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Footnote Margin Note
Hover a footnote marker and it fills into a circle, the cited phrase underlines, and a hairline leader draws from the marker out to the margin, where a small serif note slides in.
Also known as: css sidenote hover, tufte margin note, footnote leader line, marginalia tooltip css.
Early printers left a blank square at the head of each chapter for the rubricator1 to paint the initial by hand, in red and blue.
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Customizing this snippet
- Color: set
--hfx-coloron the element or a parent. Currently previewing#3b82f6. - Base size: set
--hfx-size. Every other dimension is inem, so the whole thing scales together. Currently previewing16px. - Speed: change the duration on the
transitionoranimationshorthand. Staggered delays are relative, so they keep their rhythm. - Reduced motion: the rule at the end of the CSS turns the motion off for people who asked their OS for less of it. Keep it.