You can change the color scheme for your common pages to light or dark. The color scheme will apply to all your Home, Catalog, Custom, account, and checkout pages.
Steps to change your color scheme:
Click on Website
Customize your current theme
Click on Theme Customization at the bottom left of the editor
Toggle "Light" or "Dark" for your color scheme settings
Click Publish to set your new color scheme live.
When you choose the Light scheme, the pages affected by this scheme will display like the following:
When you choose the Dark scheme, the pages affected by this scheme will display like the following:
To view what each color scheme looks like on your site, select one of the schemes and view your storefront.