typst-title.typ

#let title_block(
  title: none,
  subtitle: none,
  authors: none,
  date: none,
  abstract: none,
  title-size: none,
  subtitle-size: none,
  heading-family: none,
  heading-weight: none,
  heading-style: none,
  heading-color: none,
  heading-line-height: none
  ) = {
  if title != none {
    align(center)[#block(inset: 2em)[
      #set par(leading: heading-line-height)
      #if (heading-family != none or heading-weight != "bold" or heading-style != "normal"
           or heading-color != black or heading-decoration == "underline"
           or heading-background-color != none) {
        set text(font: heading-family, weight: heading-weight, style: heading-style, fill: heading-color)
        text(size: title-size)[#title]
        if subtitle != none {
          parbreak()
          text(size: subtitle-size)[#subtitle]
        }
      } else {
        text(weight: "bold", size: title-size)[#title]
        if subtitle != none {
          parbreak()
          text(weight: "bold", size: subtitle-size)[#subtitle]
        }
      }
    ]]
    }

  if authors != none {
    let count = authors.len()
    let ncols = calc.min(count, 3)
    grid(
      columns: (1fr,) * ncols,
      row-gutter: 1.5em,
      ..authors.map(author =>
          align(center)[
            #author.name \
            #author.affiliation \
            #author.email
          ]
      )
    )
  }

  if date != none {
    align(center)[#block(inset: 1em)[
      #date
    ]]
  }

  if abstract != none {
    block(inset: 2em)[
    #text(weight: "semibold")[#abstract-title] #h(1em) #abstract
    ]
  }
}