By default, Giveaway Ninja provides a pop-up widget to run your giveaway.
To improve the user experience, you can easily create your own landing page and embed the giveaway on it!
A dedicated landing page has many benefits:
From your Shopify Admin, go to Online Store > Themes, then click Customize to open the theme editor.
In the theme editor, click on the PAGES dropdown at the top of the page.
Click on CREATE TEMPLATE to create a new page template for your giveaway.
Enter a template name (for example, "Giveaway Embed") and choose the page it should be based on - typically you'll select Default Page.

Click on Add Section in your new template.
Navigate to the Apps section and locate the "Giveaway Embed" app block.
Click on it to add it to your page template.

Open the Giveaway Ninja Campaign editor and click on GIVEAWAY.
Locate and copy your Giveaway ID from the Giveaway Details section.

Back in the theme editor, paste the Giveaway ID into the app block settings.
You can use the CUSTOM CSS section to fine-tune the block styling and appearance.
Use the Mobile Margin Adjustment setting to fine-tune the padding on mobile devices if needed.

Click Save to save your template.
Now go to Online Store > Pages and create a new page (or edit an existing one).
Under the template selection, choose your newly created template (e.g., "Giveaway Embed") to apply it to the page.
Edit your giveaway and make sure that all the shareable URLs lead to your landing page (ex. https://shop.com/pages/giveaway).
You may want to check: