Combinations and limits

What is supported, what is not

Combination	Status
content cols-3 cards	supported
content gallery cols-3 bg	supported
content timeline cols-4 cards	supported
content image-text-80 fit with-title	supported
content gallery-bento cols-3	avoid fixed bento geometry
content image-text-80 timeline	incompatible two compositions
title cols-2	not supported
color-1 color-2	ambiguous two palettes
small medium	ambiguous two sizes
fit bg	ambiguous two fit modes

The browser will not warn you

An invalid combination is not rejected by the browser: some rules win through specificity or declaration order, and the result can be misleading. An unknown class may have no effect at all. Do not invent suffixes like image-text-73 assuming the number will be understood.

This is precisely the role of the VS Code extension: it knows the catalog and flags unknown classes, ambiguous combinations and incorrect structures. See Writing with assistance.

Overflowing content

Content that overflows the slide may be hidden (overflow: hidden): you will not necessarily see it in the preview. What to do, in order:

1. medium or small;
2. shorten the content;
3. create an additional slide.

The theme alone measures nothing and does not split pages. The extension, on the other hand, measures the rendering in Chromium and flags overflows. See Overflows and callouts.

Other limits to know

• Image/text layouts expect one image and one text group.
• The bento expects six images and does not compute arbitrary mosaics.
• A caption applies to the whole slide, not to each card.
• Opaque backgrounds limit perfect independence between palette and styling (see overlaid tints).
• Modern CSS functions such as :has() and color-mix() require a recent rendering engine.
• Changing the font or theme can change line breaks.
• A theme must implement this contract to accept these classes: the language is not native to ordinary Marp themes. See Creating a compatible theme.