bug report: not completely dark/black.

[kgfly]

On Windows, this is my mini .vimrc

let vimplug_path = expand('~/.vim/autoload/plug.vim')
let plugged_path = expand('~/.vim/plugged')

if empty(glob(vimplug_path))
    silent execute '!curl -fLo ' . vimplug_path . ' --create-dirs ' .
        \ 'https://raw.githubusercontent.com/junegunn/vim-plug/master/plug.vim'
    if v:shell_error
        echom "Error downloading vim-plug. Please install it manually."
    else
        augroup VimPlugInit
            autocmd!
            autocmd VimEnter * PlugInstall --sync | source $MYVIMRC
        augroup END
    endif
endif

if stridx(&runtimepath, expand('~/.vim/autoload')) == -1
    set runtimepath+=~/.vim/autoload
endif

if filereadable(vimplug_path)
    execute 'source ' . fnameescape(vimplug_path)
endif

set nocompatible
filetype off

if exists('*plug#begin')
    call plug#begin(plugged_path)
    Plug 'tomasiser/vim-code-dark'
    call plug#end()
endif

filetype plugin indent on

if exists('*plug#begin') && len(filter(values(g:plugs), '!isdirectory(v:val.dir)'))
    augroup PlugInstall
        autocmd!
        autocmd VimEnter * PlugInstall --sync | source $MYVIMRC
    augroup END
endif

colorscheme codedark

As you can see, it's not completed dark/black. It's black with gray color, comparing to the windows terminal windows on the left side.

How to set it completely dark? (which vscode has)