[Jellby]

Novels often have fragments of poetry or songs interspersed in them. As we all know, poetry has some formatting requirements (hard line breaks) and some display customs (centered or indented block).

I use code like the following when I have to format poetry fragments in a text. I use individual <p></p> for each line instead of just <br/> because I want to use the effect of the negative parindent: when a line is too long to fit the screen, it is "soft-broken" and the second portion is indented farther to the right (actually, I'd like it to be left-aligned and preceded by "[", but I don't think that's possible)

xhtml:

<div class="poetry">
<p>Sur une gamme chromatique,</p>
<p class="indented">Le sein de perles ruisselant,</p>
<p>La Vénus de l’Adriatique</p>
<p class="indented">Sort de l’eau son corps rose et blanc.</p>

<p class="first">Les dômes, sur l’azur des ondes</p>
<p class="indented">Suivant la phrase au pur contour,</p>
<p>S’enflent comme des gorges rondes</p>
<p class="indented">Que soulève un soupir d’amour.</p>

<p class="first">L’esquif aborde et me dépose,</p>
<p class="indented">Jetant son amarre au pilier,</p>
<p>Devant une façade rose,</p>
<p class="indented">Sur le marbre d’un escalier.</p>
</div>

css:

div.poetry {
  margin: 1em 0 1em 2em;
}
div.poetry p {
  margin: 0;
  padding-left: 3em;
  text-indent: -3em;
  text-align: left;
}
div.poetry p.indented {
  margin-left: 2em;
}
div.poetry p.first {
  margin-top: 1em;
}

So, use class="first" when a new stanza begins and class="indented" for indented lines.

For pieces with more complex indent pattern or for mainly poetry works I'd probably do something different, like a <div></div> for each stanza (which could include "page-break-inside: avoid" in the css).