I just updated the Delphi IDE Theme Editor adding support for RAD Studio 10 Seattle.
Remember which starting with Delphi XE8, DITE allows you edit the values (color and font) of the IDE modern theme. To use it just press the button “Additional Settings” and set values for the Main ToolBar and the IDE Font, finally press the button “Apply”. Also you can restore the default settings pressing the button “Restore”.
You can download the DITE from here.
The Road to Delphi 
September 1, 2015 at 1:31 pm
congratulations on the excellent work, was waiting.
September 8, 2015 at 4:01 pm
Having an issue with it not detecting Delphi. I’m on Windows 10 with Delphi 10 Seattle installed but when I load up DITE, I get the error message “You don’t have a Object Pascal IDE installed (1)”.
September 8, 2015 at 4:08 pm
Please use the issue page of the project https://github.com/RRUZ/delphi-ide-theme-editor/issues to report this.