window.matchMedia('(prefers-color-scheme: dark)').matches)) {
    document.documentElement.classList.add('dark')
  } else {
    document.documentElement.classList.remove('dark')
  }
  // Switch theme action
  document.getElementById('switch-theme').addEventListener('click', switchTheme(), false);
});

function switchTheme() {
  console.log("called")
  let current_theme = ([...document.documentElement.classList].includes('dark')) ? 'dark' : 'light';
  if (current_theme === 'dark') {
    localStorage.theme = 'light'
    document.documentElement.classList.remove('dark')
  } else {
    localStorage.theme = 'dark'
    document.documentElement.classList.add('dark')
  }
}