How to do additional colors customization for theme?

First of all, you may change the background, color, and overlay color of sections in Unyson Page Builder. 

The manual about how to use Unyson Page Builder you may download here: https://drive.google.com/file/d/1GmC2CFXsx_vuRufzgEG0NISgFPTVsG22/view 

It will help you to perform many changes with content and colors on your current website.

If you want to change colors for the custom areas in the theme - please use the Yellow Pencil plugin. 

You may download it here: https://drive.google.com/open?id=1QVYd_ztJ_PJVg7uF7D9wa_8vSgdfwrFi

Also please visit this link to understand, how this plugin may change your website: 

https://www.wpexplorer.com/customize-wordpress-theme-design/

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