# Add custom CSS

Custom CSS can be applied to your Shopify theme using the built-in [custom CSS](https://help.shopify.com/en/manual/online-store/themes/theme-structure/extend/add-css) feature in the theme editor. It is the perfect option for minor visual tweaks that do not require editing theme source files — things like adjusting colors, spacing, typography, or button styles.

You can add custom CSS at two levels:

* **Section level** — open a section in the theme editor, scroll to the bottom of the settings panel, and expand **Custom CSS**. Changes apply only to that section.
* **Theme level** — navigate to **Theme settings > Custom CSS**. Changes apply across the entire storefront.

For commonly requested customizations, refer to the guides below.

{% content-ref url="/pages/2Bb5KZG6YFRlgUw2vruj" %}
[Popular custom CSS](/keystone/advanced-customizations/using-custom-css/popular-css-customizations.md)
{% endcontent-ref %}


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