topic Re: How to Add code (js, css, html)to a specific page in page editor? in CMS Development

How to Add code (js, css, html)to a specific page in page editor?

AzharBondi — Thu, 03 Aug 2023 12:13:30 GMT

Hi,

I created a custom module where it has enumeration logic

(1 > untill it reaches last line : 200 for example).

Using html, css and javascript to create numbers that appear vertically from top header of the page to bottom of the footer.

I would love to add this logic to the page I am working on only...
That's why the module code snipppet can't be added to the template.

so, to apply the code I have built within the custom module where could I paste it so I can see the changes applied?

I tried using the page editor> settings> advanced> Head HTML

but code seems to not work as intended there

Actually, I also tried pasting the custom module code snippet in the head hmtl and it's working partially > I have numbers appear but they stop before reaching the bottom of the footer.

Any clues on what can help please ?

Thanks in advance!
Best regards,
Azhar

Re: How to Add code (js, css, html)to a specific page in page editor?

Jaycee_Lewis — Fri, 04 Aug 2023 18:14:23 GMT

Hi, @AzharBondi 👋 Thanks for the interesting question. Based on your last comments, do you have any screenshots of how it's displaying, even if partially? This may help our community members to better understand your issues and how they can help.

Thank you! — Jaycee

Re: How to Add code (js, css, html)to a specific page in page editor?

mudasir_qayyum — Mon, 15 Sep 2025 13:08:13 GMT

You can usually handle this in a couple of ways depending on whether you want the logic to run only on one page or across multiple templates:

Using Page-Specific Code Injection
In HubSpot, when you add code in the page editor under Settings → Advanced → Head/Body HTML, it only applies to that single page. For JavaScript that manipulates the DOM (like your vertical enumeration), you’ll often want to place it in the Footer HTML section instead of the Head. This way the script runs after the full page has rendered, so it can properly calculate the height and reach the footer.
Adjusting Script Logic
If the numbers stop before the footer, it’s likely the script is calculating height before all elements are loaded. Wrapping your code in a window.onload or using a MutationObserver can fix that so it runs after the page is fully ready.
Custom Module Placement
If you want tighter control, you can also drag your custom module directly onto the page in the content editor. Even if the module has custom HTML/JS, HubSpot will only render it on that page if you don’t add it to a template.

For a practical walkthrough on handling page-level CSS/JS in HubSpot, resource.