The stylesheet relativize.css, which is provided for different Markdeep versions, "relativizes" sizes: It overrides sizes/lengths defined in terms of px, pt etc. in the stylesheets that are automatically applied by Markdeep with lenghts defined in terms of rem. This enables scaling the entire document simply by adjusting the <html> element's font size – exactly what's required to enable
- fullscreen presentations via markdeep-slides,
- adjustable base font sizes in markdeep-thesis,
- and more!
The conversion rule is simple: ⟨N⟩px ⟼ calc(⟨N⟩rem / var(--rf)), where --rf is the base font size the original px measurements are assumed to be relative to. In fact, --rf is the browser default, 16px. (Note that I would've preferred to define --rf: calc(1rem / 16px) and then use it like calc(⟨N⟩px * var(--rf)), but calc disappointingly, yet understandably, can't deal with "rem per pixel" units in current browsers.)
When applied to a standard Markdeep document (i.e. loaded before Markdeep), this stylesheet is designed not to yield any visual changes (unless you change the root font size from its 16px default, that is).