#let poem(content) = {
  set par(first-line-indent: 0em)

  align(center, block[
    #set align(left)
    #set block(breakable: false)
    #content
  ])
}

#poem[
  #block[
    “Tweedledum and Tweedledee \
    #h(1em)Agreed to have a battle; \
    For Tweedledum said Tweedledee \
    #h(1em)Had spoiled his nice new rattle.
  ]

  #block[
    Just then flew down a monstrous crow, \
    #h(1em)As black as a tar-barrel; \
    Which frightened both the heroes so, \
    #h(1em)They quite forgot their quarrel.”
  ]
]