halloween.js / WordPress

Add Halloween effects to WordPress

A header and footer code plugin is the simplest way to add the script to any WordPress or WooCommerce site, with no theme files to edit. It works with classic and block themes alike.

Steps

Install a plugin that injects code into the header or footer, for example WPCode, and activate it.
Open the plugin's header and footer settings. In WPCode that is Code Snippets → Header & Footer.
Paste the snippet below into the Footer field and save.

The snippet

One paste, no other files. It loads halloween.js 1.0.3 from jsDelivr and turns on webs in two corners, blinking eyes, flying witches, a dropping spider and a rising tombstone.

<script src="https://cdn.jsdelivr.net/npm/halloween.js@1.0.3/dist/halloween.iife.js"></script>
<script>
(function () {
  function apply() {
    document.body.classList.add("halloween", "halloween-screen-left-top", "halloween-screen-right-bottom", "halloween-eyes", "halloween-witches", "halloween-spider-drop", "halloween-tombstones");
  }
  if (document.readyState === "loading") {
    document.addEventListener("DOMContentLoaded", apply);
  } else {
    apply();
  }
})();
</script>

Make it yours

Pick corners, effects, intensity, color and season dates in the playground and open the Paste-only tab. It produces this same snippet, library line included, with your choices.

Good to know

The effects only appear in a window around Halloween, 18 October to 2 November by default. Change the dates in the playground to see them on another day.
Ambient effects stop when a visitor has reduced motion turned on. The screen-corner webs stay.
The effects sit in a fixed layer and never shift your page layout.
Prefer a child theme? Put the same snippet into a wp_footer hook in the child theme's functions.php instead of using a plugin.
Nothing showing? Reload without cache, then check that the snippet is on the live site and that no content blocker is stripping it.

Other platforms

All options on the halloween.js home page, full documentation on GitHub.