You'll be happy to know, it is supported very easily :)
For those scenarios you can use the conditional statements. They work with predefined attributes and custom ones as well:
http://asciidoctor.org/docs/user-manual/#ifdef-directive.
For example, see how icons get a special treatment when an attribute set by GitHub is defined (env-github) here
https://raw.githubusercontent.com/asciidoctor/asciidoctor/master/README.adocIf you use IntelliJ, it defines the attribute `env-idea` to customize the images path for a specific document.
ifdef::env-github[]
:status:
:outfilesuffix: .adoc
:caution-caption: :fire:
:important-caption: :exclamation:
:note-caption: :paperclip:
:tip-caption: :bulb:
:warning-caption: :warning:
endif::[]
Also, you may be interested in checking how to unset attributes with the `!` symbol:
http://asciidoctor.org/docs/user-manual/#using-attributes-set-assign-and-reference.