customizer — support — wordpress.com

You can use the Customizer to preview and modify many of your appearance settings, from your Custom Header Image to widgets and more..
You can access the Customizer from any page or post on your site just go to the in the corner of the screen and click Customize...
To access the Customizer from the dashboard, you can go to My Sites → Themes → Customize  . customizer dashboard.
Once inside the Customizer,  you can preview what your site content would look like in theme click on Change next to your theme, and you'll see selection of themes to preview . By selecting any of the You can preview changes in the Customizer and making tweaks to the current settings.
Note  but do not see them saving on the live site, check to make sure your action is not set to Save Draft or Schedule. It must be set to Publish to appear on the live site...
which gives unrestricted access to Custom Colors, Custom Fonts, and CSS Editor.
Colors & Backgrounds  — change your palette with few clicks..
Fonts  — select from list of custom fonts for headings and body text..
be sure to select Publish if you wish to keep your new settings, or close the Customizer to discard all changes..
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