You spend so much time looking at Grasshopper, might as well make it look the way you like!
Palette is a single component which lets you customize Grasshopper's GUI and toggle between your Custom GUI and Grasshopper's standard GUI. This component contains all the available GUI options for Grasshopper. These options include canvas colors, component colors, wire colors, and more. Palette changes are reversible by switching the mode to false. Once you set your custome GUI you don't need Palette on canvas anymore. Palette GUI changes stay even after closing Rhino and Grasshopper until you turn it back to standard. Saving a file with a Custom GUI and opening it on another computer will not make the other computers Grasshopper GUI change, so don't worry about sending files to others. If total customization is not your thing, check out the plug-in Moonlight (food4rhino.com/app/moonlight) for a nice clean Dark Mode. Palette is written in C# as a .gha file. Palette will install at the bottom of Grasshopper's Params > Util tab.
If you want a transparent canvas that you can see through to Rhino, check out Wormhole by Daniel Abalde: https://www.grasshopper3d.com/profiles/blogs/transparent-canvas-wormhole-to-rhino-viewport
Instagrams: @ekim.royrp & @designmorphine
WARNING: If you already have a customized GUI it will not come back after Palette. Palette switches between Custom GUI and Grasshopper's standard GUI. If you wish to save your custom GUI settings before using Palette, in Grasshopper go to File > Special Folders > Settings Folder - and make a copy of the file "grasshopper_gui.xml". When you want your customized GUI back just replace the "grasshopper_gui.xml" with your copy. When you replace it, it must be named "grasshopper_gui.xml". The "grasshopper_gui.xml" is always updated with GUI changes so you must make the copy before using Palette or else Palette will overwrite it.
How to intall Grasshopper plug-ins: www.youtube.com/watch?v=TB5wkh79Pv4
*If you have both Rhino 5 and Rhino 6 then you only need to install Palette in Grasshopper for Rhino 5, Rhino 6 Grasshopper will pick it up automatically.
If you are interested in developing your own GUI component, all the needed methods can be found in the GH_Skin class: https://developer.rhino3d.com/wip/api/grasshopper/html/T_Grasshopper_GUI_Canvas_GH_Skin.htm
August 29, 2018 - Palette V1.0
Grasshopper for Rhino 6 for Win