Material Adapta Nokto Theme
A theme that uses similar colors to the adapta-nokto gtk theme in Chrome, modified for greater contrast with the active tab.
Not affiliated with the actual adapta gtk theme.
Github
This theme is fully open-source under the Apache License. Check out the source code on Github.
It was forked from Fiddle-N's material-incognito-dark-theme.
Colors are based on the adapta-nokto theme, also available on Github