Relative size is the fastest signal of importance and the easiest one to overuse.
UI foundation · Visual design
Tag
scale
Entries tagged scale, drawn from across the library. Tags cut through the section structure, which is where most of the useful connections are.
3 entries across 1 section
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Level
3 entries
Consistent ratios between sizes make a layout feel considered, without needing any particular mystical ratio.
UI foundation · Visual design
A fixed set of sizes derived from one ratio, so type decisions become selections rather than inventions.
UI foundation · Typography