SpellBad highlight not working correctly.

[isaif]

SpellBad highlighting is just showing the underline and no change in colour.

I have seen the code in your plugin where it sets the colour to error. So I think the background color should change, but why doesn't it works for me?

SpellBad = { sp = c.error, style = "undercurl" },

Theme config:

vim.g.gruvbox_flat_style = "dark"
vim.o.cursorline = true
vim.o.showmode = false

vim.cmd('colorscheme gruvbox-flat')

local success, lualine = pcall(require,'lualine')

if success then
  lualine.setup{
    options = {theme = 'gruvbox-flat'},
  }
else
  error('lualine is not installed')
end

Here is the output for :hi

I am using linux with neovim in konsole terminal:

NVIM v0.7.0-dev+761-g0d7a97224
Build type: Release
LuaJIT 2.1.0-beta3
Compiled by root@linux

Features: +acl +iconv +tui
See ":help feature-compile"

   system vimrc file: "$VIM/sysinit.vim"
  fall-back for $VIM: "/usr/local/share/nvim"

I have treesitter enabled and vim regex highlight disabled.

require'nvim-treesitter.configs'.setup {
  ensure_installed = "maintained",
  highlight = {
    enable = true,
    additional_vim_regex_highlighting = false,
  },
}