# Custom CSS

Custom CSS can be added to your entire theme that affects all pages in your online store except the Checkout page.

1. From your Shopify admin, go to **Online Store** **->** **Themes**.
2. Find the theme that you want to edit, and then click **Customize**.
3. Click **Theme Settings -> Custom CSS.**

{% hint style="info" %}
See Shopify [Adding custom CSS to your theme](https://help.shopify.com/en/manual/online-store/themes/theme-structure/extend/add-css) here for more details about using this setting on your store.
{% endhint %}


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