How can I disable page options when using HTML export?

Questions
1

I am trying to make a document that can export nicely to both HTML and PDF.

Notably, it has some configurations for things like page headers which I wish to exclude from the HTML export.

#set page(header: context {
  if counter(page).get().first() > 1 [
    #align(center, text[_My lovely essay_])
  ]
})
#set page(numbering: "— 1 —")

When I try to export to PDF, this fails due to page configuration not being allowed inside of containers.

error: page configuration is not allowed inside of containers
   ┌─ Essay.typ:7:1
   │
 7 │   #set page(header: context {
   │ ╭──^
 8 │ │   if counter(page).get().first() > 1 [
 9 │ │     #align(center, text[_My lovely essay_])
10 │ │   ]
11 │ │ })
   │ ╰──^

I have tried using the target() function to check for HTML export, but I haven’t managed to get it working.

I want to do something like:

#if target() == "paged" {
  // PDF-specific options
} else if target() == "html" {
  // HTML-specific options
}

How can I accomplish this?

2

set page is not supported in HTML.

// https://forum.typst.app/t/3701/2
#let target = dictionary(std).at("target", default: () => "paged")
#show: it => context {
  if target() == "html" { return it }
  set page(fill: blue)
  it
}