make bat(1) use terminal colors

en

@@ -1,6 +1,6 @@
 #!/bin/sh -e
 
-# Copyright (c) 2023 Emma Tebibyte 
+# Copyright (c) 2023 Emma Tebibyte <emma@tebibyte.media>
 # SPDX-License-Identifier: FSFAP
 #
 # Copying and distribution of this file, with or without modification, are
@@ -45,6 +45,8 @@ while test -n "$1"; do
 	# use bat for syntax highlighting if it’s available, but remove the frills
 	if command -v bat >/dev/null
 	then
+		# make bat use terminal theme
+		BAT_THEME=ansi; export BAT_THEME
 		# there has to be a temp file for writing the highlighted text to
 		syntax_h() {
 			printf "%s\n" "$1" >"$temp_highlight"