add background color setting when opened window

[mikinovation]

• fix the background color when opened window

[mikinovation]

I use WSL2.
Please try this command :hi NormalFloat ctermfg=LightGrey or add vim setting vim.api.nvim_set_hl(0, 'NormalFloat', {fg = LightGrey}) so that it's temporaly fixed.

I'll add feature for setting background color