DonnyBahama I looked at the wrap plugin but couldn't wrap my head around how it works.
As it states on the plugin page, the main purpose of the wrap plugin is essentially, that you can enwrap some content (text) with start/end tags of an HTML element, like so: DokuWiki markup
<WRAP>text</WRAP> is translated to HTML as
<div>text</div>. In other words, you embed this text into a div element, which did not exist before.
Now, the whole point in doing so, is, that HTML elements can be styled by CSS. Therefore, one way or another, behind the scenes, you need to attach an HTML element type and your custom class name, in order to address this text with your custom CSS style. This is exactly, what the wrap plugin is there for. Besides installing other special plugins, there is no other way for you as a user to add any custom styles (other than standard DokuWiki markup) to some text in your wiki. It's as simple as that! That's why the wrap plugin is also referred to as the one plugin to rule them all.
(To be precise, there is one exception, if you want to change the CSS style for this HTML element in general, you don't need a custom class name, but then all other occurrences of this HTML element in your wiki could also be effected. And you would still need the wrap plugin to attach the HTML element type to your string of text. However, I would not recommend this, since the output of other plugins could be messed up and all possible effects are not always predictable.)