Hello! We’re using Checkout Blocks to add a custom block with an image. We’d like to show different images on mobile vs. desktop; simple CSS. What’s the best way to inject this CSS through a custom app created in the Shopify Dev Dashboard? Ideally looking for the simplest and most maintainable met…

You cannot inject CSS into the checkout anymore. Please refer to the below link for styling on checkout. [image] About checkout styling Learn how Shopify Plus merchants can customize checkout's look and feel for a distinct visual identity.

Simplest way to inject CSS into Checkout Extensibility?

Extensions

Luke June 18, 2025, 7:11am 2

You cannot inject CSS into the checkout anymore.

Please refer to the below link for styling on checkout.

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Simplest way to inject CSS into Checkout Extensibility?

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