halloween.js / 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

In the admin open Online Store → Themes, then Edit code on your live theme.
Open Layout → theme.liquid.
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>

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.
Duplicate the theme first if you want to test on an unpublished copy before the live one.
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.