Hello Dear Luis!

Thanks for your question.

If you want to change colors for the custom areas in theme - please use Yellow Pencil plugin.
You may download it here: https://drive.google.com/open?id=1QVYd_ztJ_PJVg7uF7D9wa_8vSgdfwrFi
Also please visit this link in order to understand, how this plugin may change your website:
https://www.wpexplorer.com/customize-wordpress-theme-design/

Best Regards!