Create or find colour theme

[fsasm]

New colour theme should be dark with higher contrast that is suitable for older LCD screens with faded colour and is also readable in environments with sunlight.

[fsasm]

Current theme is ´navarasu/onedark.nvim´ in the darker variant with custom grey for better visibility of comments.
Candidates are:

• Monekai from NvChad which is based on Monokai
• Yoru from NvChad
• NighOwl

Because I will definitely modify the colour schemes, some plugin for custom colour schemes would be helpful.