I have edited
dokuwiki\lib\tpl\my_beautiful_templet\style.ini to show dokuwiki in custom font as follows.
I have added
font-family = "mybeautifulfont; src: url(_/path/to/my/beautiful/font.ttf)"
under the lines
;------ guaranteed dokuwiki color placeholders that every plugin can use
; main text and background colors
in style.ini
I hope this trick may work with all the templets using style.ini file.
Anybody please, confirm this trick and post a reply.