diff --git a/.gitmodules b/.gitmodules
index c88c38b7..c501295c 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -11,3 +11,6 @@
 [submodule "zsh/zplug"]
 	path = zsh/zplug
 	url = https://github.com/zplug/zplug
+[submodule "zsh/is_mosh"]
+	path = zsh/is_mosh
+	url = https://github.com/wookayin/is_mosh
diff --git a/install.py b/install.py
index 0dbe5865..8d0a77f7 100755
--- a/install.py
+++ b/install.py
@@ -47,6 +47,7 @@
     # Bins
     '~/.local/bin/dotfiles' : 'bin/dotfiles',
     '~/.local/bin/fasd' : 'zsh/fasd/fasd',
+    '~/.local/bin/is_mosh' : 'zsh/is_mosh/is_mosh',
     '~/.local/bin/imgcat' : 'bin/imgcat',
     '~/.local/bin/imgls' : 'bin/imgls',
     '~/.local/bin/fzf' : '~/.fzf/bin/fzf', # fzf is at $HOME/.fzf
diff --git a/tmux/tmux.conf b/tmux/tmux.conf
index c8bbd0ac..25132a19 100644
--- a/tmux/tmux.conf
+++ b/tmux/tmux.conf
@@ -150,7 +150,8 @@ set-window-option -g display-panes-time 1500
 set -g focus-events on
 
 # Color and Themes
-set-option -g default-terminal "screen-256color"
+set-option -g default-terminal "xterm-256color"
+set-option -ga terminal-overrides ",xterm-256color:Tc"     # True-color (24bit)
 
 # let pane/window numbers be 1-indexed
 set-option -g base-index 1
diff --git a/vim/vimrc b/vim/vimrc
index 8a8175e6..a4e58899 100644
--- a/vim/vimrc
+++ b/vim/vimrc
@@ -341,7 +341,11 @@ xnoremap <silent> <leader>ag y:Ag <C-R>"<CR>
 nmap <leader>cd :cd %:p:h<CR>
 
 " <leader>r : screen sucks, redraw everything
-nnoremap <leader>r :redraw!<CR>
+function! Redraw()
+  redraw!
+  call s:auto_termguicolors()   " re-detect true colors
+endfunction
+nnoremap <leader>r :call Redraw()<CR>
 
 " <leader>src : source ~/.vimrc
 nnoremap <leader>src :source ~/.vimrc<CR>
@@ -428,9 +432,41 @@ if &term =~ '256color'
     set t_ut=
 endif
 
+" 24-bit true color: neovim 0.1.5+ / vim 7.4.1799+
+" enable ONLY if TERM is set valid and it is NOT under mosh
+function! s:is_mosh()
+  let output = system("is_mosh -v")
+  if v:shell_error
+    return 0
+  endif
+  return !empty(l:output)
+endfunction
+
+function s:auto_termguicolors()
+  if !(has("termguicolors"))
+    return
+  endif
+
+  if (&term == 'xterm-256color' || &term == 'nvim') && !s:is_mosh()
+    set termguicolors
+  else
+    set notermguicolors
+  endif
+endfunction
+call s:auto_termguicolors()
+
+
 " apply base theme
 silent! colorscheme xoria256
 
+" airline theme: status line and tab line
+if &termguicolors
+  let g:airline_theme='deus'
+else
+  let g:airline_theme='bubblegum'
+endif
+
+
 " override more customized colors
 highlight StatusLine    ctermfg=LightGreen
 highlight ColorColumn   ctermbg=52 guibg=#5f0000
@@ -444,6 +480,18 @@ highlight Constant      ctermfg=204 guifg=#ff5f87
 highlight PreProc       ctermfg=219 guifg=#ffafff
 highlight SpecialKey    ctermfg=242 guifg=#666666
 
+" colors for gui/24bit mode {{
+" DiffAdd - inserted lines (dark green)
+highlight DiffAdd       guibg=#102a05 guifg=NONE
+" DiffDelete - deleted/filler lines (gray 246)
+highlight DiffDelete    guibg=#949494
+" DiffChange - changed lines (dark red)
+highlight DiffChange    guibg=#471515 guifg=NONE
+" DiffChange - changed 'text'(brighter red)
+highlight DiffText      guibg=#721b1b guifg=NONE
+" }}
+
+
 " no underline, current cursor line
 highlight CursorLine    cterm=none
 
@@ -489,8 +537,8 @@ autocmd BufWinLeave * call clearmatches()
 autocmd InsertLeave * silent! set nopaste
 
 " better popup menu colors (instead of dark black)
-highlight Pmenu ctermfg=black ctermbg=yellow
-highlight PmenuSel ctermfg=red ctermbg=white gui=bold
+highlight Pmenu ctermfg=black ctermbg=yellow guifg=black guibg=#ffec99
+highlight PmenuSel ctermfg=red ctermbg=white guifg=red guibg=white gui=bold
 
 " http://vim.wikia.com/wiki/Identify_the_syntax_highlighting_group_used_at_the_cursor
 function! ShowSyntaxGroup()
@@ -626,9 +674,9 @@ let g:EditorConfig_core_mode = 'python_external'
 
 " ---------------------------------------------------------------- }}}
 " Airline {{{
+" Note: for airline theme, see the 'appearance' section
 
 " use airline, with powerline-ish theme
-let g:airline_theme='bubblegum'
 let g:airline_powerline_fonts=1
 
 " enable tabline feature
diff --git a/zsh/is_mosh b/zsh/is_mosh
new file mode 160000
index 00000000..6cde1cf5
--- /dev/null
+++ b/zsh/is_mosh
@@ -0,0 +1 @@
+Subproject commit 6cde1cf5d4af45b2f9bcc4267d0beca0b2b61c17
diff --git a/zsh/zshrc b/zsh/zshrc
index 8a3ded6b..8c169992 100644
--- a/zsh/zshrc
+++ b/zsh/zshrc
@@ -86,12 +86,8 @@ zplug load #--verbose
 for config_file (${ZDOTDIR:-$HOME}/.zsh/zsh.d/*.zsh(N)) source $config_file
 
 # Terminal
-# screen-256color if inside tmux, xterm-256color otherwise
-if [[ -n "$TMUX" ]]; then
-  export TERM="screen-256color"
-else
-  export TERM="xterm-256color"
-fi
+# Use xterm-256color (for tmux, too)
+export TERM="xterm-256color"
 
 # iTerm integration (for OS X iTerm2)
 # @see https://iterm2.com/shell_integration.html