setting background doesn't work

[yukunfeng]

Hello, thanks for this nice color scheme. Now I'm using iterm2 and already used NeoDark.itermcolors. The colors in my terminal are nice. But in vim, the background color is always like Vim (256 color), third picture in README.md. And I cannot change this color to default dark color though I tried some combinations of given commands in README.md.

[yukunfeng]

I've got dark background color. I tried some codes to support true color in my vimrc. The codes are from here:

if (empty($TMUX))                                                                                     
  if (has("nvim"))                                                                                    
  let $NVIM_TUI_ENABLE_TRUE_COLOR=1                                                                   
  endif                                                                                               
  if (has("termguicolors"))                                                                           
    set termguicolors                                                                                 
  endif                                                                                               
endif