Update terminal colours

alacritty.yml

@@ -3,14 +3,14 @@
 # Any items in the `env` entry below will be added as
 # environment variables. Some entries may override variables
 # set by alacritty itself.
-#env:
+env:
   # TERM variable
   #
   # This value is used to set the `$TERM` environment variable for
   # each instance of Alacritty. If it is not present, alacritty will
   # check the local terminfo database and use `alacritty` if it is
   # available, otherwise `xterm-256color` is used.
-  #TERM: xterm-256color
+  TERM: xterm-256color
 
 #window:
   # Window dimensions (changes require restart)

tmux.conf

@@ -1,8 +1,9 @@
 # https://gist.github.com/spicycode/1229612
 
 set -g default-terminal "screen-256color"
-set -g base-index 1
+set -ga terminal-overrides ',*256col*:Tc'
 
+set -g base-index 1
 set-window-option -g automatic-rename off
 set-window-option -g allow-rename off
 set-option -g set-titles on

vimrc

@@ -27,8 +27,6 @@ set expandtab
 set splitbelow
 set splitright
 set encoding=utf-8
-set t_Co=256
-set termguicolors
 set hidden
 set history=1000
 set nowrap
@@ -71,6 +69,14 @@ set pumheight=200
 set completeopt=menu,menuone,popup,noselect
 set completepopup=width:300,height:50,align:item,border:off
 
+" Enable 24-bit colours.
+" https://github.com/alacritty/alacritty/issues/109#issuecomment-440353106
+if exists('+termguicolors')
+  let &t_8f="\<Esc>[38;2;%lu;%lu;%lum"
+  let &t_8b="\<Esc>[48;2;%lu;%lu;%lum"
+  set termguicolors
+endif
+
 " Colour scheme:
 colorscheme nord