Support for Dark Mode

[beevelop]

The widget works and looks great on primarily bright backgrounds. With a dark background the contrast is sometimes a bit difficult.

Two ideas that might be useful:

• Making the color theme of all colors customizable.
• Providing predefined colorsets for e.g. dark / bright colors.

[sgehrman]

yeah, or have a color override.

[chongbo2013]

can support edit json ,tku

[mayankkushal]

There is no activity here, this package seems to be forgotten, I have updated the package under a new name flutter_json_viewer, if anyone still needs to use it.