The rules

  1. Directives

4. Directives

Directives are HTML comments on a line of their own:

markdown
<!-- name: value -->
<!-- name -->

They stay invisible on GitHub and in other markdown viewers. A comment whose first word is followed by anything other than : or --> is an ordinary comment (<!-- note to self -->, <!-- TODO -->); a lowercase single word that is not a directive (<!-- wobble -->) is an error.

Directive Scope Section
layout: center slide Layouts
column body Layouts
transition: zoom slide Transitions
background: assets/city.jpg opacity=0.4 slide Backgrounds
footer: off slide overrides the deck footer on this slide (off hides it, e.g. the title)
labs: [Create a Cluster](https://…), [Scale out](https://…) slide turns the slide into a lab slide: a centred beaker icon, the labs-label heading, and a button per lab (opens in a new tab). A bare URL works too and shows a default label.
class: dense dark-code slide adds classes to the slide for your CSS
eyebrow: Order #4711 · the promise slide a small context label above the slide heading (.si-kicker); it is not part of the slide title, so find, the overview and the teleprompter show the heading alone. On a section slide it replaces the "Part N" kicker.
image: width=40% align=right next image Images
steps, step, steps: a b, step: a next block Build steps
svg: assets/canvas.svg state words body SVG canvases
include: other.md deck Includes

Body directives (column, image, step, steps, svg) work on the top-level blocks of a slide, not inside lists or quotes.