I have a trouble setting up a variable of a type Dictionary from the command line.
From what I see in the docs, there's only one such variable, namely the margin for typst.

There's no problem setting it with the defaults YAML, but I'm not sure if pandoc currently can parse a dictionary from the command line.
The issue is exacerbated by a total lack of any error feedback on incorrectly formatted options from the CLI.

The following syntaxes should be equal:

• CLI: -V margin={left:1cm, right:1cm, bottom:1cm, top:1cm, x:0cm, y:0cm}

• defaults.yaml:

  variables:
    margin:
      left: 1cm
      right: 1cm
      bottom: 1cm
      top: 1cm
      x: 0cm
      y: 0cm

Tested on latest release (3.5).