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

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

#poem[
  #block[
    ‘Up above the world you fly, \
    Like a tea-tray in the sky. \
    #h(2em)Twinkle, twinkle---’”
  ]
]