Dokuwiki has new template placed in `/lib/tpl/arkhalia_wiki_tpl`. There is several interesting places. At first there is a logo placed in `images/logo.png` which is replaced by “Arkhalia” logo. Then in `css/basic.less` can be changed the overall font size used in wiki:

body {
    font: normal 92%/1.4 "Inter var", "ui-sans-serif", "system-ui";;
    /* default font size: 100% => 16px; 93.75% => 15px; 87.5% => 14px; 81.25% => 13px; 75% => 12px */
    -webkit-text-size-adjust: 100%;
}

Another interesting place in template is in the `main.php` where the original procedure (not a function, its a procedure):

    <?php tpl_content() ?>

Has been replaced by the logic of the linter:

if (!str_contains($buffer, '<h1')) {
  echo '👮‍️ Arkhalia Wiki guard: Please add h1 title into the Article. Reason: It doesn\'t look good to not have h1 caption in the Article.';
}
                    } 

The colors can still be changed in Admin panel, or can be placed at the botton of the `style.ini` file. You can grab a color setting from different template, like adoradark:

[replacements]
;These overwrites have been generated from the Template styling Admin interface
;Any values in this section will be overwritten by that tool again
__text__ = "#eeeeee"
__background__ = "#222222"
__text_alt__ = "#dddddd"
__background_alt__ = "#444444"
__text_neu__ = "#cccccc"
__background_neu__ = "#333333"
__border__ = "#ff9900"
__highlight__ = "#aaaa66"
__link__ = "#ff9900"
__background_site__ = "#000000"
__existing__ = "#ffff88"
__missing__ = "#ff4433"
__site_width__ = "75em"
__sidebar_width__ = "16em"
__tablet_width__ = "800px"
__phone_width__ = "480px"

And place it at the bottom of the file.

You can instal different template and try it, the Arkhalia tpls will be persistent. However it is very likely that you just want different color settings. If you want better desing overall, then I'm skeptical it can be achieved with Dokuwiki templates.