GP Tweaks is a plugin built and provided by DR7Media to enhance the free theme, GeneratePress. (I’m using it here on my own site, as well.)
GP Tweaks makes it easy to change the menu colors, menu sizes, header color, header text color.
Additional options include modifying the footer and the Back To Top button.
The default copyright text that comes default with the GeneratePress theme is removed. Preferred text including HTML can be added. Additionally, the background color, the text color and the link color of the text can be modified.
The Back To Top button color, and hover color can be modified according to your preference.[update: Version 1.0.3 has been released with a few more features and a couple of minor bug fixes]
Here is a screenshot of the menu and header modified by using GP Tweaks, version 1.0.3:
Here is a video overview of version 1.0.3:
Get the plugin from the wordpress repository at: https://wordpress.org/plugins/gp-tweaks/.