halloween.js

Install guide · Shopify

Add Halloween effects to Shopify

On Shopify the script goes into your theme's main layout file. Use the snippet below as it is: it adds the classes to the existing <body> tag instead of replacing it, so your theme's own body classes stay intact.

Steps

  1. In the admin open Online Store → Themes, then Edit code on your live theme.

  2. Open Layout → theme.liquid.

  3. Paste the snippet just above the closing </body> tag 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>

Install once, then leave it. The effects switch on by themselves every year from 18 October to 2 November and stay off the rest of the time. There is nothing to remove afterwards. Installed earlier? You will see nothing until 18 October. That is expected, not a bug.

Check that it works

  1. Open your live site in a private window and reload without cache.

  2. Between 18 October and 2 November you should see webs in the screen corners and eyes blinking within a few seconds. Outside those dates the page looks unchanged.

Good to know

  • Want to test outside the season? Open the playground, set the active season to cover today and copy the snippet it generates.
  • 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.
  • Duplicate the theme first if you want to test on an unpublished copy before the live one.
  • Nothing showing in season? See troubleshooting.