Halcyon Theme for Neovim

A minimal, dark blue theme for Neovim and lightline.vim, ported from halcyon-vscode. Due to limitations in vim's syntax highlighting (even with additional plugins), it's impossible to replicate @bchiang7's original theme. This is mostly meant to be used under iTerm2 with the halcyon-iterm theme, but without the iTerm2 theme it's still a decent Neovim theme by itself if you have a terminal with 256 colour support. Note that this theme does not support Vim.

Language Support

Languages I've tweaked this theme with: C, JavaScript, TypeScript, Golang, Python, Common Lisp, HTML, CSS, Scss, Markdown, YAML and Bash. In particular, JavaScript support requires Plug 'pangloss/vim-javascript', Python support requires Plug 'vim-python/python-syntax', HTML and Markdown support requires Plug 'plasticboy/vim-markdown' and Golang support requires Plug 'fatih/vim-go'. If you find a better syntax plugin for a particular language, feel free to ping me or send a PR.

Installation

Using vim-plug. It's very important that you have set termguicolors in the init file or the colours won't render properly.

Plug 'kwsp/halcyon-neovim'
colorscheme halcyon
set termguicolors

This theme requires a 256 colour or true colour terminal.

Usage

In addition to the vim theme, a minimal lightline.vim theme is provided. Add the following line to your .vimrc:

let g:lightline = {
      \ 'colorscheme': 'halcyon',
      \ }

If you are using Tmux, you may need to add the following line to your Tmux config file:

set -g default-terminal "screen-256color"

This theme supports transparent terminals out of the box (most of the background colours in this theme are empty) so it may not work well with a non-transparent terminal.

If you are using a terminal without opacity, setting the background colour to #1d2433 can make a big difference.

References

halcyon-vscode

Neovim Documentation